PRINT POST APPROVED PP 100003880
Volume 41 no 5 AUGUST 2014
Journal of the australian Water association
rrP $18.95
PUSHING WATER UPHILL
could this simple solution be an answer to our renewable energy issues? see page 30. Plus > Biosolids & source Management > Managed aquifer recharge > Wastewater treatment > smart systems
A new teAm tHAt wILL deLIver tHe worLd’s best ductILe Iron pIpeLIne system
Pentair Water Solutions has formed an alliance with Saint-Gobain PAM to provide ductile iron pipeline systems with shorter lead times, new products and cutting edge technical expertise for the water industry throughout Australasia. This new alliance will provide over 200 years of experience in cast iron pipe manufacture, supply, construction, operation and maintenance. The trusted brands TYTONXCEL and TYTONXTREME will continue, still featuring the unrivalled TYTON® rubber ring joint. Pentair’s commitment to exceeding customer expectations in delivery are now matched with PAM’s dedication to quality through product excellence. PENTAIR.COM/WATERSOLUTIONS
PAWJ1306
1
Contents regular features From the AWA President
The Value Of Selection And Maintenance Of The Aim Graham Dooley
2
From the AWA Chief Executive
contents
A New Focus And Structure For AWA Jonathan McKeown
4
My Point of View
water journal ISSN 0310-0367
MANAGING EDITOR – Anne Lawton Tel: 02 9467 8434 Email: alawton@awa.asn.au TECHNICAL EDITOR – Chris Davis Email: cdavis@awa.asn.au
Will We Just Watch As The Water-Science Gap Widens? Chris Davis
6
Crosscurrent
8 12
Industry News Young Water Professionals The Irresistible Force Paradox Justin Simonis
22
AWA News
23
Water Business
New Products And Services
88
Advertisers Index
92
CREATIVE DIRECTOR – Mike Wallace Email: mwallace@awa.asn.au SALES & ADVERTISING MANAGER – Kirsty Muir Tel: 02 9467 8408 (Mob) 0412 077 964 Email: kmuir@awa.asn.au CHIEF EXECUTIVE OFFICER – Jonathan McKeown EXECUTIVE ASSISTANT – Despina Hasapis Email: dhasapis@awa.asn.au EDITORIAL BOARD Frank R Bishop (Chair); Dr Bruce Anderson, Planreal Australasia; Dr Terry Anderson, Consultant SEWL; Dr Andrew Bath, Water Corporation; Michael Chapman, GHD; Wilf Finn, Norton Rose Fulbright; Robert Ford, Central Highlands Water (rtd); Ted Gardner (rtd); Antony Gibson, Orica Watercare; Dr Lionel Ho, AWQC, SA Water; Dr Robbert van Oorschot, GHD; John Poon, CH2M Hill; David Power, BECA Consultants; Dr Ashok Sharma, CSIRO. PUBLISH DATES Water Journal is published eight times per year: February, April, May, June, August, September, November and December. Please email journal@awa.asn.au for a copy of our 2014 Editorial Calendar.
30
• Technical Papers & Technical Features: Chris Davis, Technical Editor, email: cdavis@awa.asn.au AND journal@awa.asn.au
Tumut pond reservoir in the Upper Tooma river.
interview
Let’s Talk About Water
An Interview With MWH Global’s David Smith
27
volume 41 no 5
feature articles 30
Up For A Great Cause
The Queensland YWPs’ Presentation At A Youth Detention Centre Abraham Negaresh
32
opinion
Trade Waste Regulation And Pricing For Utilities Neil Christie
34
conference report 2014 Biosolids And Source Management Conference A rundown of this year’s event Diane Wiesner
38
technical papers
42
cover Penstocks at the Tumut 3 Power Station at Talbingo in the Snowy Mountains, New South Wales.
Technical Paper Submission Guidelines Technical Papers should be 3,000–4,000 words long and accompanied by relevant graphics, tables and images. For more detailed submission guidelines please email: journal@awa.asn.au • General Feature Articles, Industry News, Opinion Pieces & Media Releases: Anne Lawton, Managing Editor, email: journal@awa.asn.au
Pushing Water Uphill
Could This Method Solve Our Renewable Energy Issues? Andrew Blakers & Roger Fulton
EDITORIAL SUBMISSIONS Acceptance of editorial submissions is at the discretion of the Editors and Editorial Board.
General Feature Submission Guidelines General Features should be 1,500–2,000 words and accompanied by relevant graphics, tables and images. For more details please email: journal@awa.asn.au • Water Business & Product News: Kirsty Muir, Sales & Advertising Manager, email: KMuir@awa.asn.au ADVERTISING Advertisements are included as an information service to readers and are reviewed before publication to ensure relevance to the water sector and the objectives of AWA. PUBLISHER Australian Water Association (AWA) Publishing, Level 6, 655 Pacific Hwy, PO Box 222, St Leonards NSW 1590; Tel: +61 2 9436 0055 or 1300 361 426, Fax: +61 2 9436 0155, Email: journal@awa.asn.au, Web: www.awa.asn.au COPYRIGHT Water Journal is subject to copyright and may not be reproduced in any format without the written permission of AWA. Email: journal@awa.asn.au DISCLAIMER The Australian Water Association assumes no responsibility for opinions or statements of fact expressed by contributors or advertisers.
AUGUST 2014 water
2
From the President
THE VALUE OF SELEcTiOn And MAinTEnAncE OF THE AiM Graham Dooley – AWA President
One of the excellent management principles I came across early in my career is from the Australian Army’s principles of land warfare: Selection and Maintenance of the Aim. I have found that being clear about what the target is, and then maintaining a focus on that target and applying resources to achieve it, is a most helpful principle to revisit from time to time in life, both personally and corporately. Some long-term AWA members may read Jonathan’s column in this edition and roll their eyes and say, “But that is what we have been doing for 52 years now – this is not new”. And it isn’t. But it is beneficial to go back to basics and renew our commitment, initiated 52 years ago by our founding fathers: that this is our “Aim” and this is what we are focusing on and directing our Association’s effort towards. In a nutshell we are focused on three things: 1.
Being the clearing house and crossroad for all the information that washes across our Australian water sector;
2.
Enhancing and uplifting the skills, knowledge and careers of our individual members – as well as their enjoyment of the industry;
3.
Creating the best possible avenues and opportunities for our corporate members to advance their enterprises, whatever those may be. The AWA Board is committed to ‘getting smart’
about how we do this. For example:
water august 2014
• I can download the soundtrack of an old movie or song from decades ago exceedingly quickly – in comparison, it is much more difficult to access the valuable information contained in a paper presented last month or last year at a Branch or national event. We need to modernise all that. • Individuals who have worked in the water industry and those that are coming through the water industry deserve to have their skills and expertise formally recognised and kept up-to-date by a specially tailored system of professional accreditation. This professional accreditation for the water industry is something that AWA, as the national water industry association, should be able to facilitate for its members. How AWA coordinates our many professional development training options under such an accreditation system is the challenge ahead for the organisation and our members. • Our corporate members have the best water know-how in the world. Look at our drought response, our asset management skills and our river management capabilities. They are second to none! We need to help our corporate members enhance their activities and extend their good work across our region and further afield. There is much to do and we have selected the ‘three pillars’ Jonathan speaks of, not as anything particularly different from our last 52 years, but as a reaffirmation of our aim, and a commitment to focusing our energy and attention on these three deliverables for our members.
SS6 Potable Water Pump Station, Burleigh Heads, Queensland
“Knowledge that lives beyond the project” Comdain is a leading national infrastructure design, construction and maintenance services business specialising in the Water, Irrigation and Gas sectors. We deliver our construction and maintenance services safely with professional excellence and best practice in alignment with our core values. Our focus is to deliver innovation that is sustainable, where practical, ensuring the future of water resources is secured for all users. Our water capabilities include:
Current & Recent projects include:
Program Planning & Management and Consultation.
South East Water (VIC) Pipes & Structures Program 2013-2018: Panel member (through LD&C joint venture) for the design and construct of South East Water’s Capital Works Program.
Design - Concept, detailed and delivery methodology. Construction - Pipelines, Pump Stations, Structures, Storage and Treatment Plants. Maintenance - Civil, mechanical and electrical. Control & Monitor - Metering, SCADA and telemetry.
Intelligent Doers, Dependable Delivery comdaininfrastructure.com.au
Sydney Water Corporation (NSW) Network & Facility Renewals Program: Delivery Contractor panel member providing design and construction services. Queensland Urban Utilities (QLD) Panel member for the provision of Design and/or Construction of Water and Sewerage Reticulation Systems. Goulburn-Murray Water (VIC) Goulburn Murray Water Connections Project: Managing Contractor role through the TransCom Connect JV responsible for the planning, design, scheduling and procurement of services associated with the $2b irrigation modernisation program.
4
From the CeO
A nEw FOcUS And STrUcTUrE FOr AwA Jonathan McKeown – AWA Chief Executive
It’s a time of change in the water industry. As a result, AWA needs to evolve its service and product offering and methods of delivery to maintain maximum relevance to our members. We also need to adapt to changes in the markets, environment and regulatory regimes within which our members operate in order both to better serve them and meet our overall objectives for sustainable water management.
In summary, we will promote a clear membership proposition, diversify and stabilise our revenues, and increase member engagement. To achieve these objectives we need to marshal our limited resources to build the professional capacity of, and create new opportunities for, our members, who can then drive Australia’s prosperity with reliable and accurate water information, expertise and collaboration.
As a result of extensive interactions and careful deliberation on the opportunities and challenges faced by the Association the AWA Board has determined a new business focus with a new staff structure that is aligned to delivering results. At the core of our success will remain our ability to nurture and recognise the many passionate individuals who contribute to the Australian water industry.
The new business strategy is built on three core pillars of activity, as outlined below:
Just as the Australian water sector is evolving, with the introduction of new technologies the way in which individuals manage their career development and professional expertise is also radically changing. Underpinning these changes are the technological advances in how we communicate for knowledge, business and community involvement. Australia’s economic development and international business potential are directly linked to industries that are dependent on sustainable water management. In response, AWA needs to broaden its reach across the different sectors to articulate the importance of sustainable water management and share the expertise of our members. Our members have a vital role to play in strengthening the voice of the water sector in shaping Australia’s future. AWA services and member benefits need to be better promoted and enjoy wider engagement across water users to galvanise support for AWA’s objectives.
water august 2014
The 3 Pillars of Value Driving Australia’s prosperity with water information, expertise and collaboration through: > Relevant Information > Professional Development > Promotion of Australian Water Capabilities For a more comprehensive look at the new business strategy and organisational structure please go to our website: www.awa.asn.au/ Strategic_Plan.aspx In the coming months AWA will engage widely with members to seek your views on taking the Association and the water sector forward – and to ensure the priorities and options selected for implementation reflect members’ most relevant matters. AWA welcomes your involvement as we develop and implement The 3 Pillars of Value. In doing so AWA remains committed to our core activities, including our many technical seminars, the annual Ozwater Conference & Exhibition and Water Journal, to enable members to share their expertise, influence community debate and champion their ambitions for a more water-sustainable Australia.
6
My Point of View
wiLL wE JUST wATcH AS THE wATEr-SciEncE GAp widEnS? Chris Davis – Technical Editor, Water Journal Chris Davis is an Honorary Life Member of AWA and Technical Editor of this Journal. Over a 41-year career, he has been involved with a variety of water activities, including operations, design, policy, research and planning. Cuts to funding for our national science icon, the CSIRO (Commonwealth Scientific and Industrial Research Organisation), made headlines recently as one of numerous victims of the Federal Budget. With the CSIRO brand being Australia’s best known and most widely trusted in science and technology, not surprisingly this caused quite a stir, rousing supporters of the organisation to spring to its defence. Disappointing as the proposed budget cuts may be, however, there is more to the story than meets the eye. Although the Federal funding cut added to the total reduction, CSIRO was in fact already engaged in a rationalisation and cost-cutting exercise. While a standard 2.5% efficiency dividend is being sought across the board, some areas are actually receiving more funds while others are seeing deeper cuts. The overall change will see CSIRO’s Average Staffing Numbers reducing from 5,523 in 2013–14 to 5,034 in 2014–15, a net loss of 489. Like all large bureaucracies, CSIRO has swung the pendulum to and fro over the years, from a cumbersome arrangement of dozens of separate divisions, to a matrix structure of fewer departments alongside so-called Flagships. This was the era of BHAGs – ‘big, hairy, audacious goals’ – soon after CSIRO’s seminal work to elucidate the mechanisms that drive Port Phillip Bay’s nitrogen cycle.
water august 2014
Although on paper the matrix structure seemed defensible, in practice it led to top-heavy staffing and duplication and was ultimately counterproductive. In spite of the difficulties, the Water for a Healthy Country Flagship was able to return a surplus each year and many valuable outcomes were achieved. The latest round of structural adjustments has morphed the organisation’s framework to a simpler model, with nine Flagships, of which Land and Water is one. Its directive will be to press on with critical national projects, mainly in a rural and catchment context. In the ’60s and ’70s, CSIRO’s water people concentrated on innovative technical solutions such as Sirofloc and Sirotherm, whereas in more recent times the organisation has contributed strongly to cutting-edge scientific solutions with social, environmental and economic dimensions and multi-disciplinary approaches. Some of the significant projects delivered were: Sustainable Yield Studies for the Murray-Darling, the Great Artesian Basin, Tasmania and Western Australia. Others included the Urban Water Security Research Alliance and the Goyder partnership, while a recent affiliation is focused on coal seam gas and water. A current hot topic is assessing resource development in northern Australia, which will demand not only excellent science but also the wisdom of Solomon in negotiating the fate of political ‘babies’, adored by their proponents. An emerging concern, though, is the urban water section, which is being disbanded, at least in Melbourne. Neither the rationale nor the final outcome is apparent, but many staff are already on the way out. Morale, understandably, is at an alltime low ebb.
safety solutions SELF CONTAINED EYEWASHES
sustainable Yield studies for the Murray-Darling was one of the major projects delivered by CsIRO.
LACK OF RECOGNITION CSIRO has not always effectively badged its contributions to projects, so recognition has sometimes been elusive. In the cut and thrust of profiling and positioning about urban water, in particular, it seems CSIRO has been outplayed by others. The CRC for Water Sensitive Cities is seen by some as fulfilling all the needs of cities; universities claim the academic high ground; while other entities have been strong on advocacy, but light on for science. Importantly, CSIRO has the ability to conduct dispassionate, evidence-based analysis of options for holistic water management – in short, to be the trusted advisor to government. Another dimension of this unfolding situation is that being between droughts has impacted the political climate as well. Not only has the sense of urgency been taken down a notch, but also the current Government is not necessarily sold on science generally. Add to that unfortunate coincidence the fact that Canberra-based champions for CSIRO are thin on the ground: the National Water Commission, long a supporter, is on its way out (although a Senate resolution to retain it was passed on 17 July); while the Department of Environment is being decimated and cannot be a strong ally. Against the backdrop of current challenges, it’s important to remember that CSIRO has always been financially challenged, since Government demanded that basic appropriation funds be supplemented by about a third of total revenue being externally earned. Carving an excellent scientific reputation is difficult to sustain while chasing funds from more prosaic activities – not to mention the basic challenge of continuous, productive deployment of thousands of scientists. On that topic, too, there are HR hurdles that have slowed or stalled the ability to make necessary adjustments to teams and to swing in fresh people. As a result, a mandate to rationalise the Water for a Healthy Country Flagship over a three-year period could not be achieved. What are the take-home messages from all this? My take, from a mainly water perspective, is that: • CSIRO is a national treasure and its 80-year contribution to science and technology should not be compromised by arbitrary cuts to funding (whether internally or externally driven); • CSIRO has a key ongoing role to play in a water research field that has many ephemeral players; but asserting national leadership, maintaining continuity and managing relationships are all going to take great political acumen;
Self Contained Eyewash Portable Gravity operated 15 minutes of continuous flow 35L tank capacity product code: EL483
Portable Eyewash/Body Spray Soft spray flow controlled eyewash outlets Stainless steel hand actuator and stay-open ball valve 45L tank incorporates a body spray product code: EL481* * trolley sold separately E7301-BK
Tobin 200ml Pocket Flask Enables washing in seconds Pocket size supplementary support to primary eyewash product code: TOB121
Tobin Eyewash Wall Stand Specially designed bottles give a soft flow Includes 2 x 1 litre bottles product code: TOB129
• We are currently between droughts: when the next one hits, it will be too late to start analysing how to manage it; • Urban water research needs a secure place in the science agenda and CSIRO’s input in that area is vital, to apply rigorous scientific and economic methods to both inevitable and potential problems.
FOR MORE INFORMATION CALL 1300 369 273 OR VISIT WWW.ENWARE.COM.AU
8
CrossCurrent
National The Australian Government has announced a third tender for groundwater purchasing to be conducted in the Murray‑Darling Basin’s Central Condamine Alluvium, with a budget of up to $10 million. The tender will close on 14 August 2014. For more information, including the Request for Tender document and application form, visit: www.environment.gov.au/node/36793
The Senate has passed a motion from Greens Senator Lee Rhiannon and independent Senator Nick Xenophon calling on the Federal Government to retain the National Water Commission (NWC). “The role the National Water Commission plays in assessing the National Water Initiative, auditing the Murray‑Darling Basin Plan, and driving water reform is vital,” said Senator Lee Rhiannon. “The Government must reverse its decision to shut down the National Water Commission – the only independent voice on water policy.”
The Bureau of Meteorology (BoM) has released its National Water Account 2013 Summary, a comprehensive record of water resources for the 2012–13 year. BoM Water Information Services acting Branch Head, Dr Grace Mitchell, said drier conditions in 2012–13 contributed to reduced inflows to storages and higher water use across much of Australia. To download the summary go to www.bom.gov.au
Australia’s National Water Initiative recently celebrated its 10th anniversary. To celebrate, the National Water Commission has launched an E‑Book and website including interviews with key stakeholders. AWA and WSAA recently issued a joint release on the importance of the NWI and the NWC.
New South Wales A Productivity Commission report has backed the NSW Government’s decision to lease almost half of the state’s electricity network, says Treasurer Andrew Constance. However, he rejected a recommendation to sell energy company Snowy Hydro. The report urged state and territory governments to consider privatising government‑owned power networks, retail businesses and major ports. Labor Opposition says the plan will result in higher electricity prices, job cuts and loss of dividends. Mr Constance said the report was a “strong endorsement of the recycling capital strategy the Baird Government has been undertaking.”
The NSW Government has commenced a one‑year trial of temporary water trading that will place downward pressure on water prices for Peel Valley irrigators and Tamworth residents. A factsheet outlining the trade rules is available from www.water.nsw.gov.au.
The State Government is being urged to consider setting up a new independent statutory authority to oversee the impact of coal seam gas, coal mining and farming on water resources. The recommendation from NSW Chief Scientist and Engineer Professor Mary O’Kane is the latest instalment of her wider Independent Review of Coal Seam Gas
water august 2014
Activities in the state. Professor O’Kane has identified locations where water monitoring equipment should be located around the state, including recommendations for sensors in areas considered high‑risk.
The Australian Competition and Consumer Commission (ACCC) has released its Final Decision on pricing for bulk water supplied by the State Water Corporation in the New South Wales Murray‑Darling Basin (MDB) in the 2014–17 period. The final decision incorporates the charges that the NSW Government recovers from irrigators through State Water for the Murray‑Darling Basin Authority. The decision will increase State Water bills for Murray and Murrumbidgee customers. Bills will fall for the majority of customers in other valleys.
More than 350 million litres of water will be saved annually following the completion of the first three Basin Pipe projects in the NSW Murray‑Darling Basin, Minister for Natural Resources, Lands and Water, Kevin Humphries says. Mr Humphries said the completion of the projects demonstrated the NSW Government’s commitment to delivering significant water infrastructure projects to ensure better outcomes for regional communities, irrigators and the environment.
Australian Capital Territory ACT Minister for Water, Simon Corbell, launched ACT’s Water Strategy at an AWA lunchtime event on1 August. The Strategy outlines priority outcomes, strategies and actions for the future of water management in the ACT, including catchment management, stormwater and flood management, water supply and services, water for the environment, recreational water and public health. The Strategy is available atwww.environment.act.gov.au
Queensland The Queensland Government has launched WaterQ: A 30-year Strategy for Queensland’s Water Sector. Queensland Water Supply Minister, Mark McArdle, said it was a strong plan that delivered on the Queensland Government’s election promise to provide better infrastructure and planning. “Queensland’s history, climate and growth demonstrates the critical need to properly plan for and manage drought and flood so families can continue to grow and prosper,” he said.
The Queensland Government has amended the Gulf Resource Operations Plan allowing the trade of licences for the Flinders and Gilbert River catchments. The department’s executive director of water policy, Lyall Hinrichsen, says the change allows greater flexibility for landholders. “The plan has now been amended so that existing water licences, including those recently made available through the unallocated water release process, can be traded,” he said.
University of Southern Queensland (USQ) researchers are embarking on a new stage of research into water and energy use efficiency on Queensland farms, thanks to a state government funding boost. USQ’s National Centre for Engineering in Agriculture (NCEA) has welcomed the Department of Natural Resources & Mines support of $89,190, which will be used to develop and promote water management technologies.
WHY NIBBLE WHEN YOU CAN MUNCH?
The Mono Muncher® range protects downstream equipment from blockages through reliable maceration of solids in a flow. Options on cutter sizes allow for specific particle size reduction and with large capacities available, there’s sure to be a Muncher® to suit your application. And with the benefits of Mono’s EZstrip™ technology on some models, including rapid release inspection covers and true ‘Maintain-in-Place’ servicing, the Mono Munchers® will take a big bite out of your maintenance costs. Mono Pumps...
At the heart of Australian ingenuity
For more information on the Mono Muncher® range, visit:
www.monopumps.com.au or email ozsales@nov.com
10
CrossCurrent Queensland irrigators in unsupplemented water areas could save up to $120 a year by reading their own water meters as part of a new Queensland Government initiative. Minister for Natural Resources and Mines, Andrew Cripps, said the statewide roll out of self‑reading of water meters would mid‑2014.
Queensland’s Energy and Water Ombudsman has been reappointed for another three years. Energy and Water Supply Minister, Mark McArdle, said Mr Forbes Smith would lead the Energy and Water Ombudsman Queensland through another term to July 2017. “Mr Smith will continue to provide free and independent dispute resolution services to energy customers across the State and to water customers in south‑east Queensland,” Mr McArdle said.
Victoria Simon Want has resigned as Head of Office at the Office of Living Victoria. His departure comes shortly after the resignation of the OLV’s Chief Executive Mike Waller. The OLV has been the subject of a long‑running Ombudsman’s probe amid concerns about its use of taxpayer funds and alleged breaches of the state’s procurement rules to hire staff and consultants. The Napthine government recently abolished the OLV’s status as a stand‑alone agency and has brought it under the control of the Department of Environment and Primary Industries.
The Victorian Coalition Government has introduced to Parliament a new Water Act that it says will streamline Victoria’s water laws, strengthen environmental water protection and safeguard the rights of water users. “The new Act will consolidate Victoria’s Water Act 1989 and the Water Industry Act 1994 into a single piece of legislation, and has been been drafted following comprehensive review of these Acts as well as extensive stakeholder and community consultation,” Minister Walsh said.
South Australia The Essential Services Commission of South Australia has released its Draft Inquiry Report into reform options for SA Water’s Drinking Water and Sewerage Prices. The Commission welcomes comment from interested parties on the draft findings and recommendations, which are required by 10 September 2014. A number of public forums are being held to explain the draft findings and recommendations. Interested parties can register at www.escosa.sa.gov.au.
Productivity, employment prospects and economic diversification in River Murray communities have been given a $17.5 million boost via two funding programs as part of the $265 million South Australian River Murray Sustainability (SARMS) Program. Deputy Prime Minister and Minister for Infrastructure and Regional Development Warren Truss and SA Minister for Regional Development Geoff Brock said the funding would be focused on regional economic development. Mr Brock said funded projects would achieve strong, innovative communities and a productive economy with a bright future in food and wine production.
water august 2014
Western Australia Water Corporation has replaced a 5.8 km section of the historic Goldfields Pipeline near Meckering to provide a more secure water supply for residents. The $14.6m project involved replacing a section of the original dual pipeline with a single pipeline buried beneath the ground. The original 557km pipeline was built in 1903 to transport water from Mundaring to Kalgoorlie. Today it feeds into a network of 8,000km of pipes, supplying drinking water to more than 100,000 people.
Hyden residents will soon have access to an innovative wastewater disposal system that will reduce the potential health and environmental impacts associated with septic tanks. Water Minister, Mia Davies, visited a home being connected to the state’s first Septic Tank Effluent Disposal (STED) system – a $5.8 million scheme made possible with $4.89 million from the State Government’s Royalties for Regions program.
Member News Victorian Minister for Water Peter Walsh has announced the appointment of a new director to the Coliban Water Board – David Richardson, Chief Executive Officer of Strategem. Mr Walsh thanked outgoing Director Andrew Skewes for his service to Coliban Water.
Hydroflux has signed an exclusive agency agreement with Flootech Oy of Finland for their advanced MBBR technology. The technology represents state of the art bio‑process solution to both industrial and municipal wastewater applications.
Suez Environnement, through its subsidiary Degrémont, has completed the acquisition of Process Group. Based in Melbourne, Singapore and Abu Dhabi, Process Group specialises in engineering, design, fabrication, commissioning of equipment for the global oil and gas industry. Founded in 1978, the company has 120 employees and achieved an annual turnover of about 60 million euros.
Beca has appointed James Prothero as Business Director, Water and Environment. James is based in Sydney, with a business wide responsibility to expand its services and client offering within the water sector and develop strategies to grow Beca’s market share.
Veolia Water Australia has been awarded a contract to operate and maintain Hunter Water’s 25 treatment plants. The $279 million contract is the largest ever awarded by Hunter Water and comes after a 12‑month tender process overseen by independent procurement specialists to ensure the integrity of the process.
TRILITY has announced its appointment as operator of four water treatment plants in regional Victoria. TRILITY will operate the plants for the next 13 years in conjunction with the plants’ new owner, AMP Capital, under an existing 25‑year agreement with the Grampians Wimmera Mallee Water (GWMW) in western Victoria.
Your digital journal is now available!
NOW YOU CAN READ WATER JOURNAL BEFORE IT’S EVEN PRINTED... AND ACCESS BACK ISSUES AT THE CLICK OF A BUTTON! www.awa.asn.au/Journal/
12
Industry News
NORTHERN QUEENSLAND SUSTAINABLE RESOURCE FEASIBILITY STUDY Acting Prime Minister the Hon. Warren Truss recently released the Northern Queensland Sustainable Resource Feasibility Studies, completed by GHD to test the feasibility of major agriculture and power developments in the region, and to identify the economic impacts of the most feasible projects. GHD’s Project Director John O’Brien said the studies undertaken would provide valuable insight to the technical, commercial and economic drivers of major agriculture and power generation investment in the region, and Northern Australia more broadly. “These studies identify the immense natural resources available in Northern Queensland, as well as the challenges in developing large-scale projects, particularly agricultural projects that rely on multi-generational water infrastructure. During our investigations we noted the policy focus on northern Australia, regional Queensland, agricultural production and electricity prices – all issues relevant to the objectives of the projects assessed,” John said. “There are some major challenges financing water infrastructure to support new large-scale irrigated agricultural projects because that infrastructure is designed to operate and will provide economic value to the community for more than 100 years. This is well beyond conventional financing horizons. Global markets, investor characteristics and our natural resources are favourable to large-scale irrigated agriculture, but the expectation that a single project can bear the entire cost of 100-year water infrastructure is a critical issue to address.” John said GHD was proud to have been appointed to conduct these studies given the company’s long history in North Queensland and strong belief in Northern Australia’s economic potential.
TED GARDNER AWARDED FOR CONTRIBUTION TO IRRIGATION INDUSTRY CQUniversity Adjunct Research Fellow Professor Ted Gardner has been awarded Irrigation Australia’s MacLean Iedema Award ‘for outstanding individual contribution to the irrigation industry’. Presented every two years, the Award includes a cash prize and commemorative plaque. Professor Gardner, who is a member of Water Journal’s Editorial Committee, is a retired scientist who spent most of his working life as a research scientist in the Queensland Department of Natural Resources and its many predecessors. He started his career as an irrigation soil physicist in the Emerald and Burdekin irrigation areas, and meandered through various reinventions,
water august 2014
including effluent irrigation and other alternative water sources. One of his proudest team achievements was the MEDLI effluent irrigation model, which is still used today to design sustainable irrigation schemes. Other activities included a strong experimental focus on alternative ways to use recycled water, and a passion to communicate these findings to industry stakeholders. Professor Gardner finished his full-time career leading a research team in CSIRO, which examined alternative urban water sources, especially rainwater tanks. He is currently co-editing a book on this subject, as well as being active in student mentoring at a number of regional universities. At CQUniversity, Professor Gardner is aligned with the School of Medical & Applied Sciences and co-supervises two postgraduate students. The MacLean Iedema Award is so-called because the industry lost two of its leading lights when Scott MacLean and Don Iedema were killed in a light plane crash in Victoria in 1995. Don was a senior executive with the large retail irrigation supply chain, Aquafield McCracken, and had played a significant role in the company’s expansion. Scott MacLean was the group’s General Manager and, with Don, played a role in the establishment of Irrigation Australia (IAL). Scott has been described as a natural leader and was a national chairman of IAL in its early years. It was his vision to create an expo to bring together the best the industry has to offer. The Irrigation Australia event is now held every two years and moves between major cities. The award is presented at the event.
WILLIAM LAWSON LINK ON PROSPECT RESERVOIR HERITAGE SITE CONFIRMED A heritage site found at Prospect Reservoir late last year has been confirmed as part of the estate of the famous Australian explorer William Lawson. Sydney Catchment Authority (SCA) Heritage Officer, Kate Lenertz, said the site was revealed after the lake was lowered 3.8 metres below full storage level to allow a multi-million upgrade to the dam to take place. “At the time we were uncertain if the half-acre site – comprising brick footings, wells, fireplaces and scattered artefacts – was built for William Lawson who resided at Veteran Hall just a few hundred metres up the hill,” she said. “We can now confirm, based on the archaeological report, that it is almost certain that the structure was built for William Lawson after he purchased the land from landholder Fergus Gallagher in 1811. “There is no certainty what these buildings were, but evidence suggests it may have been a stables or some other multi-roomed structure and included a chimney, three wells and timber fence lines.” Ms Lenertz said that while the reservoir levels remained low throughout the first half of 2014, SCA heritage experts made two new colonial finds. “These were considerably smaller sites than the original find,” she said. “The most substantial is just 700 metres as the crow flies further north and includes a basic fireplace. It is in direct line-of-sight to both the original discovery and Lawson’s Veteran Hall.”
13
Industry News The second site, which is another kilometre further away, is comprised mostly of scattered bricks and some pottery and coins. “While neither is as substantial as our first find, they contribute more to the picture of colonial settlement prior to flooding of
WWEM 2014 TO BE HELD IN TELFORD, UK
Prospect Reservoir in the 1880s,” Ms Lenertz continued. “The additional sites were definitely not part of Lawson’s original grant, but were later purchased later by Lawson or his family as the estate grew.” Prospect Reservoir is currently being refilled as construction works move into the next phase, and the recently discovered artefacts are being submerged again. “The archaeologists have advised the best conservation technique is to actually leave the artefacts and relics in situ and allow them to be submerged again,” said Ms Lenertz. “We’ve surveyed and photographed the key elements and because they are within protected Special Areas they are not threatened by public access. They have survived 125 years underwater and been exposed from time to time during major dewatering of the reservoir.” To allow for the remainder of the upgrade to take place, the Prospect Reservoir grounds will continue to be closed to the public until the end of 2014.
WWEM 2014, the international Water, Wastewater and Environmental Monitoring Conference and Exhibition, will take place at the Telford International Centre in the UK from 5–6 November. The first day’s Conference will focus on industrial and municipal monitoring, while the second day will address some of the key issues relating to sampling and laboratory analysis. The event, which is the sixth in a series of successful environmental monitoring events, will provide delegates with the latest information on the techniques, technologies, methods, standards and regulatory requirements that relate to the monitoring that takes place both on-site and in the laboratory, covering sampling, field analysis, gas detection and continuous water and wastewater monitoring applications. In addition to the main Conferences, delegates will be provided with access to over 80 workshops, a Flow Demonstration area, forums on Flow and SMART Water, and an exhibition featuring over 130
august 2014 water
14
Industry News stands representing more than 250 of the world’s leading providers of test and monitoring equipment and related services. CPD points will be awarded to Conference delegates, with the cost to attend being £55 per day. However, registration for the event is free of charge and pre-registered visitors are provided with free access to the exhibition and to the workshops, in addition to free on-site parking, and complimentary lunch and refreshments.
His PhD project is “Polysaccharide Fouling in Reverse Osmosis and Forward Osmosis Desalination and Its Alleviation”. The research compares polysaccharide fouling in RO and FO systems in desalination, elucidates the fouling mechanisms and develops new strategies to reduce polysaccharide fouling. The NCEDA congratulates John on his achievement. The winning poster can be downloaded from the NCEDA website.
For more information go to www.wwem.uk.com
NCEDA SCHOLARSHIP RECIPIENT WINS BEST POSTER AWARD John Xie, a recipient of NCEDA supplementary scholarship, was the winner of the Best Poster Award at the Singapore International Water Week – Water Convention. His entry competed with over 200 posters from researchers around the globe and pipped the three runners-up from MIT, Oxford University and National University of Singapore. John obtained a Bachelor degree and Master degree in Environmental Engineering in China. He was granted a Murdoch International PhD scholarship from Murdoch University and a supplementary PhD scholarship from NCEDA, under the supervision of Professor Goen Ho, Dr Linda Li, Dr Lucy Skillman and Dr Ralf CordRuwisch. He is a member of the International Water Association (IWA).
SEQWATER CEO RELEASES MEDIA STATEMENT Seqwater relased the following media statement in July 2014 regarding the filing of the flood class action: Seqwater remains acutely aware of the impact of the January 2011 flood event and the devastation caused to many in our community. Seqwater is confident its management of the event will continue to be shown to have significantly reduced the impact of the flood as the matter progresses through the court process. Seqwater would like to make the following points in relation to the January 2011 event: • Two major rain episodes, each generating the equivalent of a 1974 flood, occurred across Wivenhoe and Somerset Dam catchments less than 30 hours apart. The rainfall also generated major flood flows from catchment areas downstream of the dams. • The Queensland Floods Commission of Inquiry made no finding of negligence against Seqwater. • The independent experts at the Commission of Inquiry supported Seqwater’s actions. The Commission’s own expert concluded that, in the circumstances, Seqwater had achieved close to the best possible flood mitigation result. • The independent review by the United States Bureau of Reclamation and the US Army Corps of Engineers also supported the decisions made and actions undertaken by Seqwater. • Seqwater has never wavered from its belief that our engineers did an extraordinary job in the most difficult and demanding of circumstances. Our position has not changed. Seqwater will now examine the statement of claim in detail.
DRINKING WATER FOR DONALD, MINYIP, RUPANYUP AND WYCHEPROOF GWMWater has completed the upgrade of the Donald, Minyip, Rupanyup and Wycheproof town water supplies to drinking water quality. Works on the project started in October 2013 and were completed in June 2014. Managing Director Mark Williams said that each town was now being supplied with drinking quality water piped from a water treatment plant in a nearby town. Donald is receiving its water from the St Arnaud Water Treatment Plant via a 39 km pipeline, Minyip from the Murtoa Water Treatment
water august 2014
15
Industry News Plant via a 24 km pipeline, Rupanyup from the Murtoa Water Treatment Plant via a 15 km pipeline, Wycheproof from the Charlton Water Treatment Plant via a 26 km pipeline, and Jeparit will also soon be receiving drinking quality water from the existing Rainbow Water Treatment Plant, with the project expected to be completed in the next two months. “The decision to pipe water to these towns utilised spare capacity in the existing water treatment plants, providing significant cost savings compared to the traditional solution of building plants in each town,” Mr Williams said. The entire project will provide drinking quality water to over 3,000 people and has been completed at a cost of approximately $12.5 million. The project has been supported by the Victorian Government’s Country Towns Water Supply and Sewerage Fund.
FACING UP TO WATER CHALLENGES IN THE MINING INDUSTRY The complex and demanding issues that mining companies face in terms of water would be best met through close collaboration between the companies and water service providers. This was the conclusion of a Panel Session held during the recent Singapore International Water Week, one of the key water industry
events in the Asia-Pacific Region. The session, facilitated by Carmine Ciccocioppo, Chief Operating Officer of Australian-headquartered desalination and water solutions company Osmoflo, with panel members including senior executives from global water companies, discussed water management in the mining industry. Osmoflo has been a long established supplier of water solutions and systems to the resources sector in Australia and overseas. Its systems make brackish or otherwise contaminated water from bores, rivers, dams and the ocean fit to drink, or suitable for process needs including high-purity applications.
DESIGN BUILD OPERATE MAINTAIN wigroup.com.au
august 2014 water
16
Industry News “Everyone recognises that water is vital to mining, but there are differences of opinion in how to face the various and ever-changing challenges it presents. For example the increasingly heavy hand of regulation is making its presence felt in more and more countries,” says Mr Ciccocioppo. “Regulation now covers everything from supply, abstraction, wastewater or used water discharge to ongoing protection of the environment from possibly contaminated tailings dams for years after the miners have moved on. “At the same time mining companies are under pressure to improve their efficiency and reduce their operating costs,” Mr Ciccocioppo says. “The question of risk allocation relating to water is also becoming a key issue. While some companies hold the view that water management is very important but not a core activity and is better left to qualified outsourced providers with the skills to build, operate, maintain and possibly even finance required water infrastructure, a minority of companies take a different approach. They see the issue as too important to be left to any outsiders and wherever possible are investing heavily in building water related expertise and capability. “While there is merit in both these arguments, specialist companies like Osmoflo have years of experience in providing water solutions in the most remote locations and successfully treating source water containing all sorts of elements that make it unsuitable for use in its raw state. And more often than not, that experience leads to the job being done in a highly cost-effective manner,” Mr Ciccocioppo claims. Osmoflo is the largest Australian headquartered manufacturer of desalination plants for industry and community applications and also of solutions using other water-related technologies. The company maintains overseas offices in the United Arab Emirates, India and Chile.
BARWON WATER PROJECT FINALIST IN UN WORLD ENVIRONMENT DAY AWARDS The Barwon Water Biosolids Management Project has been named a finalist in the 2014 United Nations Association of Australia World Environment Day Awards. The project will provide an environmentally sustainable, long-term management scheme for the beneficial use of biosolids produced at Barwon Water’s regional water reclamation plants. Located south of Geelong, adjacent to the existing Black Rock Water Reclamation Plant, the project involves the construction of a facility to safely dry and pelletise biosolids so that they achieve the highest possible treatment quality; grade T1. The project was delivered as a Public Private Partnership (PPP). Plenary Environment has financed, designed and built the facility and has contracted the operations and maintenance to Water Infrastructure Group for a 20-year term. Peter Everist, Water Infrastructure Group Strategic Growth and Marketing Director, said that the PPP approach was critical in introducing a new technology to Australia and delivering this Australian-first facility. “The small footprint, fully enclosed thermal drying facility is the first of its kind in Australia and the largest in the South Hemisphere to achieve 90% de-watering and T1 Treatment Grade pelletised biosolids, “ he said.
Water Minister Peter Walsh with the project team at the official launch of the Barwon Water Project.
water august 2014
17
Industry News “It produces very dry pellets suitable for farm fertiliser and can be applied using standard fertiliser spreaders. The pellets are safe to handle, easy to transport and can be reused as farm fertiliser immediately after processing.” “Instead of being stockpiled for a few years, with the associated odour and greenhouse gas emission issues, the new fully enclosed facility converts biosolids to pellets within hours. The small footprint of the facility also dramatically reduces the amount of land required to treat biosolids compared to traditional air drying and storage.” The Barwon Water Biosolids Management Project is a model for sustainable biosolids management at a regional level that successfully addresses the environmental issues associated with biosolids stockpiling, disposal and reuse.
The third delivery of the Borneo Water & Wastewater Exhibition will create greater awareness of the issues of water resources and water supply and the challenges that may be faced. The scientific and technical programs will focus on finding solutions to balance Malaysia’s already stressed water supply with increasing demand, innovative and sustainable partnerships in financing and managing water and wastewater, latest technologies in drinking water, wastewater and solid waste management, protecting eco-systems and water catchments, coping with climate change and sustaining water resources including the water-food-energy nexus and green technology. For more information on attending, exhibiting or submitting papers, please email bwwe2014@console.com.my or visit www.mwa.org.my
ARUP APPOINTED FOR CITY TO THE LAKE DEVELOPMENT
BORNEO WATER & WASTEWATER EXHIBITION 2014
The ACT Land Development Agency, on behalf of the ACT Government, has appointed Arup as lead consultant for the City to the Lake Estate Development Plan. This mixed-use development is one of Australia’s largest urban renewal projects and builds on the vision of Walter Burley Griffin to foster the growth and prosperity of Australia’s capital.
Water Security and Sustainability is the theme of the Malaysian Water Association’s Borneo Water & Wastewater Exhibition 2014, which will take place 19–21 November in Miri, Sarawak. Despite receiving plenty of rainfall (annual average 3000mm), Malaysia has begun feeling pressure on its water resources, particularly during a recent drought period that resulted in water rationing in some areas earlier this year. A more serious crisis could occur if El Niño strikes again this year. This means that building water security and ensuring water sustainability has become an issue of vital importance.
The work will include the creation of a new lake-front at West Basin, a significant residential development, and a new stadium, convention centre and aquatic centre for the city. Arup has been tasked with design development and delivery of final construction documentation for the first stages of City to the Lake, as well as concept design for the balance of the site. The new precinct will increase the connectivity of Canberra to its natural assets, providing sequential redevelopments of the corridor between the city and Lake Burley Griffin. The initial West Basin lakefront portion will include a new boardwalk with pavilions for restaurants and cafes and a new residential, retail and commercial precinct. These will be linked through an open space network including pedestrian and cycle paths, and rainwater gardens.
Scholarships
watercentre.org/iwc-scholarships
Master of Integrated Water Management • Full-tuition scholarships ($49,920) for full-time or part-time/distance study - receive a co-badged degree from four leading Australian universities • Apply by 1 October and commence study in Semester 1, 2015
Water Leadership Program • Full ($10,000) and half ($5,000) scholarships for emerging leaders at the project to middle management level. Nine-month leadership development program (two sessions in Brisbane and the rest online/at distance) • Apply by 15 September and commence the program in December 2014
august 2014 water
18
Industry News
LANDMARK SHUTDOWN FOR WORKS AT HISTORIC MT CROSBY WATER TREATMENT PLANT Seqwater has completed a package of works at the historic East Bank (Mt Crosby) Water Treatment Plant to ensure a continued safe, secure and reliable water supply for the greater Brisbane and Ipswich areas. Seqwater Chief Executive Officer Peter Dennis said the East Bank water treatment plant, which originally opened in 1882, was an essential part of Seqwater’s water supply network, providing all of Ipswich city’s water and about half of Brisbane’s supply on an average day. To complete the critical works, the plant had to be shut down for three days, which was the first time in over 50 years that this had occurred at East Bank. Mr Dennis said shutting down and fully draining a plant of its size in order to achieve the necessary isolations to undertake the works, was a significant undertaking. “The works were necessary to replace and maintain ageing infrastructure and improve the plant’s operability, reliability and safety,” Mr Dennis said. “It’s no simple matter to take such an essential piece of the bulk water supply network offline and the temporary shutdown of the plant followed months of careful planning to ensure water supply was maintained across the whole network. “To minimise disruption to the water supply network, staff worked in rolling shifts around the clock from June 2 to 4, completing a number of different projects at the same time. Despite being a highly complex project, with numerous skilled trades working to a tight schedule, the project was completed without a hitch.” Mr Dennis said the work would help ensure continued high water quality as well as the safety of staff operating and maintaining the plant. “A key component was the replacement of valves to improve water and flow management,” he said. “Sludge plant flow control and measurement was completed to improve the ability to manage the flow and volume of water travelling through the plant. We also took the opportunity to undertake some initial work in preparation for the installation of a new lime system in the future. Other maintenance and inspection works were also undertaken while the plant was offline.” A new roof was installed on the high level reservoir prior to the shutdown of the plant. “The heritage-listed reservoir was built in 1882, with a floating roof installed around 30 years ago. This floating structure has now been replaced with a fixed roof, which will improve water quality. The Mt Crosby Historical Society was consulted throughout the project to ensure it went smoothly.”
water august 2014
JOURNEY TO THE CENTRE OF THE EARTH The Earth’s interior could contain more than three times the amount of water in all our oceans combined, existing within the structures of silicate materials that are stable at the prevailing conditions deep inside the Earth. New research from ETH Zürich has helped to elucidate exactly how deep water gets transported into the Earth’s interior. Water is fundamental for processes that occur at the Earth’s surface, but also plays a critical role in many geological processes occurring deep inside it that shape its evolution. Small amounts of water incorporated into the structure of minerals have a major effect on their stability, behaviour and phase equilibria. Global processes such as mantle convection, plate tectonics and naturally occurring catastrophic events such as earthquakes and volcanic eruptions are strongly influenced by the activity of this water. Water is reintroduced into the Earth’s interior by hydrated tectonic (oceanic) plates that return into the mantle in subduction zones, and is released when hydrous minerals/phases are decomposed due to the high pressure and temperature of the Earth’s interior. Much of this water returns to the surface by volcanism, but a large fraction of it is retained in newly formed high-pressure hydrous phases that are stable at much higher depths, opening the possibility for water to recirculate deeper into the mantle beyond 400km depth. However, the exact amount of water stored in the solid Earth, and how (and how much of) this water is recycled back to the surface, remains obscure. Carmen Sanchez-Valle, Assistant Professor of Experimental Geochemistry and Mineral Physics at the Swiss Federal Institute of Technology, has worked with her team to develop several novel analytical techniques to investigate this environment. “Through learning about the Earth’s interior, we become more aware of what actually occurs on the surface,” she explains. A group of dense hydrous silicate phases discovered in laboratory experiments in the mid-1960s – the so-called alphabet phases (phase A, E, D and superhydrous B) – are plausible candidates for the transport of water at depth due to the large stability field. The physical and chemical properties of these materials, obtained through mineral physics studies, are fundamental to revealing the deep water cycle. A device called a diamond‐anvil cell (Figure 1) is the primary tool used by researchers to replicate extreme conditions that exist at
Figure 1
19
Industry News the Earth’s interior, and explore how hydrous phases behave. By powerfully compressing micrometric-size samples between the flat surfaces of quarter‐ carat diamonds, the apparatus authentically simulates pressure conditions down to the Earth’s core. To recreate the infernal Figure 2 temperatures present in these realms, heating elements or infrared lasers are introduced to the tests. “Crucially, the diamonds are transparent, which means that brilliant X-rays produced by synchrotron sources and laser analysis can be used to probe the physical and chemical state of samples while they are submitted to extreme pressure and temperature conditions,” adds Sanchez-Valle. “These experimental simulations provide us with a virtual window into the deep Earth.” Fortunately, seismic waves can be simulated within the team’s facilities. Using a unique laser spectroscopy called Brillouin scattering spectroscopy (Figure 2), the speed of seismic waves and elasticity of materials can be monitored under pressure, divulging their waterbearing qualities. The team also uses the brilliant X-rays produced at
synchrotron sources to monitor the development of textures in hydrous materials deformed at conditions that mimic those of subducting slabs penetrating in the lower mantle. “Our combined studies on hydrous phases have allowed us for the first time to interpret seismic anomalies observed in deep subducted slabs,” says Sanchez-Valle. “The work has shown that hydrous slabs penetrating below the transition zone in areas such as Tonga could contain at least 1.2% in weight of water bound to dense hydrous phase D. The dehydration of phase D at greater depths is a potential mechanism to activate very rare (and less damaging) deep focused earthquakes, and the water released into the lower mantle has important consequences for the geodynamical and geochemical evolution of the deep Earth.”
SEQWATER TRAINEE OPERATOR NAMED QUEENSLAND’S YOUNG OPERATOR OF THE YEAR Seqwater Trainee Water Treatment Plant Operator Sarah Walton has been named Qldwater Queensland Young Operator of the Year 2014. Sarah, who graduated from the University of Queensland in 2004 with a Bachelor of Science, worked in the field of geophysics in western Queensland mines for seven years.
THINK
POLYMASTER HPH POLYMASTER For the safest and most effective solution for storing and dosing chemical, Polymaster dosing tanks are made from a Polyethylene material that won’t corrode like some other storing methods. A dosing pump mounted to a small Polymaster dosing tank is the ideal, easy to use set up for dosing chemical. When you think dosing tanks, think Polymaster.
Call to discuss your chemical dosing application with us today august 2014 water
1300 062 064
20
Industry News But it was her passion for water which led to Sarah securing the role of Trainee Operator at Seqwater last year. “I felt it important to
PHILMAC WINS NATIONAL AWARDS Specialist pipe fittings and valves manufacturer Philmac.has won
start with the basics in
two major national awards and been named runner-up in a third.
the water industry and to
The company was named Supplier of the Year at the annual ProWater
learn from experienced
National Conference held in June on the Gold Coast, the second
operators, so I was happy
consecutive year Philmac has taken out the title. Philmac also won
to embark on a trainee
Trade Supplier of the Year within the plumbing category at the
role, despite my previous
recent 2014 Home Timber and Hardware Group National Trade
experiences,” Sarah said.
Awards held in Cairns. The company was also named runner-up at the ThinkWater
Sarah began by shadowing operators and
Australia National Supplier of the Year Awards held on the
studying for her Certificate
Gold Coast.
II in Water Operations
“Winning these coveted awards run by the leading operators
(Water Treatment), and has quickly progressed to assisting run
within our industry is a real vote of confidence in the high standards
the water treatment process for the North Pine plant’s day-to-day
we set for our products and service,” Philmac GM Marketing &
operations.
Product Development, Jason Mitchell said.
Having completed her Certificate II in Water Operations (Water
Established in 1929, Philmac is an Adelaide-based designer and
Treatment), Sarah is now studying a Masters in Environmental
manufacturer of compression fittings and valves for polyethylene
Science, which she will complete at the end of the year. Sarah’s
(PE) pipelines, with distribution centres across Australia, the United
career goal is to work in water catchment management.
Kingdom, and soon in the United States.
NatioNal operatioNs CoNfereNCe affordability, liveability aNd seNsitivity – operatioNs iN the tweNty teeNs
28 To 30 OctOber 2014 cairns cOnventiOn centre
registratioN Now opeN
With the tightening of funds for water operations nationally, it is imperative that we innovate and optimise the way we work like never before. This will ensure we continue to provide best value for money for our customers, while not reducing our quality standards.
Registration and full program details available at
www.awa.asn.au/operators2014
With the 2014 National operations Conference being held in Cairns and the mounting damage of the nearby Great Barrier Reef as a reminder, we are taking a strong focus on the environmental obligation in the sustainability of our operations. As emerging industries come to fruition, e.g. mining, agribusiness and tourism, we need to ensure the future national prosperity is balanced carefully with sustainable water usage and environmental protection.
austraLia’s Largest Fusion oF Business and enVironment the event for industry, government and the environmental sectors to gather to shape policy and progress on sustainable enterprise. • 5 renowned keynote speakers plus a massive 3-day program of experts • Professional development workshops and technical tours • Concurrent streams across energy, waste, water and clean air • Facilitated one-on-one meetings with keynotes and sponsors • Networking opportunities with researchers, government, business leaders, practitioners and policy makers KEYNOTE SPEAKERS:
Jonathan trent OMEGA Project Scientist, NASA Ames Research Centre
richard J. Pope Vice President, ARCADIS, New York
Benjamin Hewett SA Government Architect & Executive Director of the Office for Design and Architecture SA
don’t miss out register today
dr Felicity-ann Lewis, President ALGA, Mayor of Marion
Jon dee Founder & MD DoSomething! Founder Planet Ark
WASTE • WATER • CLEAN AIR • CLEAN ENERGY
Conference, Expo, Workshops & Tours 17 - 19 Sep 2014 • Adelaide Convention Centre
aysr www.enviroconvention.com.au w h Patr bette fo ess
busin
www.enviroconvention.com.au A joint venture between:
ENVIRO’14 Partner Organisations:
Government Partner:
Media Partner:
22
Young water Professionals
The IrresIsTIble Force Paradox Justin simonis – aWa yWP National Committee President Before I get to this edition’s topic, it is with a mixture of sadness and joy that I pay tribute to another integral cog in the Young Water Professionals wheel. Kim Wuyts, AWA Program Manager for the YWP Specialist Network, has moved on to take up a role with Medicines sans Frontiers. Kim’s contribution to the development of the YWP Specialist Network cannot be adequately measured. On behalf of the National Representative Committee (NRC) I‘d like to thank Kim for her commitment to the YWP network, congratulate her on her new role and wish her all the best for the exciting new challenges ahead. The ‘irresistible force paradox’ is a story used to describe the impossibility of an unstoppable force meeting an immovable object. To paraphrase the ancient Chinese proverb, there was once a salesperson with a spear that could pierce any shield, and a shield that could stop any spear. When asked by a passerby what would happen if the spear was thrown at the shield, the salesperson could not answer. The story endeavours to explain the contradiction of an irresistible force striking an immovable object, a theme that, in one form or another, still exists in many different cultures. So how is it relevant to us as YWP, the NRC, members of the Association and, ultimately, AWA itself? In market conditions that have given rise to the term “sweat your assets”, seen a large-scale downturn in the professional services market (flowing onto the construction market) and made consolidation the new buzz word, you could be forgiven if you thought there wasn’t a lot going on in the water industry. On the contrary, the relevance of this story to ours is that change itself is the irresistible force, one of the few constants, aside from death and taxes, that can be relied upon.
water august 2014
It is also the theme that underpins the industry of change management. If you prescribe to the change management theory you believe that those who adapt to change survive and those that don’t adapt, don’t. It’s my belief that is our willingness as members of the Association to accept and embrace change that will define if we are to be ”the shield” (an immovable object), or a dynamic association that will survive and thrive.
Fresh eyes, Fresh ideas It’s not uncommon for new management to make changes within an organisation. Indeed, this new burst of energy and abundance of ideas, from being able to look at an organisation with “fresh eyes”, can be one of the big drivers for their being selected for the role. Over the past few months new AWA CEO Jonathan McKeown and the AWA Board have been working to develop a new business strategy for the Association to ensure that it thrives rather than survives in the current market. As the NRC we can draw on the momentum that this energy has created to help us with our own mission of reinvention as we strive to ensure that the Committee also stays relevant to the members of the specialist network. Our challenge is to deal with the level of uncertainty that change inevitably brings, but our path will be made easier by the air of change already in the Association and the excitement and energy that it can foster. The key to our success is to create ownership. My goal is to foster a sense of ownership by involving in this refocusing session not only each NRC member but also the branch Chairs. I also welcome feedback from any AWA member as to the future direction of the NRC and the role it can play to help advocate the issues of young professionals across this industry. Please email ywp@awa.asn.au.
23
awa News Hear from five renowned international and domestic keynote speakers: Jonathon Trent, OMEGA Project Scientist, NASA Ames Research Centre; Richard J Pope, Vice President, ARCADIS, New York; Benjamin Hewett, SA Government Architect & Executive Director of the Office for Design and Architecture SA; Dr Felicity-Ann Lewis; President ALGA, Mayor of Marion; and Jon Dee, Founder & MD DoSomething!, Founder Planet Ark.
aWa aNd Wsaa aPPlaUd The NWI The Australian Water Association (AWA) and Water Services Association of Australia (WSAA) have applauded the work done under the National Water Initiative over the past decade.
To register or find out more please visit enviroconvention.com.au
AWA Chief Executive, Jonathan McKeown and WSAA Executive Director, Adam Lovell said the National Water Initiative continues to provide a national focus on water, one that should not Jonathan McKeown be lost with the closure of the National Water Commission later this year. “With water a crucial economic driver upon which Australia’s future productivity and prosperity will be developed, the National Water Initiative provides the guiding principles for further development, particularly in regional and rural areas,” said Mr McKeown.
adam Lovell
“In the last 10 years, the Initiative has formulated a national approach to water management which has been important through the challenges of droughts, floods and population growth, with water users, industry and the environment reaping the benefits,” said Lovell. In congratulating the National Water Commission on its work in driving progress under the National Water Initiative, both organisations also expressed disappointment in the closure of the Commission. “As an agency that has provided fearless advice, monitoring and leadership on water management in Australia, the Commission’s closure weakens our ability to engage Australians on water management,” said Mr McKeown. “As Australia’s blueprint for water reform, the National Water Initiative now needs renewed commitment from both the private and public sectors. It is crucial that the wider community is fully engaged in using water sustainably in an effort to drive Australia’s economic future and the renewal of the National Water Initiative is a key part of this,” said Mr Lovell. WSAA and AWA congratulated the staff at the National Water Commission for their work in implementing the National Water Initiative and look forward to the Commission’s comprehensive review of progress of the Initiative to be released at AWA’s National Water Policy Conference on 15 October 2014.
oZWaTer’15 call For PaPers NoW oPeN AWA is calling for abstract submissions for Australia’s international water conference and exhibition – Ozwater’15. If you’re a water professional or have an interest in water, this is your opportunity to share ideas, research or an initiative, and encourage innovation and professional development collaboratively. Don’t miss out – submissions close 28 August 2014. To view the conference themes and submit your abstract, visit www.ozwater.org and download the Call for Papers brochure.
aWa coNGraTUlaTes Qld’s WaTer sUPPly MINIsTer oN release oF 30-year sTraTeGy AWA congratulates Queensland’s Water Supply Minister, Mark McArdle, and the Department of Energy and Water Supply on the release of ‘WaterQ, a 30-year strategy for Queensland’s water sector’. AWA acknowledges that the task of synthesising a long-term water sector strategy to seven priorities is a difficult one, and we believe that overall the strategy clearly supports increased productivity, economic growth, healthy communities and the environment.
eNVIro’14: PaThWays For beTTer bUsINess
AWA Chief Executive, Jonathan McKeown, said that for Queensland, and indeed Australia, to reach its full economic and social potential it will require significant expansion of land and development and population growth, and that these major drivers of economic prosperity need to be balanced carefully with sustainable water usage and environmental protection.
ENVIRO’14 is where industry, government and the environmental sectors gather to shape policy and progress on sustainable enterprise. This three-day program, held from 17–19 September at the Adelaide Convention Centre, includes workshops and technical tours; concurrent streams across energy, waste, water and clean air; facilitated one-on-one meetings with keynotes and sponsors; and networking opportunities with researchers, government, business leaders and policy makers.
“The Australian Water Association sees ‘WaterQ’ as a great blueprint for the future of water in Queensland and we look forward to working with the Government in its implementation. The Association is keen to learn more about how the Queensland Government intends to deliver the actions outlined in the Strategy, to maximise these economic activities and emerging industries. The 30-year Strategy needs to be owned by the community as an effective process of sustainable water management that delivers economic prosperity for the State.
august 2014 water
24
awa News “AWA is particularly pleased with the focus the Queensland Government has placed on developing our knowledge and skills in the sector, and exploiting these through innovation and technology,” said Mr McKeown. “AWA is also focusing on the promotion of the water industry’s innovative technologies and we look forward to working with the Queensland Government as they further realise these actions, particularly the Innovation Panel.” The Association is, however, disappointed that drinking recycled water was noted as being off the table as a supply option. “The Association believes in the importance of having a diversified portfolio of supply options, one of which is recycled water. It is disappointing that the 30-year Strategy rules it out completely, thus removing the opportunity for customers and communities to make fully informed decisions,” said Mr McKeown. The Association looks forward to working with the Queensland Government and our broad industry members to ensure that details are further developed, key actions are implemented and priority outcomes are achieved.
• $500,000 to undertake feasibility studies and prepare business cases for priority water security infrastructure projects that enhance town water security across regional NSW. The Association agrees with the Government that improving regional infrastructure now will not only assist in drought-proofing regional NSW, but also has the potential to improve the productivity of our agricultural land. However, AWA Chief Executive, Jonathan McKeown, says that it is imperative that the NSW Government doesn’t just look to dams to satisfy water security needs. “Dams are not the only solution to securing water supplies in our regions. The Government needs to ensure that it makes informed decisions on the best water security opportunity for each location. “A portfolio of options including water efficiency programs, alternative water sourcing and education are all other mechanisms that should be considered, aside from just building expensive new dams that have the potential for negative environmental consequences. “Further, it needs to be ensured that investment is not just spent in large water infrastructure projects, but also looks to address the deficiencies in drinking water quality, wastewater treatment and capacity to meet the growing populations of our regional areas,” said Mr McKeown.
yes To dollars, NoT JUsT To daMs AWA welcomes the money reserved in the recent NSW Budget to fund initiatives that secure urban water supplies and to droughtproof regional communities. Some key water investments in the NSW Budget include: • $700 million to maintain, renew and upgrade critical infrastructure across Sydney’s water network; • $39 million to upgrade and install town water and sewerage service; • $12 million to improve water and sewerage services for 61 Aboriginal communities in NSW; • $17 million to scope infrastructure projects in the Murray-Darling Basin that will further the State’s ability to meet water-saving requirements under the Basin Plan; • $1 million towards scoping and feasibility studies for the construction of a new dam on the Belubula River;
AWA hopes to work with the NSW Government as they decide where best the investment is spent in an effort to ensure NSW’s ongoing economic prosperity.
sMall WaTer aNd WasTeWaTer sysTeMs NaTIoNal coNFereNce 2014 The Small Water and Wastewater Systems National Conference will take place in Newcastle from 13–15 August. Don’t miss this event for industry personnel, with a three-day program featuring leading experts and peer sharing of great practice; great networking opportunities including the conference dinner; and a trade table exhibition showcasing the latest products and services for the SWWS industry.
Field • Laboratory • Process
Automatic Titrators
• Chlorine • Turbidity
Instruments for up to 40 Other Parameters
For more information call 03 9769 0666 Fax: 03 9769 0699
Email: sales@hannainst.com.au
water august 2014
• pH • DO • EC • Turbidity
Chlorine Analysers
Web: www.hannainst.com.au & www.hannachecker.com.au
pH/ORP/EC Controllers & Probes
25
awa News This year’s theme, Decentralised Water and Wastewater Systems: Advances in Technology and Recycling, will explore the re-emergence of decentralised water systems as a long-term solution to water scarcity. Conference attendees will also learn about the constraints associated with the centralised approach. To register and see the program please visit awa.asn.au/swws2014
braNch NeWs
a discussion from Gladstone Regional Council on the water and sewerage servicing strategy for Curtis Island. Many thanks must go to the host, Phil Boschoff from Gladstone Regional Council and his team. Thanks also to the team at Qld Water Directorate for the continued cooperation in running joint regional events and their efforts for this event in particular. Thanks also to TRILITY who provided lunch on the ‘cruise tour’.
Tributes flow for Julie’s top water award Moranbah’s Julie Smith has taken out a prominent
aUsTralIaN caPITal TerrITory
water industry award –
ACT Water Leaders Dinner
her as Queensland’s best
Don’t miss the annual ACT Water Leaders Dinner, which is scheduled for Thursday, 4 September 2014 at the Crowne Plaza, Canberra. This dinner is crafted for ACT business, industry and community leaders to inspire discussion, encourage networking and tantalise the
a top honour recognising water plant operator in 2014. Diagnosed with breast cancer in late April
tastebuds. Email actbranch@awa.asn.au for more information.
and having undergone
NeW soUTh Wales
unable to attend the AWA
NSW Northern Regional Conference
ceremony in Brisbane in
a mastectomy, Julie was Queensland Water Award June. However, stepping
Registrations are now open for the NSW Northern Regional
in to accept the award
Conference, which will take place 9–10 October in Tamworth.
on Julie’s behalf was her
This event will consist of a one-day conference and will include
supervisor, Isaac Regional Council (IRC) Team Leader Water and
local tours, a Gala Dinner and an optional workshop. The program
Sewerage West, Dwayne Lazar, who nominated Julie for the award.
will open with a panel discussion on implementing water quality management with dedicated sessions focusing on catchment management, emergency management and training to follow. Please visit the AWA website for the conference program and registration details.
QUeeNslaNd AWA Central Queensland Technical Seminar AWA hosted a technical seminar in Gladstone in June to complement Qld Water Directorate’s Central Queensland Mini Conference. Delegates were treated to three excellent presentations which drew out relevant aspects for Central Queensland: • Water Infrastructure: Contingency Planning for Flood Emergencies, presented by Dr Haydn Betts from KBR; • Upgrade of the Glenmore High Lift Water Pump Station, presented by Dr Jason Plumb from Fitzroy River Water; • Mt Isa Sewerage Upgrades, presented by Peter Baker and Mark Thomas from Harrison Grierson.
“I really wish Julie could have been there,” Dwayne said. “She came out on top of a tough field of statewide nominees and finalists and is among less than 10 per cent of women in the industry.” Julie said she was grateful for her nomination and thrilled to have won. Julie has worked for the Council for 26 years – with the past 23 spent at the water plant. A typical day for her and work colleague, Shelley Cottam, involves the recording of plant logs, water sampling and monitoring, checking equipment, chemical vats, fluoride levels and overnight water usage – then any machinery and ground maintenance needed. “I love it,” Julie said. “Responsible for the entire operation, we do all our own testing, monitoring and maintenance – which makes it more interesting, it’s a thinking job.” Isaac Regional Council (IRC) Mayor Anne Baker said Julie’s award spoke volumes of her ability. “Julie is a long-term, highly skilled and respected worker at Council, we are so proud of her and wish her a fast recovery.” Julie will receive a perpetual trophy for 12 months as well as
Gladstone Regional Council also organised a “site tour” for
a personal trophy and a trip to join the Water Industry Operators’
delegates, which consisted of a harbour tour viewing a number
Association (WIOA) delegation on a tour of water and wastewater
of the important and impressive projects going on in and around Gladstone. This culminated with a “sail past” of the three LNG plant sites under construction on Curtis Island, which are an awe-inspiring sight from close up. The context for water professionals was set by
facilities in New Zealand, as well as attending the Water Industry Operations Group NZ conference in May 2015. At the award ceremony, WIOA also pledged a $1,000 donation to Breast Cancer Australia.
august 2014 water
26
awa News
NeW MeMbers AWA welcomes the following new members since the most recent issue of Water Journal
NeW corPoraTe MeMbers
NeW INdIVIdUal MeMbers
OVERsEas
ACT D Hicks, R Signor NSW B Spannagle, B Dunn, D Albertson, G
PAX Water Technologies
Reardon, H Torkaman, L Withers, R Tang, R De Villiers, S Rudram, S Payyappat, S Owens, M Baker, U Vats QUEENSLAND D Saw, D Salazar, G Finlay, H Ballinger, J Rohdmann, J Walker, K Milligan, M Driver, P Driscoll, P Viljoen, R Burgess, S Casey, H Shaw, T Balasuriya SOUTH AUSTRALIA A Wilkins, B Murphy TASMANIA A Rieper, T Conacher VICTORIA A Arthur, C Macmeikan, C Rees, D Wiseman, D Oswald, F Noble,
NsW Corporate Silver Atlas Engineering
Corporate Bronze Mullaly Engineering Pty Ltd
VICtORIa Corporate Bronze Greenco Water Pty Ltd Waterdos Australasia
J Hicks, K Phogat, L Dainton Smith, M Polychronopoulos, M Prior, P Boundy, R Wood, T Walter, C Murphy, J Mallis, S Roberts WESTERN AUSTRALIA C Dube, D Richards, P Hall, S McCallum, T Rothnie
NeW oVerseas MeMbers L Kaiserman, United States
NeW sTUdeNT MeMbers NSW R Jenkins, Z Kang QLD A Gupta
aWa eVeNTs caleNdar This list is correct at the time of printing. For up-to-date listings and booking information please check the AWA online events calendar at: www.awa.asn.au/events
august Tue, 19 Aug 2014
townsville – Major Infrastructure Delivery – DVD screening – technical Event, Townsville, QLD
Wed, 20 Aug 2014
sa Young Water Professionals – Mentoring Event, Adelaide, SA
Thu, 21 Aug 2014
Implementing WaterQ: Launching the Minister’s Expert Panel, Brisbane, QLD
Tue, 26 Aug 2014
VIC seminar – the Victorian Water Company in 2030, Melbourne CBD, VIC
Tue, 26 Aug 2014
Wa technical Event: asset Management – Renewal Decision Making, Water Corporation, Leederville, WA
Wed, 27 Aug 2014
QLD – seqwater’s D&C Contract for Fluoride Dosing Facilities – a Brush With Relationship Contracting – Monthly technical Meeting, Brisbane, QLD
Thu, 28 Aug 2014
‘Where the Waters Meet’ – aWa tas annual Conference, Wrest Point, TAS
september Thu, 04 Sep 2014
aCt Water Leaders Dinner 2014, Crowne Plaza, Canberra, ACT
Thu, 11 Sep 2014
VIC YWP seminar – Paradigm shift, Young & Jacksons, Melbourne, VIC
Thu, 11 Sep 2014 – Fri, 12 Sep 2014
Master Class: understanding groundwater Law, Acton, Canberra, ACT
Fri, 12 Sep 2014
sa technical tour: an Insight Into sa Manufacturing Plants, Adelaide, SA
Fri, 12 Sep 2014
QLD gala Dinner & awards Night, Brisbane, QLD
Tue, 16 Sep 2014
Vic seminar – Water solutions for Emerging Nations, Melbourne CBD, VIC
Tue, 16 Sep 2014
Wa technical Event: Mundaring WtP a PPP success, Water Corporation, Leederville, WA
Wed, 17 Sep 2014 – Fri, 19 Sep 2014
ENVIRO’14, Adelaide Convention Centre, SA
october Wed, 8 Oct 2014
sa Young Water Professionals Event, Adelaide, SA
Wed, 8 Oct 2014
QLD Monthly technical Meeting, Brisbane, QLD
Thu, 09 Oct 2014 – Fri, 10 Oct 2014
NsW Northern Regional Conference, Quality Hotel Powerhouse, Tamworth, NSW
Fri, 10 Oct 2014
sa awards – Judging Day, SA Water House, SA
Tue, 14 Oct 2014 – Wed, 15 Oct 2014
National Water Policy summit, Shangri La, Sydney, NSW
Wed, 22 Oct 2014
sa technical seminar: Integrated urban Water Management – social, Economic, technical and Political aspects, Adelaide CBD, SA
Thur, 23 Oct 2014
Wa National Water Week Conference, Parmelia Hilton Hotel, Perth, WA
Fri, 24 Sep 2014
Nt Branch Conference: Water In the Bush, Darwin Convention Centre, NT
Tue, 28 Oct 2014 – Thu, 30 Oct 2014
National Operators Conference 2014, Cairns Convention Centre, QLD
water august 2014
27
Interview
LET’S TALK ABOUT WATER MWH Global’s UK-based director of global strategy, David Smith, recently spent a week in Australia meeting heads of the water sector to discuss the challenges the industry faces in Australia. In this interview, he talks about the synergies between the two countries and offers insights into issues such as operational efficiency, customer education and global water information sharing.
How similar are the water issues australia faces to those of the uK? and what do you see as the main differences? Of course there are differences in terms of population size and distribution and climate, but the issues are fundamentally the same. Population growth, resilience of services to climate change events, long-term sustainability and ageing infrastructure all have to be dealt with, while at the same time keeping customer bills affordable. The main difference is water utility ownership approach. In 1989 the UK moved on the privatisation of the water industry in England and Wales and this has driven huge developments in terms of asset management and efficiency. Fundamentally it is not about privatisation; it is about an approach to water services and some of this experience is very relevant to Australia. In contrast, some of the customer approaches adopted in Australia, to some extent driven by the previous drought situation, are world-leading and highly transferrable to the UK.
What do you see as the biggest issue facing the australian water industry? Two words: operational efficiency. If water companies aren’t seen to be efficient and effective, they won’t be in business. It’s as simple as that.
In the current urban water sector, with the 10-year drought behind you and water storage now up around 70% in capital cities, the focus is now on maintenance and operating expenses rather than major capital expenses. Shareholders (state governments) want more return on investment – rates cannot be put up too much, so business needs to get smarter at maintenance and operating expenses. In the UK we have had a big push for many years now to drive operational efficiencies through better asset management and operating regimes. There are learnings Australia can benefit from out of the UK because our water industry regulatory model was established in 1989, whereas in Australia corporatisation happened in the mid-90s, so we are a few years ahead of you … and we didn’t have a decade-long drought to contend with! I came to Australia three years ago to talk about this very issue, but the industry was still in delivery mode and not quite ready to hear it. Now project delivery isn’t as urgent on the agenda and companies are realising they need to do more for less on expenditure. Expenditure in Australia will still be in the billions of dollars, but that is down from the tens of billions spent on issues brought on by drought. Today’s spend will be on rehabilitating or maintaining existing assets and finding clever ways of using data and analytics to improve operating efficiency.
Retro-fit of real time monitoring and control systems at wastewater treatment works in the uK resulted in 30% saving in energy costs, 20% saving in chemical costs, and increased robustness and service levels while avoiding expensive additional capital investment. august 2014 water
28
Interview
an integrated urban design and development approach can achieve significant capital and operating cost savings by naturally attenuating flooding before it gets to pipes and treatment works, as demonstrated by this swale in upton in the uK.
“In the UK, we are now pUttIng the cUstomer at the centre of Investment decIsIons as they gIve theIr opInIon on levels of Investment and servIce versUs the cost ImplIcatIon on water bIlls” You are a keen advocate of water companies “putting the customer at the centre of every decision” they make, right down to every dollar they spend. Why is this so crucial for the industry and what percentage of water companies do you think actually do this? Yes, I am [a keen advocate]. Each customer is important to business, any business. In the UK, we are now putting the customer at the centre of investment decisions as they give their opinion on levels of investment and service versus the cost implication on water bills. As part of our next five-year asset management plan period, AMP6, it is mandatory that any corporate plan must be endorsed by a customer consultative committee (to the regulatory authority). This approach requires a significant change in behaviours across the industry to truly put the customer at the centre. In Australia, while you have been more proactive with the customer, water companies currently “advise” customers what they are doing; they don’t actually seek endorsement. Perhaps there is a case for mandatory customer endorsement here as well – it would certainly ensure that customers are at the very centre of every decision taken.
water august 2014
Do you think australian water companies have educated customers to the right level? I think there’s room for improvement. In Australia it costs approximately $1.20 for 1,000 litres of water out of the tap, yet as in many other western countries people still happily fork out double that amount for only 500ml in a plastic bottle. I would say it doesn’t make sense, but it does when you realise that the majority of the Australian population doesn’t know this. They need to be informed and educated. Recycled water is another issue. Technology has moved on and water can be recycled to the highest standards for a relatively low cost. Right now is the time to educate people about the benefits of recycled water – that it can and should be used as many times as possible before you send it for treatment and discharge to rivers and the sea. Now is the time to do this – while the drought is over; because it will return and it will be a lot easier to convince a population to implement certain measures if they are already apprised of their benefits.
What changes do you believe need to be made in the global water industry? Without a doubt, we need to become better at information sharing. This is the reason I came to Australia – to share expertise. The more information we share, the greater the benefits we reap. By ‘benefits’, I mean improvements to the industry as a whole. Australia is a leader in many aspects of urban water, especially integrated water cycle management. In a lot of respects, rural Australia is further ahead for drought management than most cities worldwide. Australian water companies need to be sharing their experience of this most recent drought – the issues they faced, how they overcame them, what measures they have put in place for when the next drought hits because, let’s face it, there will be another one at some point.
29 CARRY MORE Interview WATER METHODS WITH YOU WHEREVER YOU NEED THEM MOST. as a partner in a JV, MWH delivered a £700 million program for southern Water in the uK, designing a wastewater plant to take maximum advantage of potential for energy generation from biogas from digesters and generation of electricity via onsite CHP units.
You have talked about capital maintenance being a global issue. In your opinion, what is the “right” level of capital maintenance? That’s a complex issue and gets back to data management and having good strategic asset management systems that enable sound investment and decision making. Having the right level of investment in capital maintenance depends on the collection and management of data to enable optimum capital maintenance investment decisions. The right level will vary from authority to authority and depends on the age, conditions, deterioration rates and type of assets, as well as asset criticality and understanding of the risk and consequence of failure. There has been some really great work in the UK and elsewhere on developing new approaches and tools to help us really hone in on the right level of capital maintenance.
the water industry in the uK has begun to move from “new build” to “no build” solutions. How have you found the adoption of this approach in australia? This approach is relatively new to Australia because the focus over the last 10 years has been on the design and delivery of major capital works. The idea of deriving solutions that results in something you don’t build, or “sweating the asset”, is a new concept here, whereas it has been the case in the UK for a few years now. For instance, it is not uncommon to find ways to increase the headroom at a treatment works and ‘patch up’ the existing assets to avoid the need for building a new lane or stage at a treatment works, all while maintaining the level of service to customers. This “no build” approach will become more prevalent in Australia and elsewhere as we push for greater value for money. wJ
aboUt mwh global MWH Global specialises in strategic consulting, technical engineering, environmental and construction services focusing
The DR 1900 Portable Spectrophotometer features over 220 of the most commonly tested water methods.
on water and natural resources for built infrastructure and the environment. MWH is a leader in the field of water asset management in the UK, having been awarded 11 of 14 recent water asset management contracts in the country. David Smith
1300 887 735 | hachpacific.com.au
is the company’s UK-based director of global strategy with particular expertise on how to get better value for money from water assets and achieve operational efficiencies.
august 2014 water
30
Feature Article
HOW PUSHING WATER UPHILL CAN SOLVE OUR RENEWABLE ENERGY ISSUES How to provide the energy storage Australia needs to fully embrace renewables? Andrew Blakers from ANU and co-author Roger Fulton from Jacobs/SKM, present a simple, and inexpensive, technique.
M
ore and more renewable energy sources are being plugged into Australia’s electricity grids. South Australia, for example, will get 40 per cent of its electricity from wind and solar once the Snowtown wind farm is completed later this year.
Of the available electricity storage options, such as batteries and flywheels, pumped hydro is by far the cheapest. It has no standby losses while the water waits in the reservoir, and can reach full power in 30 seconds.
But if renewable energy is ultimately to dominate the market, we will need ways to store the energy so we can use it round the clock. The good news is that it is easy to store energy. All you need is two small reservoirs – one high, one low – and a way to pump water between them.
There is little opportunity for Australia to develop on-river hydroelectric power, because of environmental and other constraints. But, there are vast opportunities for short-term offriver energy storage. A typical site would comprise a pair of small reservoirs connected by a pipe through which water would be cycled daily, together with a pump and turbine, powerhouse and power lines.
This technique, called “off-river pumped hydro energy storage”, can potentially provide the energy storage that Australia needs to embrace renewables fully. It’s cheap, too.
HOW PUMPED HYDRO WORKS When there is excess electricity, water is pumped through a pipe or tunnel to the upper reservoir. The energy is later recovered by letting the water flow back down again, through a turbine that converts it back into electricity. Efficiencies of 90 per cent in each direction are possible. Pumped hydro is by far the most widely used form of energy storage, representing 99 per cent of the total. Worldwide, pumped hydro storage can deliver about 150 gigawatts, mostly integrated with hydroelectric power stations on rivers.
TIME TO GO OFF-RIVER
Australia has thousands of excellent potential sites in hilly areas outside conservation reserves, with typical elevation differences of 750m. They don’t need to be near a wind or solar farm. Off-river electricity storage has several advantages over typical on-river facilities: • There are vastly more potential sites; • Sites can be selected that do not clash with environmental and other values; • The upper reservoir can be placed on top of a hill rather than in a valley, allowing the elevation difference to be maximised.
In an “off-river” system the same water circulates in a closed loop between the upper and lower reservoirs, eliminating the need for the facility to be built on a river. The amount of energy stored is proportional both to the elevation difference between the upper and lower reservoirs (typically between 100m and 1000m), and to the volume of water stored in the upper reservoir. Electricity storage systems need to be able to deliver instant power output for periods of a few hours. This covers short-term fluctuations in wind and solar outputs, peaks in consumer demand (such as very hot summer afternoons), and unplanned outages of generation and transmission infrastructure. Using stored energy also helps to keep power lines from wind and solar facilities in use for more of the time.
WATER AUGUST 2014
Tumut pond reservoir in the Upper Tooma river for power generation in the Tumut valley in the Snowy Mountains of New South Wales.
31
Feature Article No provision needs to be made for floods (typically a major cost). A system comprising twin 10-hectare reservoirs, each 30m deep with a 750m elevation difference, can deliver about 1,000 megawatts for five hours. Between 20 and 40 of these systems would be enough to stabilise a 100% renewable Australian electricity system.
HOW MUCH DOES IT COST? As the reservoirs are tiny (just a few hectares) compared with typical hydro reservoirs, they are a minor component of the cost. Most of the cost is in the power components (pipes, pumps, turbines, transformers and transmission). Initial estimates suggest that the cost of an off-river system at a good site is around A$1,000 per kilowatt of installed capacity. Here is a hypothetical case study. A 200-megawatt solar power facility delivers a maximum of half of its power output to the grid in real time, and stores the rest for the evening. Now, instead of peaking at the sunniest time of day, the solar power output extends from 8am to 10pm (depending on season and cloud cover), with a maximum power output to the grid and the pump each being 90 megawatts (after allowing for losses). The reservoir can be recharged at night using wind energy to cover the morning demand peak. The stand-alone costs of the solar power system and the shortterm hydro storage system are A$2,000 and A$1,000 per kilowatt, respectively. After accounting for storage losses balanced by savings from sharing of the transformer and transmission costs between the two systems, and the fact that the hydro storage rating is half that of the PV system, that puts the total system cost at about A$2500 per kilowatt.
In other words, using pumped hydro storage to smooth out the peaks in output from a solar power station only adds an extra 25 per cent to the cost. That’s much cheaper than using batteries.
LOCATION, LOCATION, LOCATION Spend some time with a map or Google Earth and you can spot dozens of excellent potential sites, in hilly farmland or along existing powerline routes. Australia has thousands of candidate sites throughout most inhabited parts of the country. For example, the Tumut 3 hydroelectric station has Australia’s largest pumped hydro storage capacity (1500 megawatts), an elevation difference of 151m, and a substantial lake that must cope with major floods. But a small off-river system could be built nearby, comprising twin 13-hectare reservoirs with an altitude difference of 700m, connected by a 5km pipe traversing a powerline route. This system would store enough water to deliver 1,500 megawatts for three hours, and would cost much less. WJ
THE AUTHORS Andrew Blakers is Director of the Centre for Sustainable Energy Systems (CSES) at Australian National University. The article was co-authored by Roger Fulton from Jacobs/ SKM, who has worked in the hydroelectric industry since 1975 as an engineer and project manager. The article has been reprinted courtesy of The Conversation (theconversation.com/ how-pushing-water-uphill-can-solve-our-renewable-energyissues-28196)
GF Piping Systems
iJOINT - compression fittings
The Smarter Fitting Applications
Water Distribution Lines House connections and service lines Pressure Sewage | Industrial Applications Mining Industry | Leisure Parks Golf Courses | Camping grounds | Farming Green-houses | High-end Irrigation | Compressed Air
Contact Us:
t: 02 9502 8000 or 1300 130 149 f: 02 9502 8090 australia.ps@georgfischer.com www.georgfischer.com.au AUGUST 2014 WATER
32
Feature article
Queensland YWPs: uP for a Great Cause When the Queensland AWA Branch was approached to give a waterrelated presentation to students from a detention centre, they didn’t know quite what to expect. Abraham Negaresh takes up the tale.
R
ecently the AWA Queensland Branch was approached by Mr Tony Oliver, Science Coordinator for the Brisbane Youth Education and Training Centre (BYETC), to give a presentation to their students. The request was forwarded to the Young Water Professionals (YWP) committee to follow up and Research and Education Coordinator, Abraham Negaresh, took charge of the task. During initial conversations with Tony, BYETC – and its very important work – was explained in greater detail. BYETC has the responsibility to educate and train students, ranging from 10 to 17 years of age, who are on remand or serving custodial sentences at the Brisbane Youth Detention Centre. One of the courses offered by the centre – and the one in particular that the YWP were invited to assist with – is Certificate II in Water Operations (Catchment Management). The YWP were asked if they could attend one of the Certificate II classes to provide a short presentation and carry out a practical exercise for the students. With the support of their respective
organisations, a number of the YWP committee were able to set up a team for this event. The team consisted of Justin Simonis, Robert Goedecke, Ehsan Eftekhari and Abraham Negaresh. Wanting to demonstrate the importance and impact of financial wellbeing on a country’s capacity to supply clean drinking water, the team adapted an activity that they had seen before to create a ‘clean water challenge’ for the students.
An eventful dAy Because none of the team members had led this activity before – and none of us had previously been to a detention centre – there was a certain air of expectation among the group on the morning of the visit. All of us were curious as to what we were going to see and how the day would pan out. After passing through security, we were directed to the training centre office for brief introductions before heading to the laboratory where we would meet the students and conduct the activity. On our way to the lab, we were given a short tour of the detention centre; it was pleasing to note the open green spaces and even a small openair auditorium. When we got to the laboratory, we met the 11 students (aged between 13 and 16) who would be participating in the activity. The students were from a mix of different courses including Junior Secondary Science, Access 10 (Science) and Certificate II in Water Operations (Catchment Management). Prior to commencing the practical activity, we were each invited to give the students a quick overview of our professional experience in the water industry, which by chance covered a good range of professions in the industry from government roles in planning, to research, consultancy and construction.
In front of the Brisbane Youth Detention Centre. From left to right: Ehsan Eftekhari, Robert Goedecke, Abraham Negaresh and Justin Simonis.
water AuGuST 2014
In the laboratory at the Brisbane Youth Detention Centre. From left to right: Justin Simonis, Robert Goedecke, Abraham Negaresh, Ehsan Eftekhari and Tony Oliver.
33
Feature article
Treating “raw” water using the treatment systems prepared by the students. Finally it was time for us to start the practical activity, with a short presentation about water scarcity and the relationship between the availability of treated water and the economic circumstances of different countries around the world. Following this, the students were divided into four groups of three. Each group represented a country and, depending on the financial wellbeing of that country, a budget was allocated to them to spend on their water treatment system. With our help the students worked within the financial constraints of their country to set up a simple water treatment system by purchasing different materials such as gravel, sand, cotton and so on. Countries with larger budgets could afford a higher degree of treatment, while those with smaller budgets had fewer steps in their treatment process. After they all made their treatment systems a volume of “raw” water was provided to treat One of the treatment systems that using their system. were prepared by the students.
The task clearly engaged the students as they eagerly awaited the outcomes of the water treatment experiment and they were all surprised to see the differences in the treated water quality.
A successful exeRcise While this activity was mainly intended to be a fun, teamwork exercise for the students, the fact that each group had a limited budget made them work to get the best for their money. Most importantly though, it demonstrated to the students how lucky we all are to live in Australia where treated water is so readily available that most of the time we take it for granted, as opposed to those countries in the world that are not so fortunate. Working with these young students and seeing their passion and excitement in doing the activity was a great experience for the group. We all agreed that there was a lot of talent among the students and that BYETC is doing a great job in motivating these young people to get back into society. Finally, we would like to thank Tony Oliver and the other teachers at BYETC who gave us the opportunity to have such an unforgettable experience, the YWP Queensland committee and Sharon Ible, AWA Queensland Branch Manager, for their support. WJ
the AuthoR Dr Abraham Negaresh (email: abraham. negaresh@mwhglobal.com) is a Process Engineer at MWH. He has been an active member of the Queensland Young Water Professionals committee for more than two years. Abraham is currently the Research and Education Coordinator at YWP.
AuGuST 2014 water
34
Opinion
Trade WasTe regulaTion and Pricing for uTiliTies Infrastructure Australia has identified AUD37.5 billion of water utility assets for sale, to generate funds to tackle a growing infrastructure deficit, says Envirofriendly’s Neil Christie. They also argue for a national water regulator. Many in the industry feel this would promote more efficient regulation and opportunities for investment. In February 1994 the Council of Australian Governments (COAG) adopted a strategic water reform framework, which they incorporated into the National Competition Policy agreements. COAG envisaged that the framework would be implemented by 2001. It is now 20 years on and domestic users have experienced substantial increases in water costs despite significantly reducing consumption. In 2004, after slow to intermittent progress, the Premiers signed the National Water Initiative (NWI), which obliged State and Territory governments to set prices based on full cost recovery and consumption-based pricing principles to ensure adequate provision for infrastructure investment and encourage efficient water use. Using pricing to promote economic efficiency is a fundamental tenet of National Competition Policy, the COAG Agreement and the NWI. Competitive markets are desirable because the price signals they generate ensure that resources are allocated to the use in which their value is greatest. The NWI was described as “Australia’s enduring blueprint for water reform’, leading to greater water productivity and greater certainty for investment”. When fully implemented, all dischargers would pay for the transport of wastewater to treatment plants and the cost of treatment to the basic level accepted by customers of recycled water (less any recoupment of costs from sale of biofuels and the like). Recycled water could then be provided to customers for the cost of storage and transport. Customers requiring higher levels of treatment would have that additional cost included in their recycled water charges. The regulatory framework comes under notice at this time as Infrastructure Australia (IA) has identified AUD37.5 billion of water utility assets
WATER august 2014
for sale, to generate the funds needed to tackle the country’s growing infrastructure deficit. IA put forward a strong argument for a national water regulator. Many senior industry representatives support this view and feel that this would promote more efficient regulation, opportunities for private investment, a corporatisation model and greater certainty for customers.
Public infrastructure Privatisation Privatisation of public infrastructure is advocated on the grounds that government policymakers are inherently reluctant to implement efficient pricing and investment. This is the natural domain of privately run enterprises subject to competitive market forces. User charging is also an effective way in which governments can create opportunities for increased private sector investment in infrastructure, because it leads to revenue streams that yield better economic and environmental outcomes. Our infrastructure-oriented Prime Minister has recognised that more must be done to better harness the potential for private sector investment and lift Australia’s falling productivity. Australia’s superannuation funds are currently crying out for opportunities to invest in nation-building infrastructure. Governments are keen to tap into these funds to reduce the need for massive public investment. This will only be achievable if project sponsors are able to offer a risk-return profile that is more closely matched to the expectations of superannuation funds. The key is that the right regulatory framework be set up in order to allow private sector efficiency and innovation to translate into tangible benefits for water customers, while also allowing private sector infrastructure owners to make fair returns on their investment.
35
Opinion Infrastructure includes the systems used for the collection and treatment of wastewater. This article focuses on trade waste, in particular commercial customers such as Food Service Establishments (FSEs), which have a major role to play in limiting the costs of sewage treatment and producing recycled water. Reducing the volume and strength of trade waste can also save energy. Historically, trade waste costs have been ignored due to the relatively low costs for collection and disposal. For Sydney’s major commercial dischargers, trade waste costs amount to a mere 4.5% of the total water and sewage account. Industrial customers also discharge trade waste, but are not our focus here.
Different aPProaches Regulatory practices differ from state to state and tend to be a reflection of political imperatives rather than economic rationalism. Independent bodies proudly herald how they are reducing “cost recovery through prices”, while emphasising the importance of “water retailers ensuring customers experiencing hardship receive assistance and are treated fairly”. Pricing must encourage economic efficiency in service delivery, investment and water use. For a business to continue operating in the long run, prices need to be sufficient to generate enough revenue to enable both capital and operating costs to be recovered. This includes an appropriate risk-weighted return on capital to investors and the interest payments on debt. Profit is based on the return required on capital and is effectively a set rate regardless of any savings in operating expenses. When the Weighted Average Cost of Capital (WACC) is set too low, revenue does not cover costs and there will not be the incentives for utilities to undertake efficient investment in either upgrading or augmenting infrastructure. This also encourages excess consumption, which places pressure on existing capacity and increases the need for additional capital for infrastructure. If the WACC is too high, firms will have incentives to bring investment forward as early as can be justified and may over-invest or gold-plate. Most water utilities have not been set up correctly, in an accounting sense. In the absence of regulatory accounts they have been unable to identify operating costs and applied a ‘cost down’ system after determining the total revenue required. Despite bulk water purchase experiencing far and away the biggest increase in Cost of Sales and Expenses, the revenue percentage of 53.4% in 2008 for water was still 54.8% in 2013 (Sydney Water Annual Reports 2007–08; 2012–13). While a ‘bottom-up’ approach, which would identify the actual costs of providing each service, is a challenging exercise it is also difficult to see how a business can be effectively managed without such a methodology. Volume-based charging is of benefit with water usage, as it serves to signal to users the cost that an additional unit of consumption imposes on the supply system, whereas load-based pricing, for trade waste, reflects the cost drivers of treatment, disposal and management. It signals to customers the costs of discharging to the wastewater system and can provide incentives for them to find the least-cost way to manage trade waste, including the possibility of investing in on-site treatment. In their Interim Price Monitoring Submission to the Queensland Competition Authority, Unitywater suggests that there is a law of diminishing returns that applies to sewage treatment plants (STPs) augmentation and the current practice of upgrading existing plants may be the most expensive option. Investing in potential alternative nutrient or pollutant reduction initiatives may achieve greater economic efficiency and be environmentally beneficial.
oPeninG a can of worms It may well be more cost-effective for industry to modify their practices. Businesses recognise that a greater emphasis on reducing trade waste loads would facilitate recycling, but are inclined to wait for economic incentives or financial support from government. One liquid waste management consultant expressed the view: “It’s a big, complex can of worms… and you show me any restaurant, any foodservice establishment, any high-strength waste-generating facility, that voluntarily wants to get into a program to manage this stuff.” All states and their regulators say that the charge for trade waste is determined by: • The volume of effluent discharged; • The level of sewage treatment applied; • The strength of effluent discharged. Water authorities say that they continue to develop efficient trade waste prices with the aim of encouraging the most costeffective methods of treating trade wastes, whether at source or downstream. Charges include non-compliance excess trade waste charges in order to provide the necessary incentives for dischargers to consistently comply with their conditions of approval. The primary reason why the current waste disposal facilities are gravely deficient is that they are priced in ways that do not reflect economic costs. In Sydney in 2007/08 sewage charges were $1.34 per kL. By 2013/14, Sydney Water realised that only 65% of its trade waste costs were recouped through these charges. It has addressed this and commercial premises now pay an average of $2.69 per kL (household fees at an equivalent $2.05/kL) for the additional cost of pumping, network maintenance, chemical dosing, corrosion and odour. It should be noted that large dischargers with effective pretreatment programs are charged less and, to date, an efficient, low-cost way of measuring contaminants such as Suspended Solids, Biological Oxygen Demand and Fats, Oils and Grease is not readily available. Over the last 10 years Sydney Water’s ‘Every Drop Counts’ Business Program saved more than 65ML/day of drinking water by working closely with its business customers.
founDeD on waste The restaurant is an institution founded on waste and relies heavily on Best Management Practices in kitchens and grease interceptors, which are normally highly efficient but have an optimum operating temperature of between 24 and 30 degrees. Modern oils, high temperatures, surfactants, surge flows, density currents and short circuiting can produce a shortening of the detention time in a grease trap and a reduction in its solids removal efficiency. Sewers are adversely affected by excess FOG (fats, oils and grease) requiring excessive cleaning of lift stations, premature pipe replacement, increased sewer gases and loadings at STPs. The National Wastewater Source Management Guidelines authorise local water utilities to assume compliance for commercial customers with grease traps. “By following the guidelines, utilities can: • Improve sewage system performance, including reduced frequency of sewer chokes and odour complaints; • Provide financial incentives to business and industry for cleaner production and waste minimisation.” So the pricing regulations are not really set out to specifically prevent or control discharge of FOG to the sewer.
august 2014 WATER
36
Opinion Sydney Water’s costs of pollution are: fats, oils and grease (43.2%), Biochemical Oxygen Demand (43.2%), and the temperature of water being in excess of 25 degrees (13.6%). Testing by Envirofriendly has shown that, with modern dishwashers, businesses such as
table 1. Price to receive and discharge a kilolitre of water in Australia City
Residential
Commercial Restaurant
restaurants, nightclubs, hospitals and convention centres rarely
Adelaide
$5.89
$3.95
discharge effluent below 35 degrees and, in actuality, above 40
Brisbane
$6.76
$7.75
degrees most of the time on a Friday and Saturday. FOG and BOD
Canberra
$5.68
$6.36
would regularly exceed 1,000 mg/L. Sydney Water considers each
Gold Coast
$8.49
$6.16
Hobart
$5.22
$3.97
Logan
$8.72
$6.67
Melbourne
$6.55
$5.36
Sunshine Coast
$7.21
$6.39
Sydney
$5.76
$5.00
restaurant to use an average of 3.4 kilolitres of water a year. Fast food shops use an average of 2.7 kilolitres of water a year. The Essential Services Commission (ESC) in Victoria in June 2009 considered water construction costs would increase in line with the CPI and there would be no real increase in prices. The Government’s expectation was that water bills would no more than double over the regulatory period (average 14.9% pa). Despite water consumption being down 11%, from 2008 to 2012, the average annual increases in revenue from services were: volume charges for sewage – 14.2%; service charges for water – 16.3%; trade waste charges – 19%; volume charges for water – 20.3%; and service charges for sewage – 21.7% (City West Water’s Annual Reports 2007/08 to 2012/13). Bulk water charges were driving 77% of the opex increase, but rises were applied across all the services provided. While cushioning the impact on voters in residential households, subsidising does not reduce business costs. When a user charge exceeds the relevant cost and the charge cannot be avoided, the excess is in effect a tax.
timidity (see Table 1). The taxpayers’ costs for infrastructure repairs from restaurant grease are an extreme financial burden on every city. Hundreds of millions of dollars are spent annually on sanitary sewer repairs, lift station repairs, and raw sewage overflows caused by grease blockages. These costs are unnecessary and controllable. Despite all the claims to be pushing through the agenda of the NWI, the author cannot help but recall one water business’ literature that stated: “Of course we will encourage the debate (on stopping pollution at source) but we believe that we will be developing additional treatment processes at our works. This is a key driver of capital investment and profits to our shareholders flow from return on capital:
The user-pays principle means that recipients should pay for the
• investment for improved sewage treatment;
services that they benefit from.
• invested to achieve further reductions in numbers of pollution incidents; and
robust comPliance ProGram vieweD as unnecessarY A user pays cost recovery system is purportedly being introduced gradually in most jurisdictions. In Canberra: “ACTEW anticipates that the three-year introduction period will be enough time for customers to avoid strength-based charges and does not anticipate earning revenue from strength based charges in the future”. The author found that the view held by regulators was that FSEs were taking every possible step to minimise contaminants discharged in effluent from their premises and a robust compliance program was unnecessary. On the contrary, they considered it necessary to simplify the charges for commercial customers, as they “have little control over the quality of their trade waste exiting the pre-treatment equipment and have limited options to improve the quality of their trade waste”. A team leader with ACTEW Water, Wayne Eccleston, has
• invested to achieve further reductions in sewer flooding.” The regulatory regime for the water industry since privatisation was to have played a major role in ensuring increased efficiency and service, and environmental improvements. The program is probably the most complex and challenging of the National Competition Policy commitments. If it is fully implemented, however, it will probably also be the most rewarding. The Productivity Commission has estimated that improving productivity and efficiency to achieve best practice in energy, transport, infrastructure and other activities could increase GDP by nearly two per cent. In the absence of a level regulatory playing field, asset privatisations in the Australian water sector are unlikely to be followed up with any tangible action. One potential model to achieve such consistency is for states to cede relevant powers to a new, single national water regulator.
found 300mm of fat caking the inside of six- to 14-metre wet wells stationed at height intervals in Canberra’s gravity-fed sewer
the author
system. White as lard and laced with sanitary wipes, the fat has to
Neil Christie (email: neil@envirofriendly. com.au) is Managing Director of Queensland company Envirofriendly Pty Ltd. Neil has been involved in the waste industry for more than 30 years, including the past 20 in biological waste management systems and solutions. He is an approved Water Efficiency Assessor and works in conjunction with Water Services Australia. He is also a member of AWA.
be shovelled out. Some wells are scraped out every six months. At Fyshwick, one is cleaned every four weeks. “A lot of people don’t care about the next person who comes along. They are getting worse, not better,” Mr Eccleston said. At a time when regulators need to be sending signals to FSEs about introducing measures at source, to minimise the strength of pollution and contaminants from their premises, there is at best
WATER august 2014
12 May - 14 May 2015 Adelaide Australia
CALL FOR PAPERS AustrALIA’s
LEADIng
IntErnAtIonAL “WAtEr For groWtH AnD prospErItY” Australia has many unique advantages including our world-class resources, proximity to Asia, a temperate climate and the distinct opportunity of growth industries including agribusiness, mining, and tourism. However, for all these industries to prosper they require one vital element – water. Safe water. Secure water. Sustainable water. Access to water. Many challenges lie ahead for the water sector in managing water in urban,
regional and rural contexts. We need water professionals and organisations to step-up and lead innovation, debate and provide technical know-how across the broad scope of water and wastewater management to ensure we harness these opportunities, both domestically and overseas.
WAtEr ConFErEnCE & ExHIbItIon
Ozwater’15 will once again, attract national and international speakers and delegates to attain a new wealth of industry knowledge and to cultivate strong and applicable ideas to ensure the longevity of our greatest resource. orgAnIsED & prEsEntED bY
ADELAIDE ConvEntIon CEntrE
www.ozwater.org
38
Conference report
Biosolids and source ManageMent specialist conference 2014 Diane Wiesner reports on the biennal Biosolids and Source Management Conference, which this year took place in Melbourne. The 2014 Conference for the Biosolids Specialist Network and Source Management Specialist Network was held in a very cold Melbourne on 25 and 26 June. In spite of the weather, the Conference was well attended with 148 delegates, including a contingent of New Zealanders representing both disciplines. Keynote speaker, Dr sudhir Murthy, Innovations Chief for the District of Columbia Water in the US, opened the meeting with a thoughtful presentation focused on some of the strategies being adopted there to maximise the biosolids quality and biogas yields from processing primary and secondary sludges, achieved by optimising anaerobic digestion processes. Water New Zealand Technical Co-ordinator, Nick Walmsley, followed with a relaxed presentation traversing a wide range of topics. Nick is principally concerned with the nature, diversity and source of contaminants that arrive at treatment plants in the land of the long white cloud. He raised the prospect of newer, more thoroughly researched regulation with the emphasis returning to health risks, as well as the more recent focus on risks to the environment. Marking a first for a specialty conference, five interactive and well-attended workshops featured throughout the program, ensuring the oral paper sessions were more ‘digestible’ for the audience, affording them an opportunity to be more actively involved in panel discussions and group work.
BiosoliDs Workshop 1: oDorous Emissions from BiosoliDs Richard stuetz and James Hayes from UNSW headed up a most interesting workshop, introduced by Nancy Penney from Water Corporation. The topic of odours is a constant and recurring source of concern for the industry, especially as urban encroachment continues to advance into former industrial zones where wastewater and biosolids treatment is generally located.
Day 1 Day 1 paper sessions primarily addressed technological challenges and solutions for biosolids processing and trade waste management. shannon uern presented Doug Richards’ paper Co-Digestion of High Strength Organic Substrates – Waste to Energy, essentially an operational overview of SA Water’s journey through co-digestion. The research began by looking at increased gas production associated with adding organic materials to the digester at Glenelg STP (a relatively small mesophilic digester). Although there was no shortage of sources for organic substrates to use, dairy and poultry wastes were readily available in decent quantities (snack food manufacture or retail greasy wastes were also available). Issues such as increased corrosion of plant, control over volumes of gas produced and treatment difficulties were identified. Pretreatment was found to improve digester performance, improve management of the process and enhance the quality of end product biosolids. Different organic substrates and method used depended on the chemistry of the available substrate. Much has been learned from this study on how best to use codigestion to improve biogas production in an anaerobic digester (important in efforts to reduce SA Water’s carbon footprint), reduce the volume of biosolids, optimal approaches to reducing the extent of corrosion in the sewer network from the presence of increased levels of organic materials, while adopting this practice to assist in reducing levels of organic waste going to landfill. Later in the day, in what became a complementary presentation, susan Kitching from Aurecon spoke about Optimising Anaerobic Digestion Performance in Sydney Water’s Program to Improve Biosolids Product Quality and Reducing Operating Costs. Essentially Kitching audited the performance of Sydney Water’s Malabar plant through, first, a performance review, followed by an operational and then a maintenance review. The goal was to identify how improvements could be made, whether newer, more technologically superior equipment might replace existing plant, and also how thorough and careful maintenance was being undertaken. Kitching made 51 recommendations, including advice to increase the temperature of the digester, and to increase SRT (sludge retention time) by incorporation of recuperative thickening. The results from accepting and implementing recommendations have reduced the volume of biosolids being produced from Malabar and increased the quantities of biogas produced.
Stuetz began by outlining work on odour analysis. He pointed James Hayes out that only a small number of chemical species appear to be directly responsible for odour annoyance. James Hayes addressed the issue of community engagement; that is, looking at how water utilities might be able to improve the understanding and tolerance of affected locals from periodic experiences of emissions from facilities or from transporting biosolids. The workshop concluded with different groups of delegates acting as odour testers to identify initially unidentified smells, with varied success.
water august 2014
Keynote speaker Dr sudhir Murthy from District of Columbia Water in the us and Nick Walmsley from Water New Zealand.
39
Conference report
BiosoliDs Workshop 2: BiosoliDs anD EnErgy opportunitiEs Acknowledging the wastewater treatment plant as a resource recovery centre has become recognised overseas (UK and US) and increasingly in Australia. This workshop, facilitated by Diane Wiesner, began by looking at the initiative being taken at Yarra Valley Water to focus on using its anaerobic digester to turn organic food wastes into biogas and biosolids. In 2011, the utility first looked at the opportunities for using STPs to produce renewable energy. Just over a year later, the design and construction of the plant began. The process begins with retrieval of the waste, pre-treatment and blending; then into the anaerobic digester, which yields biogas that is subsequently cleaned and stored for electricity generation. Davood Nattaghi followed with a UK perspective on biogas being used as a primary energy source for wastewater treatment. Aecom’s Bill Barber, a keynote speaker from a previous Biosolids Specialty Conference, followed by talking about the most recent work on energy yield that can be achieved from different stages of the wastewater treatment process. Primary treated sludge in an anaerobic digester was shown to yield more gas than secondary-treated sludge, which in turn was better than tertiary-treated sludges. Carbon content in the sludges at various stages was judged to be the critical determinant. A lively open discussion then followed, framed around a series of questions and issues raised by the presentations. Damien Batstone from AWMC at UQ, whose key research focuses on resource recovery using anaerobic digestion, drew attention to the age of many digesters at Australian utilities as a key factor in their poor performance and relatively low levels of biogas produced. The Conference keynote speaker, Dr sudhir Murthy, commented that in the US, particularly California, anaerobic digester gas production frequently exceeded plant needs and was fed into the electricity grid. Whether this would continue in the future in that state and others depended on its cost of production relative to other gas, including shale currently being available in US, as well as the fact that it is not an ideal substrate for producing electricity.
Day 2 On Day 2, NZ colleague Jacqui Horswell, whose contributions to the biosolids program regularly provide an insight into policies and concerns that are in focus for friends across the Tasman, delivered a paper titled Up the Pipe Solutions – Can You Change What Goes Down Your Drain?. This work reported results from a community education program involving schoolchildren. Goals sought in this study were: I.
II.
Workshop: CapaCity BuilDing in sourCE managEmEnt This workshop ran over two sessions and was chaired by Ray Borg, Co-Chair of the Specialist Network. In the first session, adam Cunningham, David greaves and Darshit Dalal from Barwon Water shared their experiences in developing the $94 million Northern Water Plant (NWP), a 7.5 ML/d reclamation plant,
to reduce the level of contaminants present in the municipal wastewater system ultimately ending in biosolids and where they came from
coupled with a 5 ML/d Class A advanced recycled water plant to
to improve students’ interest in science and initiate change in their behaviour when handling wastes.
served as a case study for subsequent discussion.
A comprehensive survey was designed with the help of a teacher. The students were required to take the survey home to identify products in their laundry, kitchen or bathroom that had ingredients they did not recognise or were concerned about, and to interview a parent or caregiver who was the primary household shopper about their motivations for purchasing household cleaning or personal care products. This tool was intended to stimulate students’ awareness of household products and their contents.
supply the Shell Geelong Refinery. This potable substitution frees up approximately six per cent of Geelong’s water demand and
The second session provided an opportunity for delegates to explore the recent history of source and trade waste management, best practice current examples and current challenges. A video was developed to give grounding to the student survey. The film provides a humorous but informative look at what goes down a household drain, what happens in an urban wastewater
some of the attendees at the source Management session.
august 2014 water
40
Conference report treatment system, and how this can impact on recreational and drinking water quality.
sourCE managEmEnt Workshop: traDE WastE poliCy anD stratEgy forum
Finally, a “hui” or community gathering, structured as a special workshop, was convened at the local meeting house. This brought together Year Nine students from the local high school, teachers, parents and members of the Kaikoura District Council, as well as prominent local community business owners actively involved in waste reduction – two elder women from the local runanga, and representatives from Enviroschools and the NZ Council for Educational Research.
This workshop addressed a number of problems and issues that source managers are dealing with daily and on which delegates freely commented. Topics addressed included: • The strengths, weaknesses and applicability of state regulations, with inconsistencies highlighted; • Methods for setting acceptance limits with customers, including negotiating increased or reduced limits;
This exercise provided an excellent student and adult education campaign to achieve improved behaviour. Plans are being made to expand the topics and communities to experience a similar program. A follow-up evaluation of this pilot would certainly seal the verdict on its value. In the same session, RMIT’s Barry Meehan, who, with colleagues William Rajendram and aravind surapaneni, has developed and run a unique and practical introductory program to understanding and managing biosolids from source to end use application, presented their paper Enrichment of the Curriculum – Incorporation of Biosolids into Environmental Science Programs at RMIT University. The paper outlined the way in which final and honours year biosolids projects are central to a class program that includes basic knowledge of biosolids, management and sustainable land application in Victoria. Delegates to this conference overwhelmingly enjoyed themselves. Special thanks go to the Conference Platinum sponsors, Arkwood
• Challenges in dealing with small rural councils forced to engage in trade waste management planning as a result of Council amalgamations, for example, as in Queensland; • Practitioners found it difficult to account for the treatment technologies their trade waste would encounter; • Environmental, economic and political influences on what are considered acceptable limits into sewer. Organic Recycling and Gold Sponsors Loop Organics and Wastelink, for their support. The trade displays and exhibits were well patronised and seemed to have many meetings with individuals making specific enquiries. The drinks session, sponsored by Paul Darvodelsky’s PSD on the evening of Day 1, before the Conference Dinner, was appreciated. Transpacific sponsored the tour on Day 3 – a fine day all round!
DON’T MISS OUT! If you haven’t yet booked into the September issue of Water Journal, you’d better be quick, as bookings close AUGUST 22. The September issue will feature the following topics: • • • • • • •
Urban & Regional Water Planning Stormwater & Urban Stream Health Membranes & Desalination Water Recycling & Fit-For-Use Treatment Industrial Water Treatment & Management Risk Management Health & Safety
This is the perfect environment to promote your brand, product or service to over 5,500 members and subscribers.
To book your advertisement, please contact Kirsty Muir, email: kmuir@awa.asn.au or tel: 02 9467 8408. water august 2014
JOUrna Journal of the australian Water association
POST APPRO
VED PP
PRINT POST APPROVED PP 100003880
100003880
Volume 41 no 5 AUGUST 2014
L Of the
aUS rrP $18.95 traLian
Water
aSSOci
atiOn
Volume 41 No 4 JUNE 2014 RRP $18.9
5
OZWATER
> Best Pape ’14 HIG > Confere r & Runner-Up HLIGHTS > Water nce & Wor kshop Reports > Water Leaders Foru m Innovatio > National n Water Forum Showca Awards se 2014 PLUS • Water Qual • Water Policy • ity • Odour Man Water Syste agement ms Ope rations
PUSHING WATER UPHILL...
could this simple solution be an answer to our renewable energy issues? see page 30. Plus > Biosolids & source Management > Managed aquifer recharge > Wastewater treatment > smart systems
For your convenience, the 2014 Australian Water Directory is now available online...
To view the digital version now visit www.awa.asn.au/WaterDirectory
technical papers
Application Of Sonar Technology For The Profiling Of Sludge In Wastewater Pond Systems
Biosolids & Source Management Influence Of Biosolids On Attaining Energy Neutrality At A WTP
An exploration of whether energy neutrality is achievable using anaerobic digestion and enhanced primary treatmentWPF Barber
Codigestion With Glycerol For Improved Biogas Production
Outcomes from two pilot-scale trials to quantify the benefits of codigestion for Sydney Water
M Dawson & S Fitzgerald
43 49
Stormwater Treatment Compatibility Of Stormwater Treatment Performance Data Between Different Geographical Areas
P Egodawatta et al.
53
A Moyse & R Martin
58
P Dillon et al.
62
Y Poussade et al.
68
J Sorbello & R Marck
75
A case study to assess the compatibility of stormwater treatment performance data
Managed Aquifer Recharge Can You Afford Managed Aquifer Recharge? Application of a decision support system for the staged implementation of ASR schemes in Adelaide
Using Urban Stormwater And Aquifers Or Reservoirs For Non-Potable And Potable Supplies
Key outcomes from the MARSUO research project
Wastewater Treatment This icon means the paper has been refereed
From Wastewater To Resource: A Technological Roadmap
An overview of a strategic research collaboration between Veolia Water and Sydney Water
Smart Systems Applications For Intelligent Water Network Systems
Case studies to demonstrate how water utilities can use smart systems to tackle a range of water issues
Smart Metering Enables Effective Demand Management Design
Why an early mixed-method baseline analysis is essential to design robust programs in remote communities
81 Aerial view of Gunbalanya, with the Arnhem Land escarpment beyond.
K Ross et al.
81
NEXT ISSUE
SEPTEMBER 2014 • URBAN & REGIONAL WATER PLANNING • MEMBRANES & DESALINATION • WATER RECYCLING & FIT-FOR-USE TREATMENT • INDUSTRIAL WATER TREATMENT • RISK MANAGEMENT • HEALTH & SAFETY
THE INFLUENCE OF BIOSOLIDS ON ATTAINING ENERGY NEUTRALITY AT A WASTEWATER TREATMENT PLANT An exploration of whether energy neutrality is achievable using a combination of anaerobic digestion and enhanced primary treatment WPF Barber
ABSTRACT Wastewater, sludge and subsequent biosolids are large inherent energy sinks and, in most cases, contain more energy than required to operate a treatment plant. This paper explores how the energy can be exploited to minimise plant demands. This study found that no single measure can help achieve energy neutrality; rather, a combination of processes. The use of anaerobic digestion was found to reduce energy demands by over a third, and by 60% when combined with enhanced primary treatment. Energy neutrality was potentially achievable by combining these processes with further energy recovery downstream via burning as a cake. However, this study highlighted the poor energy extraction capability of anaerobic digestion when considered in a plant-wide envelope.
INTRODUCTION When considering the quantity of inherent energy contained within wastewater flows entering a treatment plant, it is surprising how little of this energy is actually captured. Although aeration during biological treatment of wastewater is famously energy intensive, this demand is actually significantly lower than the amount of energy in the wastewater stream it is processing. In theory, under certain circumstances and configurations, it is possible to become energy-neutral or even export surplus energy. However, the way the sludge produced is processed is fundamental in overall energy recovery. ENERGY IN WASTEWATER
Various attempts have been made to conduct an energy balance over a wastewater treatment plant (Lobato et al., 2012). These attempts have gathered pace in recent years, with a growing
appreciation of the potential value in the various steams that flow through wastewater treatment. Many studies involve converting the carbon in wastewater into an energy stream. A recent study showed carbon balances for a couple of different wastewater stream configurations (Bernard et al., 2012). This study suggests that, for a standard configuration of primary and secondary treatment, 60% of the carbon entering the works will end up in anaerobic digestion, which will recover 24% of the (influent) carbon as biogas. In this instance the plant is expected to be 65–70% energy sufficient. However, the work did not state what level of nutrient removal was assumed for the study. A separate piece of work (Barber, 2013) shows the influence of wastewater treatment on energy balance between anaerobic digestion and aeration. Only two of the options modelled showed energy self-sufficiency, these being 1) when only carbon removal was required (i.e. no strict nitrogen consent); and 2) when enhanced primary treatment was installed. The latter configuration was also studied by Bernard and co-workers (2012), who showed similar energy sufficiency. However, studies based on carbon flows – in turn based on COD data – are potentially misrepresenting the energy value of the waste streams. When looking at the elemental composition of sludges they contain other material, such as hydrogen, which contribute to calorific value but are not picked up in a COD test (Barber, 2013). For example, use of the Dulong equation to determine the calorific value of primary sludge suggests a figure of 25,700 MJ/kg volatile substance. However, closer observation of the data reveals that the carbon content only contributes approximately 60% of the energy within the sludge. This suggests
that formal energy measurements using techniques such as bomb calorimetry would provide more accurate data than those based on COD alone. One study that followed this approach was conducted by Shizas and Bagley (2004), who measured calorific values of several wastewater streams inclusive of raw municipal wastewater. They measured figures of 3.2, 15.9, 12.4 and 12.7 MJ/kg dry substance for raw wastewater, primary sludge, secondary sludge and anaerobically digested mixed sludge respectively. The results for the sludges were consistent with previous (Zanoni and Mueller, 1982) and subsequent (Barber, 2007) measurements. From raw data provided by Shizas and Bagley it is possible to determine a theoretical figure from the Dulong equation assuming similar composition to sludge solids. Performing this calculation gives a figure of 2.8 MJ/kg dry material (compared with the measured 3.2 MJ/kg). Also, analysis of the data presented by Shizas and Bagley (2004) reveals no correlation between COD and calorific value. ENERGY DEMAND FOR AERATION
The energy demands for aeration depend on the level of treatment required (which defines the oxygen requirement), the process configuration and the efficiency of the device providing the oxygen. More recently, interest has been shown in manipulating the biological pathways to favour those that require less oxygen, and hence less energy. Table 1 summarises the oxygen demands for different processes. These oxygen requirements are converted to energy demands from knowledge of the efficiency of the devices used to blow the air/oxygen into solution. Efficiencies range from 0.7–2.0 (coarse bubble surface aeration)
AUGUST 2014 WATER
BIOSOLIDS & SOURCE MANAGEMENT
43
Technical Papers
BIOSOLIDS & SOURCE MANAGEMENT
44
Technical Papers up to and higher than 3.5 kg O2/kWh. The energy demands of providing air for wastewater treatment are significant, and typically account for between 50–70% of site power demand (WEF, 2009). Although energy demand for aeration systems is considered high, it is only a fraction of the energy entering a
wastewater treatment plant. A recent energy study conducted for Sydney Water (2013) shows that, for standard primary and secondary treatment, aeration energy consumes only a fraction of the energy entering the plant. This is shown in the energy (Sankey) diagram in Figure 1.
Table 1. Typical oxygen demands of wastewater treatment. Typical Oxygen Demand [kg O2/kg load removed]
Process Carbon removal only
0.9 – 1.2
Ammonia removal through nitrification on Activated Sludge Plant1
4.6
Total nitrogen removal through nitrite-shunt process2
3.4
Total nitrogen removal through Deammonification process
3
2.0
1. Here ammonia is oxidised to nitrate via nitrate. Used when there is no total nitrogen requirement 2. Similar to process 1 except processed at higher temperatures to influence kinetics to prevent additional oxidation of nitrate to nitrate, therefore decreasing oxygen requirements. For total nitrogen removal requires carbon addition. 3. Uses specialised chemolithotrophic organisms to use ammonia as electron donor with nitrite as electron acceptor in order to degrade ammonia all the way to nitrogen gas without the requirement of carbon.
ENERGY FROM SLUDGE
Energy can be recovered from sludge in numerous ways. The most common involves the production of methane-enriched biogas from anaerobic digestion. This biogas can then be used directly in a boiler, or to generate electricity and heat using a co-generation plant, or processed further to produce biomethane. Figure 2 shows a typical energy (Sankey) diagram for the production of energy from biogas from the digestion of 1 tonne dry sludge solids. Figure 2 shows that only approximately 10% of the sludge energy is captured during electricity production using cogeneration and that nearly 40% of the energy exits the digestion plant. Even if pre-treatment is applied to enhance anaerobic digestion, the figures change to approximately 15% electricity production and >30% in the digested biosolids. The study commissioned by Sydney Water (Sydney Water, 2013) showed that energy consumption of pre-treatment processing can be significant and ranges from 0.01 to as high as 0.085 kW/tonne dry sludge processed. To put this into perspective, the energy generation shown in Figure 2 is equivalent to 0.085 kW. In order to extract the remaining energy from the biosolids, assuming no fundamental changes in anaerobic digestion design, it is necessary to thermally process the sludge to release its energy.
Figure 1. Energy flows through wastewater treatment works based on primary and secondary treatment with anaerobic digestion of sludge produced.
Figure 2. Energy flows from digestion of 1 tonne sludge dry solids.
WATER AUGUST 2014
From a previous study (Barber, 2013) the calorific values of different sludges were determined from a combination of elemental analysis and use of the Dulong equation. Figures of 25,700, 21,800 and 23,400 kJ/kg volatile substance were determined for primary, secondary and blended sludge respectively. These figures compare favourably with a number of materials such as: lignite (16,500 kJ/kg); domestic waste (<14,000 kJ/kg); or glycerine (19,000 kJ/kg). The higher fat content of raw primary sludge means that its calorific value is approximately a quarter higher than for an equivalent amount of secondary sludge. However, upstream anaerobic digestion increases the ash content of the subsequent dry solids and this results in a drop in calorific value on a dry basis. A previous study based on measurements of energy content within sludge showed a correlation between ash content and calorific value (Barber, 2007).
Aeration Energy
Transport 1%
DW Power
Power recovery Drying power Thermal 0% Other 31%
Drying power 0% DW Liquor Treatment 8% DW Power 2%
DW Liquor Treatment Drying Power Aeration Energy 58%
Drying Thermal Power Recovery Power Pretreat Power Other Transport
Figure 3. Breakdown of energy demand across wastewater treatment for base-line scenario Using that correlation, it is predicted that standard and advanced anaerobic digestion reduce calorific value of raw sludge by approximately 20% and 30% respectively on a dry basis. However, some or all of this calorific value can be recovered by improved dewatering, as will be discussed later. This paper explores how the combined energy from wastewater sludge, whether from anaerobic digestion or thermal processing, or both, can influence the total energy demands of wastewater treatment in order to provide insight into the potential achievement of energy neutrality.
MODEL In order to determine the energy flows through wastewater treatment and energy production from sludge, a number of models were set up. Initial data on sludge yield, oxygen requirements and ammonia release/consumption was determined using the methods described by McCarty (1966; 1971). The data was recalculated under different conditions and sludge ages. Energy required for the aeration process was determined by modelling various configurations of secondary treatment based on the activated sludge process using standard equations and methods and equipment suppliersâ&#x20AC;&#x2122; information. Phosphorus removal by natural wastage was calculated using the equation provided by Rittmann and McCarty (2001). If required, additional phosphorus was removed by adding quantities of metal salts based on typical chemical requirements, and sludge production determined from stoichiometric requirements. Calorific value data was determined using the Dulong Equation (Technical Report, CEN/ TR 13767, 2004) using data on chemical composition from the literature.
Performance of downstream digestion was calculated using a model that combines correlations obtained from full-scale plant data and kinetics. The model would predict performance based on: type of sludge; sludge age; digester operating temperature; digester retention time and quantity of dead space (as described previously, Barber, 2005). Performance of downstream dewatering was based on a mixture of operational data from numerous sludges and analysis of literature results. With respect to anaerobic digestion pre-treatment, energy demands were determined based on a combination of supplier data and thermodynamic calculations. Also, the energy demand of additional liquor treatment, for example an increase in ammonia due to improved digestion, was determined and included in the energy balance. A similar approach was undertaken to model the energy flows for downstream biosolids processing, inclusive of dewatering, additional liquor treatment, drying and energy recovery. The baseline conditions for the model are given in Table 2. The standard sludge-processing configuration is based on anaerobic digestion and dewatering, unless stated otherwise, with 160 km transport to end use.
RESULTS IMPACT OF ANAEROBIC DIGESTION
The breakdown of power demand for the baseline, i.e. standard nitrification (Process 2 in Table 1) followed by anaerobic digestion with dewatering and land application, is shown in Figure 3. In this instance, total energy demand is 0.87 MW, which is equivalent to 0.428 kWhr/m3 influent treated. When the
impacts of anaerobic digestion are also included, this figure falls by approximately a third to 0.286 kWhr/ m3. Potentially, the influence of anaerobic digestion can be greater still if pretreatment or co-digestion is employed. In the case of the former, assuming a pre-treatment demand of 0.02 kWhr/t dry sludge processed (Sydney Water, 2013) and a biogas increase of 20%, the overall energy balance actually worsens to 0.336 kWhr/m3. Although, the biogas increases the benefit by 0.06 MWe, the pretreatment plant increases demand by 0.10 MWe. It becomes clear that in terms of energy balance alone there is equilibrium between additional biogas energy generated and increased energy consumed by the pre-treatment plant. In this example, the energy demand of the pre-treatment plant will need to drop to 0.012 kWhr/tonne dry solids processed to break even with an increase in biogas of 20%. Alternatively, biogas production can be increased by the addition of other high-energy wastestreams during codigestion. Biogas production was changed in the model to determine how much increase is required to enable energy neutrality for the base case scenario and a little more than a three-fold increase in biogas production was required. IMPACT OF ALTERNATIVE AERATION BIOLOGY
As previously mentioned, there is growing uptake in alternative aeration techniques to reduce overall aeration requirement. When these processes were modelled, they showed a significant decrease in overall plant energy demand. Compared with the baseline figure of 0.286 kWhr/m3 influent processed, site energy demand falls to 0.216 and 0.122 kWhr/m3 with nitrite-shunt and deammonification processes respectively. However, in neither case, with the consent required in the example, is the plant energy neutral. For this to happen, it is necessary to also increase the predicted biogas production. In the case of deammonification, biogas production will have to increase over the norm by 200% and this increases further to 250% for nitrite-shunt. Clearly, pretreatment is not capable of increasing biogas by these levels; however, these increases in biogas could potentially be met by the addition of high-energy substrates such as glycerol.
AUGUST 2014 WATER
BIOSOLIDS & SOURCE MANAGEMENT
45
Technical Papers
BIOSOLIDS & SOURCE MANAGEMENT
46
Technical Papers IMPACT OF ENHANCING PRIMARY SETTLEMENT
Another way of reducing site demand is to enhance the performance of primary settlement. This has dual benefits. Firstly, additional primary sludge is produced over secondary sludge. As shown before, primary sludge has approximately a quarter more inherent energy than its secondary counterpart, but in addition, load is diverted away from secondary treatment towards anaerobic digestion. Previous work (Barber, 2013) has shown a reduction in aeration energy of over 20% compared with an increase in biogas production of nearly 30% when compared to a standard configuration of primary with secondary treatment. When considering the baseline scenario, site-wide power demand drops by a further 40% from 0.286 to 0.159 kWhr/m3 influent processed. The results for the alternative aeration configurations are 0.102 for nitrite-shunt (compared to 0.216 kWhr/m3 previously) and 0.027 kWhr/m3 (compared to 0.122 kWhr/m3 previously) for deammonification. The data imply that a combination of enhanced primary treatment with full-stream deammonification is now approaching energy neutrality depending on site-specific conditions. In this example, an increase in biogas production of 15% (by minor process adjustments) or 30% (to allow for pretreatment processing power demand) would be required. IMPACT OF DOWNSTREAM ENERGY RECOVERY FROM BIOSOLIDS BURNING
This scenario was modelled with and without drying of the biosolids and also with and without a pre-treatment process known as thermal hydrolysis. This process was chosen as it is known to fundamentally impact dewatering performance of biosolids by up to 10 percentage points (Evans, 2006). In combination with enhanced solids destruction, its employment has had a large impact on reducing downstream energy demands of thermal processes (Barber, 2010). When looking at only burning of dewatered cake, overall demand increases to 0.88 MWe (from 0.87) and benefits increase from 0.29 MWe (biogas only) to 0.36 MWe when including energy derived from burning. This leaves a sitewide energy demand of 0.256 kWhr/m3 influent (down from 0.286 earlier). Biogas
WATER AUGUST 2014
energy accounts for 85% of the total benefits in spite of more energy entering the thermal processing plant than recovered from the biogas. This is due to lower energy conversion efficiencies at the thermal processing plant. This suggests that future efforts to improve the relatively poor energy recovery currently experienced around anaerobic digestion would yield greater benefits than energy recovery downstream. If thermal hydrolysis is used to improve dewatering, the overall energy requirement drops further to 0.233 kWhr/ m3. Although the thermal hydrolysis plant consumes 0.048 MW it increases energy outputs at both the digestion plant (of 0.073 MW) and the thermal processing plant (of 0.020 MW). Energy output at the thermal processing plant increases slightly due to the greater impact of improved dewatering on calorific value of the biosolids than the reduction in calorific value caused by a loss of volatile content. Previous work showed that the drop in dry solids calorific value caused by volatile solids reduction as a result of improved digestion caused by thermal hydrolysis, could be offset by an improvement of two percentage points in dewatering (Barber, 2010). When drying is employed, the energy recovery at the thermal processor is greatly enhanced. However, this comes at the expense of additional power required for electrical components, such as drives and conveyors and, more importantly, thermal energy for water evaporation. Figure 4 shows the impact of drying energy demand on overall power need.
Power Recovery Power 1% Pretreat Power 0%
Drying Thermal 44%
As mentioned previously, thermal hydrolysis impacts downstream thermal processing due to improved dewatering and enhanced destruction of sludge during digestion. When compared with the previous example, overall energy demand drops significantly by nearly a quarter to 0.477 kWhr/m3 in spite of the additional energy demand of liquor treatment and thermal demand for the thermal hydrolysis plant itself. Figure 5 shows the breakdown of energy demands for drying and energy recovery with and without thermal hydrolysis being present. The overall energy consumption drops by approximately 15%, while energy generation overall increases by a quarter
Aeration Energy
Transport 0% Other 16%
The model shows an increase in power generation at the thermal processing plant of 0.2 MWe up to 0.207 MWe. The contribution of burning power generation to overall generation (inclusive of biogas energy) has now increased to 40% (from only 15% for cake burning). However, this increased energy output has come at the expense of 0.087 MW and 0.787 MW of electrical and thermal energy respectively. When the units are normalised, the overall power consumption is now 0.610 kWhr/ m3 influent. Figure 4 shows that, unlike most wastewater treatment configurations when aeration controls overall energy demand, it is now the demand of drying that has the greatest influence. When reviewed in the light of previous findings of this study, this result suggests that no plant employing drying will ever achieve energy neutrality even if preceded by enhanced primary treatment combined with deammonification.
DW Power DW Liquor Treatment Aeration Energy 29%
Drying Power Drying Thermal Power Recovery Power Pretreat Power Other Transport DW Power 1%
DW Liquor Drying power Treatment 5% 4% Figure 4. Breakdown of energy demand across wastewater treatment for scenario including thermal drying of biosolids.
Energy Demand [MW]
2 1.8
Transport
1.6
Other
1.4
Pretreat Power
1.2
Power Recovery Power
1
Drying Thermal
0.8
Drying Power
0.6
DW Liquor Treatment
0.4
DW Power
0.2
Aeration Energy
0
Without Thermal Hydrolysis
With Thermal Hydrolysis
Figure 5. Breakdown of energy demand across wastewater treatment for scenario including thermal drying of biosolids. in the presence of thermal hydrolysis. The main energy reduction is observed in the drying facility where energy demand is reduced by 40%. Other reductions in energy are seen during dewatering (fewer solids to dewater, although there is an increase in liquor treatment power), and transport to energy recovery centre (10% reduction due to fewer solids to transport). This compares to a transport energy reduction of nearly 50% for the options involving cake burning.
DISCUSSION This work highlights the fundamental impacts, both positive and negative, of biosolids processing on overall energy requirements of a wastewater treatment works. Compared to a base-line situation, anaerobic digestion was found to decrease energy demand by a third. However, installation of pre-treatment did not appear to have an impact as the energy gains achieved through biogas increases were annulled by energy demands of the pre-treatment process. This study found that on a normalised basis, a 10% increase in biogas (processed through cogeneration) was equivalent to 0.009 kW/t dry raw solids digested. In other words, for a positive impact on energy balance, a pre-treatment plant that increases biogas energy by 10% will have to have a power demand of below 0.009 kW/t dry solids it processes. Regarding thermal hydrolysis, in the absence of drying, the overall energy demand is dependent on the configuration of the co-generation engines. In the worst-case scenario, the energy demand of the hydrolysis plant effectively cancels out the energy benefit
of the improved digestion performance. However, with re-configured engines, the energy required by the system can be significantly reduced resulting in a net positive energy balance. This is the case at Davyhulme Wastewater Treatment Plant in Manchester in the UK (Belshaw et al., 2013), which generates 10 MW electricity and is a net energy exporter. Another configuration that was found to be highly dominant was enhancement of primary treatment. This reduced site energy demand by 60% compared with the baseline scenario, due to a combination of reduced load to the subsequent aeration plant and increased performance of the anaerobic digestion plant. Previously (Barber, 2013) it was noted that primary sludge not only digests far better than its secondary analogue, but contains a quarter more energy. This suggests that enhancing primary treatment is an important consideration when attempting to reduce site power demands. As highlighted in Figure 2, most energy in anaerobic digestion is not actually in the biogas, but in the biosolids leaving the plant. Potentially, this is a valuable energy sink. In this study, this was explored by evaluating the impact of further energy recovery via burning as a fuel in an appropriate facility. Burning cake did reduce overall energy demand by a further 10% compared to anaerobic digestion followed by a nonenergy recovery outlet. However, for dewatered cake the additional energy recovered only accounted for 15% of the combined energy benefit of digestion and burning. This is due to a reduced efficiency at the energy recovery facility compared
with cogeneration, and also the energy demands of the facility itself. This infers that effort should be applied to further enhance the current performance of anaerobic digestion so that as little energy as possible leaves the digester. In order to maximise the benefits of downstream energy recovery, drying to produce pellets was studied. While the energy output at the energy recovery plant was increased three-fold and now accounted for 40% of the total energy recovered (by digestion and burning), this came at a large expense of energy required for water evaporation, which completely expunged any downstream energy gains. Drying increased overall plant energy demand by over 200% and became more influential than aeration. Use of thermal hydrolysis was found to significantly improve energy balance in the presence of drying and downstream energy recovery. Here, energy requirements were reduced by nearly a third and this was due to a combination of improved digestion (i.e. less to dry) and improved dewatering (i.e. less water to evaporate). The results of this study highlight that achievement of energy neutrality is unlikely to be possible by any one technique, but will require a combination of processes. Even use of mainstream deammonification does not achieve energy neutrality based on a standard configuration of wastewater treatment, unless biogas production is increased by over 200%. Strass wastewater treatment in Austria achieves a low overall energy demand of 0.314 kWhr/m3, however this is accomplished by alternative biological treatment through deammonification and imports of other waste streams to increase biogas production (Wett et al., 2007). Figure 6 summarises the findings of this study and looks at the impacts of combining several process steps in the potential attainment of energy neutrality. The greatest energy recovery benefit was found by combining enhanced primary treatment with thermal hydrolysis followed by digestion (and dewatering) with cake burning. Addition of drying resulted in too high an energy demand to provide benefit, and energy neutrality through drying only appears possible by combining enhanced primary treatment with Annamox followed by thermal hydrolysis.
AUGUST 2014 WATER
BIOSOLIDS & SOURCE MANAGEMENT
47
Technical Papers
BIOSOLIDS & SOURCE MANAGEMENT
48
Technical Papers Barber WPF (2007): Observing the Effects of Digestion and Chemical Dosing on the Calorific Value of Sewage Sludge, Paper IWA Specialist Conference: Moving forward Wastewater Biosolids Sustainability: Technical, Managerial, and Public Synergy, June 24-27, 2007, Moncton, New Brunswick, Canada, pp 351–358. Barber WP (2005): The Effects of Improving Sewage Sludge Digestion, Journal of the Chartered Institution of Water and Environmental Management, 19, 3, pp 214–224. Belshaw D, Edgington RM & Jolly M (2013): Commissioning of United Utilities Thermal Hydrolysis Digestion Plant at Davyhulme Waste Water Treatment Works, Proceedings of the 18th European Biosolids and Organic Resources Conference, November, Manchester. Bernard JF, Gurieff N, Chauzy J, Amiel C, Schrötter, J-C & Vince F (2102): From Wastewater Treatment Plant to Bio-refinery. Advanced Resource Recovery Processes, Paper presented at AWA Biosolids V Conference, Gold Coast.
Figure 6. Impact of process configurations on potential for energy neutrality. Key: AD = Anaerobic Digestion; PrT = Anaerobic Digestion Pre-Treatment; TH = Thermal Hydrolysis; ERCake = Energy Recovery from Dewatered Cake; EnP = Enhanced Primary treatment; ERPellets = Energy Recovery from pellets dried at 92% dry solids. Blue bars = aeration based on standard FBDA activated sludge; Red bars = aeration based on nitrite-shunt; Olive-green bars = aeration based on full-stream deammonification.
CONCLUSIONS The production and type of sludge and subsequent biosolids generated at a wastewater treatment works is highly influential on the potential to achieve energy neutrality. While attainment of energy neutrality is site-specific, this study has highlighted ways to assist with attainment of this goal. Additionally, energy neutrality is highly influenced by licensed consent, with it being increasingly difficult to attain as consent tightens. Perhaps a better unit for comparision between plants would be kWhr/kg load removed rather than the kWhr/m3 currently employed. Investment in enhancing primary treatment to reduce load as much as feasibly possible appears fundamental in reducing site energy demands. The ultimate endpoint of this approach would be to anaerobically digest the entire influent with trace load exiting for further treatment. This is currently the case at Melbourne Water’s Western Treatment Plant, which is a lagoon-based system fronted by anaerobic treatment with energy recovery. In addition, particular attention should be paid to performance of anerobic digestion, which even with pre-treatment allows most of the energy entering it to escape in the effluent. Capturing the energy around the digestion plant appears far more energy efficient than capturing it downstream.
WATER AUGUST 2014
When considering thermal processing and energy recovery, dewaterability of the biosolids is fundamental as this has a significant impact on the thermal energy required to process the biosolids. In this regard, use of thermal hydrolysis was found to be useful due to destruction of more biosolids upstream and reducing water evaporation requirements downstream.
THE AUTHOR Dr William (Bill) Barber (email Bill.Barber@aecom. com) works on global biosolids projects within AECOM’s Technical Practice Network, and is currently based in Maryland, US. Bill has worked in research and development, technology supply, engineering consultancy and for a water utility. In these roles, he has developed biosolids strategies and worked on a number of biosolids technologies in Europe, Australasia, Asia and the US.
REFERENCES Barber WPF (2014): Influence of Wastewater Treatment on Sludge Production and Processing, Water and Environment Journal, 28, 1, pp 1–10. Wiley Publishing. Online. Barber WPF (2010): The Influence on Digestion and Advanced Digestion on the Environmental Impacts of Incinerating Sewage Sludge – A Case Study from the UK; Residuals and Biosolids 2010, Water and Environment Federation; Savannah, Georgia. May 23– 26.
Evans T (2006): Sludge Dewatering Performance – A Survey Of Real Operational Performance, Proceedings of the 11th Aquaenviro Biosolids and Biowastes Conference, 13–15 November, 2006. Lobato LCS, Chernicharo CAL & Souza CL (2012): Estimates of Methane Loss and Energy Recovery Potential in Anaerobic Reactors Treating Domestic Wastewater, Water Science & Technology, 66, 12, pp 2745–2753. McCarty PL (1966): Kinetics of Waste Assimilation in Anaerobic Treatment, Developments in Industrial Microbial Sciences, 7, American Institute of Biological Sciences, Washington DC. McCarty PL (1971): Energetics and Kinetics of Anaerobic Treatment – Chapter 6, In: RF Gould (ed): Anaerobic Biological Treatment Processes, 159th Meeting of the American Chemical Society, Houston, Tex., Advances in Chemistry Series No 105, Washington DC. Painter HA (1986): Nitrification in the Treatment of Sewage and Waste-Waters – Chapter 10. In: JI Prosser (ed). Nitrification. Special Publications of the Society for General Microbiology, 20, pp 185– 211, IRL Press, Oxford, UK. Rittmann BE & McCarty P.L (2001): Environmental Biotechnology: Principles and Applications, McGraw-Hill Publishers, NY, 2001. Shizas I & DM Bagley (2004): Experimental Determination of Energy Content of Unknown Organics in Municipal Wastewater Streams, Journal of Energy Engineering, 130, 2, pp 45–53. Sydney Water (2013): Anaerobic Digestion Literature Review, Current and Future Trends, Report No 60297785, AECOM, July. WEF (2009): Water Environment Federation Manual of Practice No. 32, Energy Conservation in Water and Wastewater Facilities, ISBN-13: 978-0071667944, Alexandria, VA. Wett B, Buchauer K & Fimml C (2007): Proc. IWA Leading Edge Technology Conference, Singapore, Asian Water, 21-24 September 2007. Zanoni AE & Mueller DL (1982): Calorific Value of Wastewater Plant Sludges. Journal of Environmental Engineering Division (American Society of Civil Engineering, 108, pp 187–195.
CODIGESTION WITH GLYCEROL FOR IMPROVED BIOGAS PRODUCTION Outcomes from two pilot-scale trials to quantify the benefits of codigestion for Sydney Water M Dawson, S Fitzgerald
ABSTRACT Codigestion of organic wastes during anaerobic treatment of municipal wastewater was identified, as part of Sydney Water’s Energy R&D Program, as one way in which Sydney Water can optimise solids processing and biogas production. Sydney Water aims to harness the natural anaerobic digestion process to maximise its renewable energy generation and possibly expand its services to customers beyond traditional water industry services. To quantify the potential benefits of codigestion for Sydney Water, two pilotscale glycerol codigestion experiments, with continuous and intermittent dosing, were completed. The outcomes from these trials informed the implementation of a full-scale, 12-month glycerol codigestion trial at a wastewater treatment plant.
INTRODUCTION Since 2011, Sydney Water’s Energy R&D Program has identified costeffective opportunities and approaches to improve energy efficiency and energy recovery from wastewater. The research results from the program have been incorporated into day-to-day operations both to optimise existing wastewater treatment practices and to develop new approaches for energy and other resource recovery. A key component of the Energy R&D Program has been the Digester Research Program, aimed at investigating the potential for, and possible benefits of, codigestion and other technologies to increase biogas production from our existing facilities. Codigestion of organic wastes with municipal wastewater to increase biogas production, and as a sustainable means of waste disposal, has been successfully implemented by many wastewater utilities worldwide, such
as East Bay Municipal Utility District (EBMUD) in California and Christchurch City Council. Within Australia, there is increasing interest in codigestion, with many water utilities, such as Yarra Valley Water, Western Water and SA Water, undertaking various codigestion studies and trials. The main drivers for Sydney Water are to improve the cost-effectiveness of wastewater treatment operations, maximise renewable energy generation and potentially expand services to customers in the future. Sydney Water has 14 wastewater treatment plants with anaerobic digestion facilities. Eight of these plants have cogeneration units, producing over 53,000 MWh of electricity per year. Overall, Sydney Water generates up to 20% of electricity needs. However, some plants are more energy self-sufficient than others. For example, Bondi Wastewater Treatment Plant is largely self-sufficient, generating over 90% of its energy needs. Codigestion to maximise renewable energy production can be approached in two ways. Firstly, it can be used to increase overall baseline energy production through continuous dosing of a co-substrate. This is useful at plants where a consistent increase in energy generation is required. Secondly, codigestion can increase energy production at times when energy demand outstrips internal supply through intermittent dosing of a co-substrate. Figure 1 illustrates the typical energy deficit, energy consumption minus energy generation, at the Bondi Wastewater Treatment Plant over a 24-hour period. Although biogas is captured and used in cogeneration engines, peak energy demands cannot be met due to the limited biogas storage facilities available.
Figure 1. Energy deficit over a 24-hour period at a wastewater treatment plant with cogeneration facilities. This is not an uncommon situation for wastewater treatment plants with cogeneration facilities. A pre-feasibility study of codigestion for Sydney Water was completed in 2011. The study showed that codigestion can be used to increase biogas production to improve energy generation, but the main restriction to implementation is the limited anaerobic digester capacity available. However, the study found organic wastes with high biomethane potential, such as glycerol, could be economically viable at some of Sydney Water’s existing wastewater treatment plants. Glycerol is a by-product generated during the production of biodiesel from renewable feedstocks, such as vegetable oil, waste cooking oils and animal fats. The pre-feasibility study suggested that it could have synergistic benefit when added to the digestion process and could produce a significant amount of biogas with limited residue. The economic analysis noted that the electricity produced from adding 1% (volume substrate/volume raw sludge) glycerol to a digester could be worth three times the gylercol cost through electricity and renewable energy credits. In order to quantify the costs and benefits of codigestion, two 50-litre pilot anaerobic digesters, complete with a Supervisory Control and Data Acquisition unit (SCADA) were constructed (Figure 2).
AUGUST 2014 WATER
BIOSOLIDS & SOURCE MANAGEMENT
49
Technical Papers
BIOSOLIDS & SOURCE MANAGEMENT
50
Technical Papers • Intermittent dosing could enable codigestion to increase biogas production periodically to match the energy requirements of the plant.
Figure 2. Two 50-litre pilot anaerobic digesters. These pilot digesters have been used to determine the expected increase in biogas production from glycerol codigestion and to inform the development of a codigestion implementation plan across Sydney Water’s operations, including a full-scale 12-month trial of codigestion with glycerol. The key research questions to be answered by the pilot digester codigestion experiments were: • Quantify change in production and composition of methane in biogas;
Laboratory analysis of raw and digested sludge was conducted to monitor the performance of the pilot digester and the impact of glycerol addition on digester performance. Testing included alkalinity, chemical oxygen demand (COD), total organic acid (TOA), total solids (TS), volatile solids (VS) and pH for digested sludge, and TS, VS and COD of raw sludge. Biogas composition testing for CH4, CO2 and H2S, was conducted onsite.
All three experiments described below used the same glycerol sample: 1.
Continuous 1% (v/v) glycerol addition. This trial ran for 40 days from 17 October 2012 until 25 November 2012.
2.
Continuous 2% (v/v) glycerol addition. This trial ran for 21 days from 28 November 2012 until 18 December 2012.
3.
Continuous 3% (v/v) glycerol addition. This trial ran for 21 days from 18 December 2012 until the 7 January 2013.
• Characterise glycerol and identify potential contaminants.
INTERMITTENT DOSING EXPERIMENTS
METHODOLOGY
These two experiments were repeated for three different sources of glycerol: one pure and two crude glycerols:
Two 50-litre pilot anaerobic digesters (a control and a test rig) were inoculated with digested municipal wastewater sludge and fed with raw sludge at a rate of 2.5 litres per day. The pilot digester was continuously stirred and sludge was recirculated via a peristaltic pump. It had a solids retention time of 20 days. A SCADA system maintained the digesters at 35.0–35.2°C and 12–13kPa. The gas pressure, liquid pressure and gas flow were all monitored and recorded by instrumentation. Prior to adding glycerol, the pilot digesters were operated until biogas production stabilised to determine the ‘baseline’ biogas production. Two different glycerol dosing methods were trialled to test whether: • Continuous dosing would result in a constant increase in biogas production over time, without affecting digester performance;
WATER AUGUST 2014
Figure 3. Total biogas produced during continuous 1% (v/v) glycerol dosing.
CONTINUOUS DOSING EXPERIMENTS
• Compare the results of biogas production from different glycerol sources; • Determine the time lag between glycerol injection and increased biogas production;
continuous dosing, this concentration of glycerol ultimately had a limiting effect and prevented further production of biogas (Figure 5).
1.
0.63% (v/v) dosed six times at hourly intervals.
2.
3.0% (v/v) dosed six times at hourly intervals.
RESULTS QUANTIFY THE INCREASE IN BIOGAS PRODUCTION FROM GLYCEROL CODIGESTION
Laboratory and on-site testing showed that glycerol dosing for all experiments significantly increased biogas production without causing any detrimental effect on digester operation. The continuous dosing results, as illustrated in Figures 3 and 4, showed that total biogas production increased by approximately 50% with 1% (v/v) glycerol dosing and 90% with 2% (v/v) glycerol dosing. While there was an initial increase in biogas production for the 3% (v/v)
Figure 4. Total biogas produced during continuous 2% (v/v) glycerol dosing.
Figure 5. Total biogas produced with 3% (v/v) glycerol dosing. Intermittent dosing results also indicate a 50% increase in biogas production above baseline levels over the six-hour dosing period at the 0.63% (v/v) dosing rate. A 3% (v/v) dosing rate produced an 80% increase over the six-hour dosing period. COMPARE THE BIOGAS COMPOSITION FROM CODIGESTION WITH DIFFERENT GLYCEROL SOURCES
Limited data points from the biogas composition analysis during the continuous dosing experiment showed that the amount of CH4 and H2S in the biogas varied at different times during the experiment (Table 1). This may indicate that a change in biogas composition could be expected over time. More regular analysis needs to be
Table 1. Composition of biogas produced during the 1% (v/v) continuous dosing trial. Biogas composition CH4 (%)
Sample Date
Control
24 Oct 30 Oct
CO2 (%) Test
Control
58.8
58
58.8
57.9
30 Oct
58.9
30 Oct 21 Nov
GLYCEROL CHARACTERISATION
H2S (ppm) Test
Control
Test
40.2
41
562
396
40.2
41.1
571
396
58.1
40.3
41.1
547
243
58.7
57.9
40.2
40.9
550
233
58.7
57.9
40.8
41.9
594
326
Table 2. Composition of biogas produced during the intermittent dosing trial for different glycerol sources and dosing rates. Dosage
Glycerol
Composition
0.63% (v/v)
3.0% (v/v)
Crude 1
Crude 2
Pure
Replicate
1
2
1
2
1
2
CH4 (%)
54.1
58.1
59.8
59.7
54.6
55.5
CO2 (%)
29.6
37.1
40.1
40.1
38.6
39.6
O2 (%)
0.80
0.10
0.00
0.00
0.2
0.00
Other (%)
15.9
4.9
0.2
0.2
6.1
5.2
H2S (ppm)
375
537.5
657.9
680.8
424.4
439
Replicate
1
2
1
2*
1
2
CH4 (%)
59.4
59.7
55.5
41.9
55.4
55.4
CO2 (%)
39.2
39.9
38.3
28.8
39.7
40.8
O2 (%)
0.00
0.01
0.02
0.02
0.00
0.00
Other (%)
1.3
0.4
6.2
29.9
4.9
3.7
H2S (ppm)
993.8
621.7
420.3
178.9
386.9
3 .2
*invalid results due to gas leak in system Table 3. Physico-chemical properties of crude and pure glycerols. Characteristic
Glycerol source Crude 1
Crude 2
Pure
Appearance
Pale brown
Amber
Clear
Odour
Mild odour
Grain-like odour
Odourless
8-9
4
6.7
Boiling point (ºC)
>130
>130
290
Solubility in water
Highly soluble
Highly soluble
Highly soluble
Na content (mg/L)
16,939
40
0
pH
K content (mg/L)
454
119
0
Specific gravity (@ 25 ºC)
1.25
1.22-1.24
1.26
Glycerol content (%)
~50
~75-85
≥ 99
1,140
1,030
1,048
COD (g/L)
conducted to quantify any long-term change to CH4 and H2S compositions. The biogas composition from the intermittent dosing trials (Table 2) was relatively consistent, with all glycerol sources and dosing rates producing biogas with a CH4 content of between 54% and 60%. This is a similar level to that expected from anaerobic digestion without glycerol addition.
in biogas production occurred four to five hours after the initial dose for both 0.63% and 3% dosing rates.
IDENTIFY THE TIME LAG BETWEEN GLYCEROL INJECTION AND BIOGAS PRODUCTION
The results for the crude glycerol sources trialled during the intermittent dosing experiments are illustrated in Figures 6 and 7. The results show an increase in biogas production almost immediately following dosing. The maximum increase
The results from the characterisation of the one pure and two crude glycerols used in the Intermittent trials is shown in Table 3. The COD content of all three glycerols was not significantly different, with Crude Glycerol 1 having the highest COD concentration of 1,140 g/L. The most significant difference between the sources of glycerol is the sodium and potassium concentration. Sodium concentrations in the digester of greater than 3g/L are toxic to methanogenic bacteria, which are essential for the final stage of the anaerobic digestion process. This may be of concern if Crude Glycerol 1 was dosed at a sufficiently high concentrations.
DISCUSSION Results show that both intermittent and continuous dosing of glycerol into an anaerobic digester can increase biogas production. Both methods may be options for increasing energy production according to the requirements of the plant, without any detrimental effect on digester operation and digested sludge quality. The site-specific experimental results for Bondi WWTP give guidance on the dose and timing of dosing for the implementation of a full-scale trial. Higher doses of glycerol produced greater volumes of biogas for all experiments. However, it was seen that intermittent dosing with 0.63% (v/v) glycerol produced more biogas per unit of glycerol added than 3% (v/v) dosing. This shows that the most economic dose may not be that which yields the largest absolute volume of biogas. The most appropriate dosing regime will depend on sludge characteristics of the plant, COD content of the glycerol and energy generation required. The results also showed that there is almost no timelag between dosing glycerol and seeing an increase in biogas production. This result will inform the dosing regime such that the biogas generation and energy production can fill the energy deficits in a 24-hour cycle.
CONCLUSION The results indicate that both continuous and intermittent dosing methods can be used to successfully increase biogas production from anaerobic digestion.
AUGUST 2014 WATER
BIOSOLIDS & SOURCE MANAGEMENT
51
Technical Papers
BIOSOLIDS & SOURCE MANAGEMENT
52
Technical Papers Choosing the most appropriate method for implementation at a WWTP will depend on many factors, including: • The daily energy deficit profile at the plant; • The available spare capacity of existing cogeneration engines or the cost-effectiveness of purchasing additional capacity; • The price returned for supplying electricity back to the grid; • The available storage facilities for cosubstrates on site; • The outcomes of discussions between licencing regulators and the water utilitiy to allow glycerol to be brought onto the WWTP site.
Figure 6. Biogas production over time from a 0.63% vol/vol crude glycerol addition.
Intermittent dosing of glycerol directly into the primary anaerobic digester will be implemented at full scale at Bondi Wastewater Treatment Plant in July 2014. This trial will further quantify the benefits and help inform future feasibility assessments for codigestion at Sydney Water wastewater treatment plants.
ACKNOWLEDGEMENTS Thanks to the many internal and external stakeholders who contributed to Sydney Water’s Digester Research Program, which helped shape Sydney Water’s vision for codigestion. In particular, we acknowledge Long Nghiem and Patrick Manassa from the University of Wollongong and Babu Gomes, Derek Van Rys, Glenn Austin, Tung Nguyen, Tony Williamson, Bondi WWTP production officers, Wayne Jackson, Phil Woods, Brendan Galway, Sarah Vierboom and Nicola Nelson from Sydney Water.
Figure 7. Biogas production over time from a 3.0% vol/vol crude glycerol addition.
THE AUTHORS
Shona Fitzgerald
Marcia Dawson (email: marcia.dawson@sydneywater. com.au) is a Strategic Analyst at Sydney Water. She has 10 years’ experience in water covering best practice planning, demand forecasting, codigestion research and analytics.
(email: shona.fitzgerald@ sydneywater.com.au) is a Scientist at Sydney Water with a particular interest in treatment processes and resource recovery and a member of the AWA NSW Branch Committee.
There are surprising opportunities when you work in water
Managed by
Search no longer! Searching for the beSt S St WATER AUGUST 2014 candidateS for your company?
Searching for the lateSt late job opportunitieS in the water Sector? opportunitie
Visit www.h2oz.org.au
53
Technical Papers
A case study to assess the compatibility of stormwater treatment performance data between two geographical regions P Egodawatta, J McGree, B Wijesiri, A Goonetilleke
ABSTRACT Using a case study approach, this paper presents a robust methodology for assessing the compatibility of stormwater treatment performance data between two geographical regions in relation to a treatment system. The desktop analysis compared data derived from a field study undertaken in Florida, USA, with South-East Queensland (SEQ) rainfall and pollutant characteristics. The analysis was based on the hypothesis that, when transposing treatment performance information from one geographical region to another, detailed assessment of specific rainfall and stormwater quality parameters is required. Accordingly, characteristics of measured rainfall events and stormwater quality in the Florida study were compared with typical characteristics for SEQ. Rainfall events monitored in the Florida study were found to be similar to events that occur in SEQ in terms of their primary characteristics of depth, duration and intensity. Similarities in total suspended solids (TSS) and total nitrogen (TN) concentration ranges for Florida and SEQ suggest that TSS and TN removal performances would not be very different if the treatment system is installed in SEQ. However, further investigations are needed to evaluate the treatment performance of total phosphorus (TP). The methodology presented also allows comparison of other water quality parameters. Keywords: Stormwater quality; stormwater treatment.
INTRODUCTION Stormwater runoff transports a range of pollutants of both natural and anthropogenic origin and is a significant non-point source of urban water pollution (Al Bakri et al., 2008). For effective
removal of stormwater pollutants, it is important to employ treatment technologies that are appropriate to site and rainfall characteristics. A range of engineered stormwater treatment systems are marketed by various commercial vendors. In this context, it is important to ascertain the treatment performance of these systems under rainfall characteristics specific to a region. This requires stringent monitoring of the treatment system for a specified suite of rainfall events. Performance evaluation of this nature is highly resource-intensive and time consuming. As rainfall characteristics often vary between different geographical regions, there is concern regarding the performance of an engineered stormwater treatment system in a geographical region that is different to the region where it was originally evaluated. There is limited guidance provided in published literature regarding possible methodologies that can be used for assessing the compatibility of treatment performance data between different geographical regions. Using a case study approach based on comparing data from a study undertaken in Florida, USA, with SouthEast Queensland (SEQ) rainfall and pollutant characteristics, this paper presents a robust methodology that could be used for assessing the transference of treatment performance data between two geographical regions. The approach includes comparison of key rainfall and pollutant characteristics that are most influential in defining the performance of a stormwater treatment system. The methodology also allows comparison of a range of water quality parameters.
METHODOLOGY FLORIDA STUDY
The performance data was obtained from the field testing of a membrane filtration stormwater treatment device. The field study was conducted by the University of Florida in accordance with the Technology Acceptance Reciprocity Partnership (TARP) and Virginia Technology Assessment Protocol (VTAP) field test protocols. Further details of this study are provided in UoF (2011). During the field testing, samples were taken pre- and post-treatment for each monitored storm event to assess the pollutant removal performance. The collected samples were analysed for a range of parameters, including total suspended solids (TSS), total nitrogen (TN) and total phosphorus (TP). Removal performances of 89% for TSS, 51% for TN and 59% for TP have been reported (UoF, 2011). The transference of these removal efficiencies under SEQ conditions of rainfall and water quality characteristics is the focus of this paper. APPROACH ADOPTED FOR COMPARISON OF TREATMENT PERFORMANCE
Performance of a stormwater treatment system is typically influenced by stormwater inflow characteristics and inflow pollutant characteristics (Clark and Pitt, 2012). Therefore, when transposing treatment performance information from one geographical region to another, detailed assessment of runoff and stormwater quality data is required. Initially, the rainfall characteristics were assessed on the basis of their direct effect on runoff characteristics and, in turn, pollutant wash-off (Egodawatta et al., 2007). In this
AUGUST 2014 WATER
STORMWATER TREATMENT
COMPATIBILITY OF STORMWATER TREATMENT PERFORMANCE DATA BETWEEN DIFFERENT GEOGRAPHICAL AREAS
54
Technical Papers
2500
Total Annual Rainfall 10 year average rainfall Trend Line
2000
STORMWATER TREATMENT
1500 1000 500 0 1950
1960
1970
1980
1990
2000
2010
160 Number of wet days per year
140
10 year average of number of wet days
120 100 80 60 40
1950
1960
1970
1980
1990
2000
2010
Figure 1. Analysis for selecting representative rainfall years using Brisbane Airport weather station data. assessment, characteristics of monitored Florida rainfall events (provided in UoF, 2011) were compared with typical rainfall characteristics for SEQ. Rainfall records obtained from the Bureau of Meteorology weather station at Brisbane Airport were used for this analysis. Long-term rainfall trends were investigated in order to select three representative years with below average, average and above average annual rainfall depths. Rainfall events corresponding to each year were selected, where the rainfall depth was more than 2mm. The 2mm threshold was selected as the minimum rainfall depth that generates runoff from impervious surfaces (Boyd et al., 1994).
For the assessment of stormwater quality, measured inflow stormwater quality in Florida (as reported in UoF, 2011) was compared with the stormwater quality measurements from two monitoring programs undertaken by Queensland University of Technology (QUT). One study involved the monitoring of four residential catchments in the Gold Coast region. The other came from monitoring of the car park at the Direct Factory Outlet (DFO) shopping centre at Brisbane Airport.
Both monitoring programs used automatic sampling equipment, and the collected stormwater runoff samples were tested for primary stormwater quality parameters, which includes TSS, TN and TP. Further details of the Gold Coast catchment monitoring program are available in Goonetilleke Figure 2. Scatter plot of rainfall duration vs. rainfall depth for et al. (2005). the SEQ and Florida rainfall events.
WATER AUGUST 2014
RESULTS AND DISCUSSION COMPARISON OF FLORIDA AND SOUTH-EAST QUEENSLAND RAINFALL CHARACTERISTICS
Assessment of rainfall characteristics in SEQ was based on a total of 207 rainfall events selected from three representative years: 1999, 2004 and 2005. These three years were selected from an investigation of long-term rainfall trends (see Figure 1). This investigation was based on the hypothesis that the characteristics of rainfall events that influence stormwater quality can differ during a relatively dry year and a relatively wet year. Accordingly, the differences in rainfall event characteristics due to long-term weather conditions can be accommodated by selecting representative rainfall years for each specific period. As shown in Figure 1, the three selected representative years include a relatively wet year (1999), an average wet year (2004) and a relatively dry year (2005) in terms of the annual rainfall depth. Moreover, the selected years are also representative in terms of the number of wet days per calendar year. The primary rainfall characteristics that influence stormwater quality are rainfall depth, duration, average intensity and maximum intensity (see, for example,
55
Technical Papers
Figure 3. Scatter plot of rainfall duration vs. maximum six-minute rainfall intensity for 207 SEQ and 25 Florida discrete rainfall events. Liu et al., 2012). Accordingly, rainfall depth, rainfall duration and maximum sixminute rainfall intensity were taken as the appropriate parameters for comparison. Average intensity was not included due to its direct relationship with rainfall depth and duration. The primary rainfall characteristics for the 25 Florida rainfall events given in the UoF (2011) report, and the selected 207 SEQ rainfall events, were initially compared using a graphical method. The scatter plot for rainfall duration and rainfall depth is given in Figure 2. Figure 3 shows the scatter plot for rainfall duration and maximum six-minute intensity. As evident in Figure 2 and Figure 3, the Florida rainfall events do not cluster separately from the SEQ events. Rather, the Florida events are randomly scattered within the envelope created by the SEQ events. This suggests that the monitored
Florida rainfall events are similar to the events that occur in SEQ in terms of their primary characteristics. To assess the statistical similarity of the primary rainfall parameters between Florida and SEQ, the sampling approach referred to as the Bootstrap Method was adopted (Efron and Tibshirani, 1993). Under the assumption of independent data points, a large number (1,000) of random sample data sets, each of 25 data points in size, were drawn from the SEQ rainfall data pool and compared with the characteristics of the 25 events from Florida. When these sample data sets were drawn, one data point at a time was selected and recorded each time (i.e. sampling with replacement). The selected data point was put back into the SEQ data pool prior to selecting the next data point, so that the size of the data pool remains constant prior
It could be concluded that the rainfall parameters are similar if the summary statistics for the Florida data fell within the 95% bootstrap intervals. Table 1 shows that all rainfall parameters are similar except for two minor discrepancy correlations, as the corresponding summary statistics for Florida are well within the lower and upper bootstrap interval of SEQ events. These results strengthened the previous conclusion of similarity of the monitored Florida rainfall events with typical SEQ events based on their primary rainfall characteristics (i.e. rainfall depth and duration). COMPARISON OF AVERAGE RECURRENCE INTERVAL DATA
In an event-based rainfall analysis, Liu et al. (2012) found that the temporal pattern of rainfall exerts a significant influence on stormwater quality. Accordingly, it was concluded that the comparison of rainfall events should go beyond the comparison of primary characteristics and incorporate the rainfall temporal patterns in the analysis. However, as noted by Egodawatta et al. (2007), pollutant wash-off is significantly influenced by the maximum rainfall intensity, where high kinetic energy in raindrops can dislodge
Table 1. Statistical similarity of primary rainfall parameters for SEQ and Florida. Parameter
Lower bound on 95% bootstrap interval
Upper bound on 95% bootstrap interval
Summary statistics for Florida data
Within the 95% bootstrap interval or not
Mean rainfall depth
7.97
20.51
15.25
Yes
Mean rainfall duration
94.08
197.76
135.04
Yes
Mean rainfall maximum intensity
18.85
41.55
41.40
Yes
Standard deviation of rainfall depth
6.14
27.08
13.37
Yes
Standard deviation of rainfall duration
66.18
214.15
160.36
Yes
Standard deviation of rainfall maximum intensity
14.49
47.81
29.30
Yes
Correlation between rainfall depth and duration
0.02
0.88
0.61
Yes
Correlation between rainfall depth and maximum intensity
0.31
0.89
-0.06
No
Correlation between rainfall duration and maximum intensity
-0.38
0.40
0.51
No
AUGUST 2014 WATER
STORMWATER TREATMENT
to selection of each point. For each sample data set, summary statistics were calculated, creating 1,000 summary statistics for each parameter of interest. These formed distributions of typical parameter values that would be observed if a sample size of 25 were taken from SEQ. These distributions (or, more specifically, the 95% bootstrap intervals) were then compared to the summary statistics calculated from the Florida data in order to determine how likely or similar they might be.
56
STORMWATER TREATMENT
Technical Papers event. This confirms that the vast majority of events that occurred during the average rainfall year of 2004 are frequent events. The rainfall events for Florida are also scattered within the same envelope in which the SEQ events are distributed. Therefore, it can be Figure 4. Temporal variations of intensity-duration curves concluded that the for rainfall events in Florida and SEQ. curves representing Florida events are a relatively higher fraction of pollutant similar to the SEQ events. Figure 4 shows load from catchment surfaces. Therefore, that only one Florida rainfall event is those characteristics that represent the greater than the SEQ 1 year ARI. variation in rainfall intensities in relation to its maximum and average values needed to be investigated. For comparison, intensity-frequencyduration curves were derived according to the procedures outlined in Australian Rainfall and Runoff (AR&R) (1998). The rainfall durations considered were 6, 10, 15, 30, 60, 120, 180 and 360min, the same as specified in AR&R (1998). It was postulated that the slope of the intensityfrequency-duration (IFD) curves provide insight into the variations in rainfall temporal patterns. The IFD plots for the 25 Florida rainfall events reported by UoF (2011), and for the 69 events for the SEQ average rainfall year (2004), are presented in Figure 4. Figure 4 also gives the 1-year and 2-year ARI (average recurrence interval) curves for SEQ, for comparison. As shown in Figure 4, all the SEQ rainfall events considered are below the 1-year ARI envelope, except for one
COMPARISON OF FLORIDA AND SOUTH-EAST QUEENSLAND STORMWATER QUALITY CHARACTERISTICS
The performance of a stormwater treatment device can show characteristics that are specific to the stormwater quality profile at the installation site. These stormwater quality characteristics are influenced by the surrounding soil characteristics, site management and landscaping practices such as fertiliser usage. Given these factors, it was important to compare the measured stormwater quality in the UoF (2011) study with stormwater quality characteristics typical of SEQ. Comparisons of event mean concentration values (EMC) using box and whisker plots are given in Figure 5 and Figure 6. In the box and whisker plots, the box represents the middle
Figure 5. Comparison of TSS concentrations (TSS – total suspended solids; FLO – Florida; DFO – Direct Factory Outlet; GC – Gold Coast) and event mean concentration values (EMC).
WATER AUGUST 2014
50% of data, which is bound by the first (Q1) and third (Q3) quartiles. Whiskers represent data outside the middle 50%. Further, dots represent the outliers, which are at least 1.5 times the interquartile range less than Q1 and greater than Q3. Figure 5 shows the comparison of measured total suspended solids (TSS) concentrations, while Figure 6 shows a comparison of measured nutrient concentrations in SEQ and Florida. Figure 5 shows that TSS concentration ranges measured in Florida are generally within the range of concentrations observed in the SEQ study areas. Furthermore, from Figure 6 it is evident that TN concentrations are also closely comparable between Florida and SEQ study areas. However, in the case of TP, the concentrations observed in Florida are relatively higher compared to the SEQ study areas. The similarities in TSS and TN concentration ranges between the Florida and SEQ study areas suggest that TSS and TN removal should not be very different if the treatment device was installed in SEQ. However, its performance in relation to TP removal needs further investigations. Additionally, the statistical similarity of the stormwater quality parameters between Florida and SEQ was assessed similarly to the comparison of their rainfall characteristics. A non-parametric one-way ANOVA, referred to as the Kruskal-Wallis test, was used to compare independent data sets from Florida and SEQ monitoring programs. For this comparison, the data set from the Gold Coast monitoring program was preferred over the data set from the monitoring program at the DFO.
Figure 6. Comparison of nutrient concentrations (TP – total phosphorus; TN – total nitrogen) and mean concentration values (EMC).
57
Technical Papers
Table 2. Statistical similarities of stormwater quality parameters for SEQ and Florida. TSS
TN
TP
p value
p value
p value
0.0306
0.0392
2.99E-09
Accept H0
Accept H0
Reject H0
Florida-Gold Coast Accept/Reject the null hypothesis at 1% significance level
This was due to the fact that TSS and TN concentration ranges obtained from the Gold Coast study were more consistent with the Florida study (see Figure 5 and Figure 6). Furthermore, the Gold Coast monitoring program was a long-term program (over six years) that encompassed a relatively large geographical area when compared to the monitoring program at the DFO. The Kruskal-Wallis test computes a chi-square statistic with a statistical significance measured by the p-value, facilitating hypothesis testing. The test was performed by choosing the null hypothesis (H0): Florida and Gold Coast stormwater quality measurements have the same distribution. The alternative hypothesis (HA) is that Gold Coast stormwater quality characteristics are different from the Florida measurements. The p-values obtained from this analysis are given in Table 2. As shown in Table 2, H0 for TSS and TN can be accepted, while H0 for TP is rejected at the 1% significance level. As such, results of the statistical analysis further strengthens the conclusions derived from the box plot comparison of stormwater quality parameters given in Figure 5 and Figure 6.
CONCLUSIONS The analysis undertaken to assess the treatment performance of a stormwater treatment device in Florida to SEQ conditions consisted of two phases. Initially, the characteristics of the Florida rainfall events were compared with typical rainfall characteristics for SEQ. For the assessment of inflow stormwater quality, measured data from the Florida study was compared with the stormwater quality measurements from two monitoring programs previously undertaken by QUT. Rainfall depth, rainfall duration and maximum six-minute rainfall intensity for Florida and SEQ rainfall events were initially compared using scatter plots.
The cluster pattern of the Florida events suggests that primary characteristics of these events are similar to the events that occur in SEQ for average, and above and below average rainfall years. A more detailed analysis of the statistical similarity of the primary rainfall parameters between SEQ and Florida strengthened this conclusion. Additionally, the analysis of intensityfrequency-duration curves and rainfall temporal patterns confirmed that the SEQ rainfall events selected from the average rainfall year (2004) were similar to the monitored Florida events. In the case of stormwater quality, measured data for Florida was initially compared with data derived from two SEQ monitoring programs using boxplots. TSS and TN concentration ranges for the Florida study were similar to the SEQ data. However, the concentrations of TP observed in the Florida study were relatively high compared to the SEQ study areas. These conclusions were further strengthened by a rigorous statistical analysis of the stormwater quality parameters. Based on the similarities in TSS and TN concentration ranges between Florida and SEQ, it was concluded that their removal performance would not be very different if the treatment device was installed in SEQ. However, its performance in relation to TP removal needs further investigation. The methodology presented could be extended to a comparison of other water quality parameters.
THE AUTHORS Dr Prasanna Egodawatta (email: p.egodawatta@qut. edu.au) is a Senior Lecturer in Water/Environmental Engineering at Queensland University of Technology. His main areas of research include urban hydrology, stormwater quality and water and environmental systems modelling.
Buddhi Wijesiri (email: buddhisrinath.wijesiri@ student.qut.edu.au) is a Doctoral Researcher at Queensland University of Technology. His current research entails uncertainty analysis in relation to urban stormwater pollutant processes. Professor Ashantha Goonetilleke (email: a.goonetilleke@qut.edu. au) is a professor in Water/ Environmental Engineering at Queensland University of Technology. His main areas of research include urban hydrology, water quality and integrated water resources management.
REFERENCES Al Bakri D, Rahman S & Bowling L (2008): Sources and Management of Urban Stormwater Pollution in Rural Catchments, Australia. Journal of Hydrology, 356, 3–4, pp 299–311. AR&R (1998): Australian Rainfall and Runoff – A Guide to Flood Estimation, Vol 1, Engineers, Australia, Barton, ACT. Boyd MJ, Bufill MC & Knee RM (1994): Predicting Pervious and Impervious Storm Runoff from Urban Drainage Basins. Hydrological Sciences Journal, 39, 4, pp 321–332. Clark SE & Pitt R (2012): Targeting Treatment Technologies to Address Specific Stormwater Pollutants and Numeric Discharge Limits, Water Research, 46, 20, pp 6715–6730. Efron B & Tibshirani R (1993): An Introduction to the Bootstrap, Chapman and Hall, New York, London. Egodawatta P, Thomas E & Goonetilleke A (2007): Mathematical Interpretation of Pollutant WashOff from Urban Road Surfaces Using Simulated Rainfall, Water Research, 41, pp 3025–3031. Goonetilleke A, Thomas E, Ginn S & Gilbert D (2005): Understanding the Role of Land Use in Urban Stormwater Quality Management. Journal of Environmental Management, 74, pp 31–42. Liu A, Goonetilleke A & Egodawatta P (2012): Taxonomy for Rainfall Events Based on Pollutant Wash-Off Potential in Urban Areas. Ecological Engineering, 47, pp 110–114. UoF (2011): TARP Field Test Performance Monitoring of a Jellyfish® Filter JF4-21, Engineering School of Sustainable Infrastructure and Environment (ESSIE), University of Florida, Gainesville, Florida.
AUGUST 2014 WATER
STORMWATER TREATMENT
FLO – concentrations measured in Florida monitoring program GC – concentrations measured in Gold Coast monitoring program
Dr James McGree (email: james.mcgree@qut.edu.au) is Senior Lecturer in Statistics at Queensland University of Technology. Predominantly a Bayesian statistician, he has a research focus in the optimal experimental design and analysis of experiments.
58
Technical Papers
CAN YOU AFFORD MANAGED AQUIFER RECHARGE? Application of a decision support system for the staged implementation of ASR schemes in the city of Adelaide A Moyse, R Martin
INTRODUCTION
Stormwater recycling via ASR schemes is currently undertaken in the Adelaide metropolitan area by local governments, water utility companies and sporting facilities. ASR presents a convenient and space-efficient water storage option for harvesting winter stormwater flows through urban catchments so that they can then be used for irrigation during summer. Proponents of stormwater recycling ASR schemes may have a range of motivations including: security of irrigation water supply during dry weather; community recognition for positive environmental stewardship; use of otherwise too saline groundwater;
and appropriate ASR well completion, several other critical elements such as water capture, treatment infrastructure, automation electronics and large water transfer pipelines are typically required. A reliable decision support system is required in order to navigate the necessarily detailed investigations underpinning successful ASR scheme implementation.
The following case study outlines the application of a decision support system developed by Australian Groundwater Technologies (AGT) for the staged implementation of ASR schemes. Described below are feasibility investigations into stormwater recycling ASR for the irrigation of public spaces within the City of Mitcham in metropolitan Adelaide.
The decision support system developed by AGT is based on the 2009 Australian MAR Guidelines, but has been expanded upon reflecting AGTâ&#x20AC;&#x2122;s extensive practical field experience in management and monitoring of ASR schemes.
THE AGT DECISION SUPPORT SYSTEM FOR ASR SCHEME IMPLEMENTATION
The current Australian MAR Guidelines feature a four-stage ASR scheme implementation process: Stage 1 entails the collection of available data and an entry level scheme viability assessment; Stage 2 includes major technical investigations (water quality sampling, hydrogeological studies, catchment studies, basic groundwater modelling and geochemical evaluation) and risk assessment steps; Stage 3 involves scheme construction and residual risk assessment; and Stage 4 involves project operation and verification through ongoing operational management.
Stormwater recycling ASR schemes are complex engineered structures that require careful investigation and design. While such schemes ultimately rely on suitable aquifers for storage
PHOTO: ADRIAN HILL
MANAGED AQUIFER RECHARGE
South Australia, the driest state in the driest inhabited continent, is a world leader in stormwater harvesting and reuse through managed aquifer recharge (MAR) â&#x20AC;&#x201C; specifically the use of dedicated water wells for both stormwater injection and subsequent recovery, known as aquifer storage and recovery (ASR).
and cost savings compared to irrigation with mains water. This being said, the implementation of a successful and financially viable stormwater recycling ASR scheme is typically a complex undertaking requiring experienced specialists from multiple disciplines.
City of Mitcham in Adelaide, South Australia.
WATER AUGUST 2014
Unlike the Australian MAR Guidelines the proposed decision support system features eight stages. The general structure of the two decision support systems is similar, but the AGT system isolates some critical elements of the Australian MAR Guidelines into discrete stages and incorporates preliminary business case development during the feasibility assessment investigations. The preliminary business case development is deliberately placed before extensive and expensive field
59
Technical Papers Some of the Patawalonga Basin catchments, particularly that of the Sturt River, contain engineered drainage channels through urbanised areas. Interconnected underground stormwater drainage is extensive throughout the City of Mitcham.
DESKTOP FEASIBILITY ASSESSMENT The key outcome of the high-level desktop feasibility assessment undertaken was to identify geographic regions (â&#x20AC;&#x2DC;priority zonesâ&#x20AC;&#x2122;) within the City of Mitcham that were favourable for stormwater recycling ASR infrastructure. A priority zone was considered to be a convergence of sufficient water use demand, appropriate stormwater harvesting conditions and viable storage options (tank storage was considered where aquifer storage was not viable for otherwise prospective schemes).
investigations such that budget for these activities can be best biased towards schemes with favourable long-term financial projection results. One of the key aims of the proposed decision support system for ASR implementation is to ensure that wellintentioned stormwater recycling ASR infrastructure does not emerge as a significant unfunded financial liability in the long term. The general objective of the additional stages in the system is to provide flexible project management options. If necessary, multiple opportunities are provided at which the scheme proponent can terminate the ASR project at an early stage before extensive capital is outlaid. The following case study describes elements within the first two stages of the AGT decision support structure. These two stages are the first of four discrete feasibility investigation phases and include desktop feasibility assessment, conceptual ASR scheme layout and preliminary business case development.
BRIEF BACKGROUND TO CITY OF MITCHAM PHYSIOGRAPHY AND STORMWATER CATCHMENTS The City of Mitcham includes two main physiographic regions: the lower elevation Adelaide Plains zone to the north-west and the Adelaide Hills zone to the south and south-east (Figure 1). These two zones are marked by the regional uplift of the Western Mount Lofty Ranges associated with the EdenBurnside fault that runs south-west to north-east through the Council area. A little over two-thirds of the Council area is in the Adelaide Hills zone (Figure 1). The City of Mitcham is located within the Patawalonga surface water basin, draining generally westwards towards the coast with an area of 235km2. The upper catchment area of the Patawalonga Basin contains the catchments of Brownhill Creek, Keswick Creek and Sturt River; with the coastal margins of the Basin containing the Adelaide Airport drain, local Patawalonga and coastal catchments.
Stormwater harvesting conditions were assessed by way of estimated runoff volumes calculated using catchment boundaries and land use characteristics. Rural catchment areas were assigned lower runoff coefficients than urbanised areas, as is standard for catchment studies. Some surface water drainages also had annual gauged flow; in these cases gauged annual flow generally compared favourably with calculated runoff estimates. Harvestable stormwater was taken to be half of the annual estimated runoff volume. The investigation of surface water quality was limited to available data, and was identified as a key knowledge gap for feasibility assessments. Available surface water quality data was compared to relevant guideline values (SA Environmental Protection Authority (Water Quality) Policy (EP (WQ) P) 2003; and Australian and New Zealand Environment and Conservation Council (ANZECC) 2000 80% threshold). Potentially favourable locations for aquifer storage of harvested stormwater
AUGUST 2014 WATER
MANAGED AQUIFER RECHARGE
Figure 1. City of Mitcham boundaries, physiographic regions and stormwater recycling priority zones.
Water use demand was considered for Council irrigation of public spaces and for third party use such as educational facilities and industrial use. Estimated Council irrigation demand was comprised of current metered irrigation use and use for spaces that would be irrigated if water was available. Annual irrigation demand for public recreation spaces not currently irrigated was estimated based on land area, as was education facility demand. Potential industrial use was identified but could not be accurately estimated.
60
Technical Papers
MANAGED AQUIFER RECHARGE
were established through review of published reports and a detailed review of water well details available through the SA Department for Environment, Water and Natural Resources (DEWNR) WaterConnect online database. The data review was aimed at records likely to relate to aquifers that were potentially favourable for ASR storage; focusing primarily on well yield and groundwater salinity reported during drilling. Two main aquifer systems exist within the City of Mitcham that offer potential for ASR storage of harvested stormwater: confined aquifers in Tertiary-age marine sediments of the St Vincent Basin and confined fractured rock aquifers in Neoproterozoic age meta-sedimentary basement rock. The two systems are generally exclusive and are associated with the two main topographic zones within the Council boundary: Tertiary aquifers in the north-west Adelaide Plains region, bounded by the EdenBurnside fault (running south-west to north east); and fractured rock aquifers in the Adelaide Hills region of the Council associated with the Western Mount Lofty Ranges (Figure 1). Six priority zones were identified within the Council boundary; four were located in the Adelaide Plains region or at the base of the Adelaide Hills, and two were located in the Adelaide Hills zone proper. The locations of these priority zones are presented in Figure 1. These priority zones were then used to set the geographic boundaries of conceptual ASR scheme layouts for stormwater recycling.
CONCEPTUAL ASR SCHEME LAYOUTS OF STORMWATER RECYCLING The aim of each conceptual ASR scheme layout was to establish a range of implementation options within the priority zones identified from the desktop feasibility assessment. These conceptual scheme layouts featured Council use of recycled stormwater, with and without third-party use. First-order construction cost estimates were also undertaken for the conceptual layouts such that each implementation option could be compared in terms of estimated cost per annual delivery volume of recycled stormwater. Multiple scheme conceptual layouts were developed within each priority zone, each with estimated water use demand and potential stormwater harvest volumes. Conceptual ASR scheme layouts varied in annual delivery volume
WATER AUGUST 2014
capacity, based on which public spaces were included and whether third-party use was included or not.
employed tank storage were typically associated with lower annual stormwater recycling volumes.
In total, 16 conceptual scheme layouts were developed across the six priority zones, with annual stormwater recycling volumes ranging from 11 megalitres per year (ML/year) up to 298 ML/year. The lower volume capacity scheme layouts were generally associated with tank storage.
The estimated cost per annual delivery volume of recycled stormwater was a function of both the construction cost estimate and the annual delivery volume for each conceptual scheme layout. Conceptual scheme layouts that featured third party use of recycled stormwater were generally estimated to be cheaper per ML/year compared to Councilonly implementation options, although the total construction cost was more expensive. This was due to the increased total annual recycled stormwater volume when third-party use was included, but applied only to those that utilised aquifer storage. Tank storage conceptual layouts with third-party use were generally more expensive than council-only alternatives in terms of $/ML/year due to increased costs associated with greater tank storage requirements.
All conceptual scheme layouts featured stormwater harvest points and volumes, treatment points and likely processes, storage points and main pipeline routing for the movement of harvested stormwater to use locations. Where aquifer storage appeared feasible, an effort was made to include wells that the City of Mitcham already had access to. Scheme conceptual layouts did not include reticulation system design within water use locations, nor were pipeline routes ground-truthed or optimised for existing subsurface infrastructure that may already be present. The first-order construction cost estimates developed for each conceptual scheme layout had an assumed potential final cost variation of Âą40%. These cost estimates were based on specific elements of each conceptual layout (number of harvest points, treatment type, diameter and length of main pipeline, number of ASR wells required) but were kept generalised and high level in nature, in keeping with the level of detail in the conceptual scheme layouts. Detailed engineering design and associated costing was considered inappropriate for the early stages of feasibility investigations due to the time and expense involved, particularly considering preliminary business case assessments had not yet been undertaken. First-order construction estimates ranged from $140,000 to over $4,000,000. Conceptual layout construction cost estimates were particularly sensitive to the length of main pipeline included, with those layouts featuring greater third party use typically requiring greater pipeline length. Construction cost estimates for conceptual scheme layouts that employed tank storage were typically substantially cheaper than those employing aquifer storage; this was due to less complex and less expensive investigation and construction requirements. As previously described, those scheme conceptual layouts that
While the estimated cost per annual delivery volume ($/ML/year) allowed the comparison between conceptual scheme layouts, the better financial comparison is between preliminary business cases for each conceptual scheme.
PRELIMINARY BUSINESS CASE ASSESSMENT (FINANCIAL PROJECTION MODELLING) A preliminary business case assessment was undertaken for seven conceptual ASR scheme layouts selected by the City of Mitcham. These business case assessments entailed financial projection modelling that established the long-term projected average unit cost for recycled stormwater in terms of dollars per kilolitre ($/kL) and enabled the comparison of this cost to irrigation with mains water. Financial projection models were detailed, capturing construction costs based on conceptual scheme layouts and ongoing operation expenses determined from AGTâ&#x20AC;&#x2122;s substantial operational experience of ASR schemes. Financial projection models ran for a period of 35 years and included construction finance repayments, ongoing operational expenditure, periodic capital expenditure, depreciation of capital assets, and taxation allowances. All modelled ongoing operational and management costs were indexed at 3% per year to reflect generalised cost increases in line with the annual increase in the consumer price index, published by
61
Technical Papers the Australian Bureau of Statistics. The term and interest rate of construction finance was supplied by the City of Mitcham and reflects realistic finance terms available to Council. The projected unit cost of recycled stormwater for Council use was calculated on an annual basis for all production expenses in a given year within the model. The projected unit water cost became substantially cheaper once construction finance had been repaid and only operational expenses were to be covered. Mains water cost was also included in the financial projection model and incremented from 2013 rates at 3% per year. This projected mains water cost served as an annual comparison to projected recycled stormwater unit costs and enabled the projection of longterm cost differences between mains water and recycled stormwater use for irrigation over 35 years.
Another key outcome of preliminary business case investigations was that conceptual ASR scheme layouts with annual recycling volume less than 50 ML/year emerged as more costly in the long term when compared to mains water irrigation. Aquifer-storage conceptual layouts that included third-party supply of recycled stormwater were projected to be substantially more financially attractive compared to the Council-only alternatives. This was due to both the income generated by water sales and the overall larger stormwater recycling volumes that annual production expenses could be spread over. A clear drawback of conceptual scheme layouts that included third-party supply was that the favourable financial modelling results hinged on the necessity to secure legal water supply contracts for the modelled third-party supply volumes. Of the Council-only conceptual scheme layouts modelled (both aquifer and tank storage options), only two emerged as
SUMMARY AND CONCLUSION The above case study generally describes the application of the first two stages within the AGT decision support structure for stormwater recycling ASR scheme implementation to the City of Mitcham, metropolitan Adelaide. These two stages are the first of four discrete feasibility investigation phases and feature desktop feasibility assessment, conceptual ASR scheme layouts and preliminary business case development. The proposed decision support system is based on the 2009 Australian MAR Guidelines but has been expanded upon reflecting extensive practical field experience in monitoring and management of ASR schemes. A key element of the approach is to incorporate preliminary business case assessment prior to typically expensive field investigations. The objective of the additional stages in the AGT decision support system is to provide flexible project management options and multiple opportunities at which the scheme proponent can terminate the ASR project, before extensive capital is outlaid. The desktop feasibility assessment highlighted six priority zones for potential ASR scheme implementation within the City of Mitcham for the irrigation of public spaces. A total of 16 conceptual ASR scheme layouts were developed for the identified priority zones, with both Council-only and additional third party use of recycled stormwater. Preliminary business case development was undertaken for seven conceptual scheme layouts and revealed that the projected long-term water cost for lowervolume, cheaper-to-implement schemes was generally more expensive than irrigation with mains water. Larger volume conceptual schemes (above 50 ML/year) were generally projected to save money in the long term compared to mains water irrigation, with those that included thirdparty use projected to be substantially more financially attractive than Councilonly schemes. A clear drawback of conceptual ASR scheme layouts featuring
third-party use is the requirement for legally binding water supply agreements and the establishment of Council as a commercial water supplier. Of the original 16 conceptual ASR scheme layouts developed within the City of Mitcham priority zones, only two Council-only schemes emerged with favourable preliminary business cases. The larger of these two schemes included all irrigation sites of the smaller scheme. The application of the expanded decision support system for ASR scheme implementation has allowed the City of Mitcham to establish which conceptual scheme layouts are most favourable, based on rigorous feasibility investigations and financial projection modelling. The early stages of the AGT support system are far less expensive to implement than detailed field investigations and scheme construction, thus cost-effectively allowing the best allocation of financial resources for future works as determined by Council.
ACKNOWLEDGEMENT The Authors would like to acknowledge the cooperation of the City of Mitcham in the preparation of this case study. This case study is not an endorsement of Australian Groundwater Technologies by the City of Mitcham.
THE AUTHORS Aidan Moyse (email: amoyse@agwt.com.au) is a Hydrogeologist with Australian Groundwater Technologies (AGT) in Adelaide. AGT has specialist skills in the delivery, monitoring and management of stormwater harvesting and re-use aquifer storage and recovery (ASR) systems. Aidan is engaged in both technical and reporting aspects of ASR scheme implementation. Russell Martin (email: rmartin@agwt.com.au) is a Principal Hydrogeologist and the General Manager of AGT. He is one of the pre-eminent authorities on the implementation of ASR in Australia, responsible for the successful implementation and management of numerous ASR schemes. Under his management the South Australian Department for Water Resources jointly received a United Nations acknowledgement in 2001 for ASR research undertaken in conjunction with the CSIRO.
AUGUST 2014 WATER
MANAGED AQUIFER RECHARGE
A general overview of financial projection modelling results is that lower volume tank-storage conceptual scheme layouts were substantially more expensive than aquifer storage conceptual layouts in the long term. This was primarily due to the ratio between ongoing operational expenditure and the annual volume of recycled stormwater to be produced.
having projected long-term savings when compared to mains water irrigation. The larger of these two schemes encompassed the other, essentially leaving one of the original 16 conceptual ASR scheme layouts that had a favourable preliminary business case assessment.
62
Technical Papers
USING URBAN STORMWATER AND AQUIFERS OR RESERVOIRS FOR NONPOTABLE AND POTABLE SUPPLIES Key outcomes from the MARSUO research project P Dillon, D Page, G Dandy, R Leonard, G Tjandraatmadja, J Vanderzalm, K Rouse, K Barry, D Gonzalez, B Myers
MANAGED AQUIFER RECHARGE
ABSTRACT A project titled ‘Managed Aquifer Recharge for Stormwater Use Options’ (MARSUO) has investigated the public health, economic and public acceptance aspects of a number of different options for using stormwater via managed aquifer recharge and/or via reservoirs. This evaluated the quality of stormwater generated in the City of Salisbury, the treatment requirements and risk management measures necessary to assure safe water quality for public open space irrigation, third-pipe reticulation to homes and for potential drinking water supplies. The project also assessed biofilms and water quality impacts in distribution systems, public acceptance, and the economics and environmental impacts of options. An existing stormwater harvesting facility at Parafield in the City of Salisbury, South Australia, was chosen as the primary site for evaluation. Data from harvesting operations enabled assessment of their performance for non-potable uses and determination of additional treatments, preventive measures and costs of achieving drinking water standards. Studies of satellite sites in Australia, Singapore, China and India were undertaken to compare stormwater quality and treatment requirements for potable use and allow interpretation of the relevance of results from Salisbury. This paper provides an overview, with examples of results to give the Australian water industry a taste of the information now available for public use.
Mount Lofty Ranges Natural Resources Management Board, the former United Water International, SA Water Corporation, University of Adelaide and University of South Australia in work that has just concluded with 10 reports and 13 journal papers to date, with many more papers to come. The outputs include a series of pioneering documents on the use of stormwater, including the first published: risk assessment for potable use of stormwater in accordance with the Australian Guidelines for Water Recycling (Page et al., 2013a); risk management plans for non-potable and potable use (Page et al., 2013a; Vanderzalm et al., 2014a); stormwater harvesting audit (Stevens, 2014); economic assessment of stormwater use options including assessment of greenhouse gas emissions and an ecosystems services framework method to evaluate environmental benefits and costs of stormwater harvesting (Dandy et al., 2014); surveys of public acceptance of use of stormwater for potable as well as non-potable supplies (Mankad et al., 2013b); studies of the effect of harvested stormwater quality on pipe biofilms and corrosion in distribution systems and consequent potential impacts on reticulated water quality (Tjandraatmadja et al., 2014); and an international review of stormwater quality and treatment requirements for achieving potable supplies (Vanderzalm et al., 2014b).
INTRODUCTION
LAND USE AND STORMWATER QUALITY
Between 2011 and 2014, CSIRO partnered with the National Water Commission and the Goyder Institute for Water Research in South Australia, together with the City of Salisbury,
The City of Salisbury, a local government authority in the northern suburbs of Adelaide, is acknowledged as a leader in stormwater harvesting using wetlands and aquifer storage and recovery (ASR).
WATER AUGUST 2014
Recovered water from the aquifer is fed into a ring main and used for public open space irrigation, industrial water supplies and to dilute salinity of recycled water in a non-potable supply to households throughout the suburb of Mawson Lakes. The locations and land uses of the catchments for the Salisbury stormwater harvesting systems are shown in Figure 1. The Parafield stormwater harvesting facility located at Parafield Airport collects primarily from the Parafield stormwater catchment and is supplemented by pumping stormwater from the Cobbler Creek catchment. Parafield Airport has a mean annual rainfall of 438mm (1972–2009). The Parafield catchment has an area of 1,590 ha, 73% of which is urban, and produces a mean runoff of approximately 1300 ML/yr. It contains residential, industrial and commercial areas, major rail and road routes, and small horticultural and livestock grazing properties. The eastern-most catchment on Figure 1 is an open catchment in the lower Mount Lofty Ranges that supplies the Little Para Reservoir and water treatment plant that feed into Adelaide’s drinking water mains. The reservoir is less than 12km by road from the Parafield harvesting facility, and is 35m higher in elevation. Each catchment in Figure 1 was assessed for potential sources of stormwater quality hazards. This risk assessment was conducted based on the key water quality hazard classes as defined by the MAR guidelines (NRMMC-EPHC–AHMC, 2006): (1) pathogens (viruses, protozoa and bacteria); (2) inorganic chemicals; (3) salinity and sodicity; (4) nutrients; (5) organic chemicals; (6) turbidity and particulates; and (7) radionuclides. Myers et al (2013) found through modelling and measurement that flow times of
63
Technical Papers other technologies with similar pathogen removals would also be required. This study found log removals required for pathogens in stormwater were 3 to 4 logs less than required for secondarytreated sewage effluent (Figure 2). Monitoring of water leaving the wetland revealed that detected physical and chemical parameters met drinking water quality criteria, with the occasional exception of iron, turbidity and colour. Following recovery from the aquifer in aquifer storage and recovery (ASR) wells the 95th percentile of these parameters exceeded the drinking water guidelines (NHMRC-NRMMC, 2011). There was also one isolated, unexplained detection of Campylobacter in recovered water, after the standard initial purging of an ASR well, but indicator organisms were not detected.
solutes in the catchment were too short to depend on catchment protective measures alone, so water treatment must be relied on to assure water is fit for its intended uses. Endpoints considered were human health, the environment (including the storage aquifer and irrigated areas) and operational infrastructure (harvesting, distribution and irrigation systems). The most significant hazard expected and found was pathogenic microorganisms. Human pathogens generally enter stormwater through sewage overflows and leakages. Within the Parafield and Cobbler Creek catchments from 2006 to 2010, the five-year average annual number of sewer overflows per 100km of sewer main were 16.5 and 17.5 respectively (United Water). These overflow rates may be compared with 7 to 9.8 for the whole Adelaide metropolitan area from 2003 to 2007 (NWC, 2008) and 14.5 to 50, which is considered moderate to high for Australian water utilities (NRMMC-EPHCNHMRC, 2009a). Other pathogen sources are from land grazed by livestock.
RISK ASSESSMENT The water quality evaluation of pathogens was the most comprehensive of any found on urban stormwater in Australia or internationally and allowed quantitative microbial risk assessment of the log removals required for uses of harvested stormwater with different levels of human exposure (Figure 2, adapted from Page et al., 2013a). The data requirements and resulting values were determined and affirmed by the MARSUO Water Safety Expert Panel. Based on Australian Guidelines for Water Recycling (NRMMC-EPHC-AHMC, 2006), for public open space irrigation, exposure controls alone are sufficient to meet health-based targets. For third-pipe systems, treatments such as chlorination and ultraviolet light (UV) (for Cryptosporidium) are necessary to meet these targets. Ozone, membranes or other technologies are equally applicable. For drinking water supplies, to meet health-based targets would require aquifer treatment validated at 4-log removal, then disinfection with UV and chlorination. In the absence of validation of aquifer treatment, ultrafiltration or
STORMWATER QUALITY AT SATELLITE SITES Stormwater quality data were also assessed from the following sites to allow interstate and international comparisons: • City of Orange, NSW • City of Mount Gambier, SA • Fitzgibbon research site, Brisbane, Qld (within Urban Water Security Research Alliance) • City of Singapore, Singapore (following storage in a reservoir) • City of Jinan, China • City of Haridwar, India • International Stormwater Best Management Practices (BMP) Database including data from various locations within the US, New Zealand and Taiwan (www.bmpdatabase.org/, WERF). Considering the variety of climates and catchments embraced in the study, the evaluated stormwater quality data
AUGUST 2014 WATER
MANAGED AQUIFER RECHARGE
Figure 1. Catchment land uses related to stormwater harvesting and reuse schemes. Land use data sourced from DPLG (2011) and ABARES (2012) (from Page et al., 2013a).
Median iron levels were in excess of drinking guidelines for ASR-recovered water at Parafield, Kaurna Park, Paddocks and Unity Park. In addition to the proposed disinfection (UV and chlorination) iron, turbidity and colour removal would be achieved either through media filtration or microfiltration to meet drinking water guidelines. In the event of direct recovery to the mains distribution system, microfiltration, pH adjustment and fluoridation would be required in addition to chlorination and UV. Further work would be needed to mitigate variability of water quality that may otherwise impact customers.
64
Technical Papers at sites where the limit of detection was sufficiently low. However, this polyaromatic hydrocarbon is strongly sorbed and is expected to be removed by either aquifer passage or filtration.
RISK MANAGEMENT
MANAGED AQUIFER RECHARGE
Figure 2. Log10 removals required for safe use of stormwater for three types of use, based on pathogen data from this study and default values from Australian Guidelines for Water Recycling for stormwater and sewage (adapted from Page et al., 2013a). (Each log removal reduces pathogen numbers by 90%, eg. 2 logs reduces numbers by 99%.)
Based on the risk assessment, a risk management plan was developed in consultation with City of Salisbury, SA Water and the MARSUO Water Safety Expert Panel for the existing non-potable uses of stormwater (Page et al., 2013b). This provides a template that could be considered by organisations elsewhere intending to harvest stormwater. An audit of the Salisbury stormwater harvesting operations with respect to the risk management plan has since been undertaken and is publicly available (Stevens, 2014). A potable use risk management plan was developed (by Vanderzalm et al., 2014a) for the City of Mount Gambier, one of the satellite sites evaluated in the project. There, urban stormwater is intentionally recharged through drainage wells to an aquifer that replenishes Blue Lake, the source of drinking water supply.
IMPACTS ON DISTRIBUTION SYSTEM
Figure 3. Total iron in stormwater from various catchments (from Vanderzalm et al., 2014b). The drinking water guidelines (NHMRC-NRMMC, 2011) and long-term (LTV) and short-term (STV) irrigation values (ANZECC-ARMCANZ, 2000) are shown for comparison. from all catchments, although variable, were surprisingly similar from a risk assessment perspective. Hazards with 95th percentile values exceeding the drinking water guideline values at Parafield (iron, turbidity, colour and faecal indicators) also exceeded guidelines at all other sites for which data were available. Similarly, hazards with 95th percentile concentrations below the drinking water guidelines at Parafield, such as other metals (e.g. zinc), salinity (electrical conductivity) and nutrients, including nitrate, were also below the guidelines at all sites.
WATER AUGUST 2014
The Parafield stormwater quality data were not atypical of stormwater quality for the parameters that could be assessed. Figure 3 is an example illustrating total iron concentrations in stormwater from various catchments. In this box plot, upper (and lower) dots are 95th (and 5th) percentiles, end bars are 90th and 10th percentiles and boxes show 75th, 50th (median) and 25th percentiles, where detections allow. Only one organic chemical, benzo(a)pyrene, was found at concentrations exceeding drinking water guideline values in stormwater
A study on pipe biofilms and water quality was also undertaken to assess the likelihood of water quality changes and impacts on infrastructure maintenance. Two identical experimental buried pipe rigs were operated for 10 months, each containing coupons of copper, cement lining and PVC pipe (Tjandraatmadja et al., 2014). Wetland and aquifer-treated stormwater was run in one rig and the other contained a reference water of dechlorinated mains water. Water quality in the stormwater rig had greater variability than the baseline water, but there was no statistically significant difference in the sediment deposited (as dry mass) on coupons in the two rigs. Biofilm abundance and diversity were studied on coupons in both rigs. There were indications of sloughoff of biofilm from both rigs. Potential pathogens were present within biofilm in both rigs, suggesting that a disinfectant residual would be required in both water types to reduce the risk of water supply contamination from dislodged biofilm material.
PUBLIC ACCEPTANCE An assessment of public acceptance of treated stormwater for third-pipe systems and drinking water supplies was conducted through focus groups
65
Technical Papers
Table 1. Most preferred option for increasing Adelaideâ&#x20AC;&#x2122;s future water supply (from Mankad et al., 2013). Treated stormwater use
Taking more River Murray water
Desalination
Treated stormwater
Non-potable use
22.2%
17.7%
60.1%
Potable use
23.1%
10.7%
66.1%
Total
22.7%
14.2%
63.1%
Note: Non-potable use n = 604, Potable use n = 614, Total N = 1218
due to the trust the community holds for water suppliers and regulators to provide safe water over the long term. Knowledge of more common stormwater terms appeared to contribute to acceptance of stormwater via managed aquifer recharge. This suggests familiarity with certain basic concepts may contribute to increased acceptance, but a high degree of technical knowledge is not needed. If stormwater is intended to be harvested for potable use or for residential, non-potable use, an appropriate public information and consultation process would be needed for the project.
ECONOMIC ASSESSMENT
The estimated levelised costs in 2012/13 (accounting for capital and operating cost) of each option are shown in Figure 5. Costs include estimates of water treatment and management costs (determined from the risk assessment), and account for direct costs of salinity but exclude environmental costs and benefits. Levelised costs that include existing infrastructure are thought to be a better general indication for stormwater harvesting elsewhere, but costs will be site-specific. Excluding the existing infrastructure (as sunk costs) gives a better picture for local decision makers. Figure 5. Levelised cost of the various options, including and excluding the capital costs of existing infrastructure. LRMC is Long Run Marginal Cost (adapted from Dandy et al., 2014). and two web surveys (Mankad et al., 2013a, b). Participants indicated that both potable and non-potable stormwater use options were acceptable, based on the information they received.
River Murray, for future augmentation of Adelaideâ&#x20AC;&#x2122;s water supply (Table 1). However, participants were not willing to pay more for stormwater, particularly if it was of non-potable quality.
Participants also indicated a preference for stormwater over alternative water supply options, namely desalination and purchasing more water from the
If treated stormwater were to be used for drinking water systems, there was a preference that government-owned water utilities undertake such projects,
The benefits, however, differ among relevant entities. The existing water utility sees least benefit in new supplies of all types, having already invested in water security measures, and sees its benefits constrained to the operating costs of the mix of alternative supplies. The benefits for the state are normally regarded as the long-run marginal cost, but also depend on environmental benefits of stormwater harvesting that have yet to be fully quantified. The benefits for local government are highest
AUGUST 2014 WATER
MANAGED AQUIFER RECHARGE
Figure 4. Twelve options for augmenting water supplies.
The net benefits of each of 12 options were evaluated for the Parafield site by Dandy et al. (2014). They were considered at one site for the harvesting, treatment and storage of stormwater via aquifers and or dams. Uses include public open space irrigation, third-pipe systems and drinking water supplies, and include blending with recycled water for nondrinking uses. Each option is shown in Figure 4 as a string with dots indicating the water quality-modifying components present in that option. The treatments selected in each option were tailored to meet the water quality requirements for the relevant uses.
66
Technical Papers for all entities reflecting savings on the price of existing retail supplies.
MANAGED AQUIFER RECHARGE
For the options considered at the study site involving 370 to 1100 ML/y stormwater use, including costs of existing infrastructure, the least costs were found to be those for public open space irrigation, followed by drinking water supply augmentation. The most costly were third-pipe residential supplies, especially for retrofitting existing residential areas. Public open space irrigation and industrial use had the lowest costs, ranging from $1.31/ kL (option 4), involving blending with recycled water from the Bolivar Sewage Treatment Plant to $1.57/kL (option 2), without blending. Drinking water supply augmentation costs ranged from $1.47/kL (option 10 â&#x20AC;&#x201C; pumping stormwater to the Little Para Reservoir (without aquifer) for storage, treatment and reticulation through mains) to $2.51/kL (option 9 â&#x20AC;&#x201C; supply to mains via a localised treatment plant with comprehensive risk management systems). Residential third-pipe options started at $2.74/kL (option 8G), where stormwater is blended with recycled water from Bolivar STP. That is, the treatment costs for producing potable water from stormwater are less than the costs of constructing a separate nonpotable water distribution system. When costs of existing infrastructure were excluded from the analysis, levelised costs were substantially lower, e.g. as low as $0.42/kL for public open space irrigation (option 2). Environmental costs and benefits were evaluated using an ecosystems services framework, in categories of provisioning services (e.g. marine biodiversity and recreation), amenity (wetlands and coastal water clarity) and regulation services (e.g. greenhouse gas emissions and flood mitigation). Where data were available items were estimated quantitatively, otherwise qualitatively. At the Parafield study site the benefits were similar for all options and did not help to discriminate between options. Due to lack of information on some items, and to specific conditions relevant to this site, the magnitude of quantitatively enumerated impacts was relatively small in comparison with estimated costs. With more information, and for other water harvesting designs or in other locations, it is expected that environmental benefits could be considerable (Kandulu et al. in press).
WATER AUGUST 2014
Table 2. Relative costs and demands of different stormwater use options for the Parafield stormwater harvesting system. Supply type P.O.S. irrigation and industrial 3rd pipe household Drinking
Levelised cost
Demand
Treatment
Distribution
Total
low
low
low
moderate
high
high
low
high
low
low-moderate
high
The outcomes of the net benefits analysis at Parafield are generalised in Table 2. Demand relates to that in the area that can be met most economically by a distribution system. Local factors may result in different relative costs and demands in other locations.
CONCLUSIONS The MARSUO project was designed to assess risks associated with different stormwater use options and determine how they can be managed, to inform assessment of the net public benefits of potable and non-potable options, and to determine the level of community support for these options. This information was used to brief the SA Government on all these matters in late 2013. Each aspect of the project has developed methods that are transferable to other catchments and this is demonstrated at satellite sites where there are suitable data. From a national perspective, the MARSUO project demonstrates the potential application of stormwater for a wide range of future uses. It suggests that drinking water uses be considered in addition to public open space irrigation, industrial use and third-pipe supplies. The study shows, through an example, that treatment costs to augment drinking water supplies may be cheaper than the costs of establishing separate nonpotable water distribution systems to households. The project demonstrates the value of aquifer storage to increase the capturable volume, and its potential to provide water treatment that, alone or in combination with reservoirs, reduces the unit costs of supply. It was also found that drivers for sectors of the water industry can be quite different and the best commercial stormwater use options for an individual entity are not necessarily the optimal use for the city as a whole. This may therefore invoke loss of opportunity benefits and creation of under-utilised assets unless such benefits and risks are identified. Policies are necessary to align commercial opportunities with best and most efficient use of the resource. Current
low
governance arrangements do not provide an economic framework in which the whole water sector picture is considered and, as a result, opportunities can be missed. The MARSUO project shows that the technical difficulties and water safety aspects are manageable with adequate water sampling and analyses, using established processes under the National Water Quality Management Strategy. The next steps are to improve efficiency by developing validation of treatment processes during aquifer storage, deepen the national stormwater quality database and develop processes that enable timely financial integration, leveraging stormwater and water supply assets so that the highest valued projects are supported. It is intended that the project will inform stormwater policy in Australia, allow the best uses of stormwater to be identified for projects of different types and scales, and that the methods and results will provide tools, templates and examples to simplify the safe and efficient uptake of this resource. A summary report (Dillon et al., 2014) contains a more detailed overview and all reports are available at the Goyder Institute website: goyderinstitute.org/index.php?id=20.
ACKNOWLEDGEMENTS This paper was produced as part of the Managed Aquifer Recharge and Stormwater Use Options (MARSUO) project. This national project was supported by the National Water Commission, the Goyder Institute for Water Research, CSIRO Water for a Healthy Country Flagship Research Program, City of Salisbury, Adelaide and Mount Lofty Ranges Natural Resources Management Board and (formerly) United Water International. The Authors are grateful to Chris Davis, Chair of the Steering Committee and its members, and members of the Water Safety Expert Panel, David Cunliffe, Don Bursill, John Radcliffe and Tavis Kleinig for their review and advice. We also thank all members of the research team and the many people who have assisted the research through the Technical Committee.
67
Technical Papers THE AUTHORS Dr Peter Dillon (email: peter.dillon@csiro.au) is a Research Engineer at CSIRO. His primary research area is scientific and governance aspects of water recycling of stormwater and treated sewage via aquifers. Dr Declan Page is a Research Scientist with CSIRO. His areas of research include risk assessment, water quality, and treatment and management of water recycling via natural treatment systems. Professor Graeme Dandy recently retired as Professor of Civil and Environmental Engineering at the University of Adelaide. He is the 2014 AWA Water Professional of the Year.
Grace Tjandraatmadja is a Research Scientist with CSIRO, evaluating integrated water and wastewater services and transition strategies for more sustainable and climate resilient urban water services. Dr Joanne Vanderzalm is a Research Scientist with CSIRO, assessing the biogeochemical processes induced during water reclamation and reuse via Managed Aquifer Recharge. Karen Rouse is an Urban Water Research Leader (previously for CSIRO Water for a Healthy Country Flagship) committed to improving the management of urban water resources. Karen Barry is a Research Projects Officer in Managed Aquifer Recharge, assessing water quality in catchment and groundwater management and clogging issues arising from aquifer storage.
Dr Baden Myers is a Research Engineer at the Centre for Water Management and Reuse at the University of South Australia.
REFERENCES ANZECC & ARMCANZ (2000): Australian and New Zealand Guidelines for Fresh and Marine Water Quality: Volume 1 The Guidelines, NWQMS Doc 4. Canberra. www.environment.gov.au/ system/files/resources/53cda9ea-7ec2-49d4-af29d1dde09e96ef/files/nwqms-guidelines-4-vol1.pdf. Dandy G, Ganji A, Kandulu J, Hatton MacDonald D, Marchi A, Maier H, Mankad A & Schmidt CE (2014): Managed Aquifer Recharge and Stormwater Use Options: Net Benefits Report. Goyder Institute for Water Research Technical Report 14/1, 179p. goyderinstitute.org/index. php?id=20 Dillon P, Page D, Dandy G, Leonard R, Tjandraatmadja G, Vanderzalm J, Rouse K, Barry K, Gonzalez D & Meyers B (2014): Managed Aquifer Recharge and Stormwater Use Options: Summary of Research Findings. Goyder Institute for Water Research, Technical Report 14/x goyderinstitute.org/index.php?id=20 (in press). Kandulu J, Hatton-Macdonald D & Connor J (in press). Ecosystem Services in Urban Water Investment Evaluation. Journal of Environmental Management (in press). Mankad A, Walton A, Alexander K & Leonard R (2013a): Dimensions of Public Acceptance for Stormwater and Managed Aquifer Recharge. Proc. AWA Conf. Ozwater’13, Perth, May 2013. Mankad A, Walton A & Leonard R (2013b): Public Attitudes Towards Managed Aquifer Recharge and Stormwater Use in Adelaide, 2013. Goyder Institute for Water Research. Goyder Institute for Water Research Technical Report 13/10, 87p. goyderinstitute.org/index.php?id=20 Myers B, Pezzaniti D & Gonzalez D (2013): Hydrological Modelling of the Parafield and Cobbler Creek Catchment for Hazard Analysis Planning, MARSUO Milestone Report 2.2. Goyder Institute for Water Research Technical Report 13/3, 130p. goyderinstitute.org/index.php?id=20 NHMRC & NRMMC (2011): Australian Drinking Water Guidelines. NWQMS Document No 6. Canberra. www.nhmrc.gov.au/guidelines/ publications/eh52 NRMMC, EPHC & AHMC (2006): Australian Guidelines for Water Recycling: Managing Health and Environmental Risks. NWQMS Document No 21. www.environment.gov.au/topics/water/ water-quality/national-water-quality-managementstrategy#guidelines. NRMMC-EPHC–NHMRC (2008): Australian Guidelines for Water Recycling: Managing Health
and Environmental Risks (Phase 2). Augmentation of Drinking Water Supplies. NWQMS Document 22. www.environment.gov.au/topics/water/ water-quality/national-water-quality-managementstrategy#guidelines NRMMC-EPHC–NHMRC (2009a): National Water Quality Management Strategy. Australian Guidelines for Water Recycling: Managing Health and Environmental Risks (Phase 2) Stormwater Harvesting and Reuse. NWQMS Document 23. www.environment.gov.au/topics/ water/water-quality/national-water-qualitymanagement-strategy#guidelines NRMMC-EPHC–NHMRC (2009b): Australian Guidelines for Water Recycling: Managing Health and Environmental Risks (Phase 2) Managed Aquifer Recharge. NWQMS Document 24. www.environment.gov.au/topics/water/waterquality/national-water-quality-managementstrategy#guidelines Page D, Gonzalez D, Dillon P, Vanderzalm J, Miotlinski K, Vadakattu G, Toze S, Sidhu J, Torkzaban S & Barry K (2013a): Managed Aquifer Recharge and Stormwater Use Options: Public Health and Environmental Risk Assessment Final Report. Goyder Institute for Water Research Technical Report No 13/17, 214p. goyderinstitute.org/index.php?id=20 Page D, Gonzalez D, Naumann B, Dillon P, Vanderzalm J & Barry K (2013b): Stormwater Managed Aquifer Recharge Risk-Based Management Plan, Parafield Stormwater Harvesting System, Stormwater Supply to the Mawson Lakes Recycled Water Scheme for Dual Reticulation and Unrestricted Municipal Irrigation, and Stormwater Supply for Industrial Uses and Restricted Municipal Irrigation. Goyder Institute for Water Research Technical Report 13/18, 106p. goyderinstitute.org/index.php?id=20 SA Department of Environment Water and Natural Resources (2009): Water for Good. www. environment.sa.gov.au/about-us/our-plans Stevens D (2014): Audit of the Parafield Stormwater Harvesting and Managed Aquifer Recharge System for Non-Potable Use Against the Stormwater Risk-Based Management Plan. Goyder Institute for Water Research Technical Report 14/x, 47p. goyderinstitute.org/index. php?id=20 (in press). Tjandraatmadja G, Gonzalez D, Barry K, Kaksonen AH, Vanderzalm JV, Puzon G, Sidhu J, Wylie J & Goodman N (2014): Investigation of Stormwater Impact on Water Quality and Distribution Infrastructure. Goyder Institute for Water Research Technical Report No. 14/8 (in press). Vanderzalm J, Page D, Dillon P, Lawson J, Grey N, Sexton D & Williamson D (2014a): A RiskBased Management Plan for Mount Gambier Stormwater Recharge System: Stormwater Recharge to the Gambier Limestone Aquifer. Goyder Institute for Water Research Technical Report 14/7 (in press). Vanderzalm J, Page D, Gonzalez D, Barry K, Toze S, Bartak R, Qu Shisong, Weiping W, Dillon P & Lim MH (2014b): Managed Aquifer Recharge and Stormwater Use Options: Satellite Sites Stormwater Quality Monitoring and Treatment Requirements. Goyder Institute for Water Research Technical Report 14/10 (in press).
AUGUST 2014 WATER
MANAGED AQUIFER RECHARGE
Dr Rosemary Leonard is a Research Scientist with CSIRO, applying her research expertise to community attitudes to water supply, community wellbeing and climate change.
Dennis Gonzalez is a Research Projects Officer in management of water recycling via natural treatment systems using risk assessment and GIS mapping of catchments.
68
Technical Papers
FROM WASTEWATER TO RESOURCE: A TECHNOLOGICAL ROADMAP An overview of a strategic research collaboration between Veolia Water and Sydney Water Y Poussade, J Bernard, D Seccombe, H Bustamante
ABSTRACT This paper provides an overview of a strategic research collaboration between Veolia Water (VW) and Sydney Water (SW). It is aimed at delivering scenariobased asset planning simulations on three case studies based on existing wastewater treatment plants (WWTPs), with a primary focus on long-term resource recovery options. Outputs for each scenario were compared in terms of material mass balance, energy efficiency, biosolids volume and selected operational expenditure data (chemicals, energy and biosolids). The outputs from this study have been used by Sydney Water to inform its facility blueprint reports in primary plants that aim at developing more detailed costs and benefits analyses, including capital expenditures, for the most interesting scenarios.
WASTEWATER TREATMENT
INTRODUCTION Wastewater treatment is likely to experience major changes in the next 10 to 20 years, due to the combination of stringent regulatory, environmental and economic constraints. This provides an opportunity to rethink the role of the current WWTP, with the aim of moving from a cost centre towards the next generation “bio-refinery” as a revenue centre. To realise this paradigm shift, the first milestone is to achieve WWTP energy self-sufficiency through the concept of “consume less and produce more energy”. The second milestone will be to enhance the extraction of co-products from wastewater, whether they be clean water, electricity, heat, chemicals, phosphorus or other valuable materials. For each WWTP, the optimal process lines and mix of co-products produced on-site will differ depending on the local context. Therefore, Veolia Water is proposing a tailor-made, long-term roadmap approach that relies on a portfolio of unit treatment or extraction
WATER AUGUST 2014
processes that will be gradually assembled into the WWTP, in order to build the targeted bio-refinery. In order to develop technological roadmaps suitable for a wide range of WWTPs, contexts and drivers, the technical department of VW has developed a modelling and simulation tool called OCEAN. OCEAN allows comparative analysis of different process trains in terms of plant energy and material mass balances. SW is already recovering water and energy (heat and electricity) at many of its WWTPs and is beneficially reusing 100% of its biosolids (Pramanik et al., 2012). Through an existing research collaboration with VW, a project was initiated in July 2012 to assess current and future opportunities for additional resource recovery by using OCEAN for the simulation of various process train scenarios on three existing WWTPs. This paper presents the approach taken and results obtained during this project, as well as some key conclusions and perspectives for VW and SW.
MATERIALS AND METHODS THE WASTEWATER TREATMENT PLANTS
The project focused on two large primary coastal plants located at North Head and Malabar, and one full tertiary water recycling plant located at Rouse Hill. North Head and Malabar are SW’s largest WWTPs, treating about 350 and 480 megalitres per day (ML/d) respectively. Wastewater is treated by high-rate primary treatment and discharged to the ocean via a deepwater outfall located three to four km from the shoreline. Primary sludge is thickened and sent to anaerobic digesters. The digested biosolids are dewatered by centrifugation before being trucked away for beneficial
reuse (mainly agricultural land application). Biogas generated in the digesters is used in a Combined Heat-Power (CHP) generation unit and excess biogas is flared. The heat and electricity are used onsite to preheat the sludge fed to the digesters and operate electrical equipment. At North Head, there is also a micro-turbine on the ocean outfall to recover additional electrical energy from the treated water discharged. The plant also comprises a small membrane bioreactor (MBR) for producing onsite process water. By comparison, the Rouse Hill plant, which is located in Sydney’s northwest sector, is much smaller, with an average flow of 13.5 ML/d. Wastewater treatment, however, is more advanced, with full biological nutrient removal and tertiary chemical phosphorus precipitation followed by granular media filtration. The treated water is either discharged after chlorination and dechlorination to a wetland basin, or further processed with UV and super chlorination disinfection for recycling via a dual pipe reticulation scheme. The waste-activated sludge is thickened and stabilised in an aerobic digester, before dewatering by centrifugation. Final biosolids (30 wet t/d at 19% dry solids) are trucked away for land application beneficial reuse. There is currently no energy recovered at Rouse Hill, so all energy needs have to be met by grid electricity purchase. VEOLIA’S PROCESS SIMULATION TOOL: OCEAN
OCEAN is a static model using inhouse process design and operational knowledge, and an existing database of case studies. For each plant studied, plant design data and measured performance data are required to build the OCEAN model. The model runs a mass balance on materials
69
Technical Papers such as carbon, nitrogen or phosphorus and is then calibrated based on the differences between the predicted and measured biosolids production, biogas generation and energy consumption for set effluent quality targets (see Figure 1).
Table 1. Models calibration. North Head Final biosolids volume Electrical energy use Electrical energy produced
Figure 1. OCEAN tool inputs and outputs. Historical data gathered over 12 months from 2011 and 2012 were used to calibrate the models. An additional thorough sampling program was conducted over three weeks on the large coastal plants to obtain supplementary data on inter-process streams and develop a more accurate mass balance. STRATEGIC SCENARIOS DEVELOPMENT
For each case study, several scenarios were simulated using OCEAN covering various levels of wastewater treatment, using the existing wastewater and biosolids treatment processes as a baseline and developing towards a resource recovery bio-refinery.
For each scenario, various options were investigated for processing the biosolids post-digestion: a) onsite greenhouse solar drying (only at Rouse Hill WRP); b) onsite thermal drying; c) on-site wet air oxidation (WAO). A range of resource recovery options were investigated, covering carbon, either in the form of energy (methane in biogas) or poly-hydroxy-alkanoates (PHA) as precursors for bio-plastics, phosphorus as magnesium ammonium phosphate (MAP), nitrogen as ammonium sulphate, solids (either as dried biosolids or inorganic solids from WAO), and water (as very high-quality water with possible uses
Rouse Hill
OCEAN (tDS/d)
13.5
24.0
5.7
Gap (%)
-6.8%
1.9%
-5.3%
OCEAN (MWh/d)
123.5
78.6
22.5
Gap (%) OCEAN (MWh/d) Gap (%)
-9.8% 51.1 -6.4%
-2.6% 54.8 5.5%
0.2% 0 NA
to be determined). Figure 2 provides a high-level overview of the various process trains simulated in this study. It is important to note that, for some of these options, data could be sourced from extensive full-scale experience, while for others data was generated based on Veolia’s internal research program and have not been validated at full-scale or in the Australian context. Considering the strategic nature of the project, the large number of scenarios evaluated, and the fact that there is no fullscale reference on municipal wastewater treatment for some of the processes studied, capital expenditure was excluded from the scope of this project.
KEY RESULTS MODELS CALIBRATION
Table 1 shows the model values obtained in OCEAN for each of the plants, and the differences in the actual historical data gathered from the plants for final biosolids volume, electrical energy consumption and production. For the purpose of this project, a gap of less than 10% between measured and calculated data was considered as satisfactory. ENERGY PERFORMANCE
Energy performance of the WWTPs was assessed by calculating the level of electrical self-sufficiency defined, by the amount of electricity produced, divided
by the amount of electricity required to operate the plants. Maintaining heat self-sufficiency (for the operation of the anaerobic digesters and thermal driers where required) was given priority over the production of combined heat-power via cogeneration units. There is currently no energy recovery at Rouse Hill as the waste-activated sludge is stabilised by aerobic digestion. Figure 3 presents some of the most interesting simulation results obtained at Rouse Hill. By converting the aerobic digestion process to a mesophilic anaerobic digester (MAD) coupled with a cogeneration unit, adding side-stream anaerobic ammoniaoxidising (Anammox) treatment on the sludge dewatering effluent, and by optimising the aeration in the biological reactors, the plant could reach 16% of electricity self-sufficiency. This could be doubled to 33% self-sufficiency by restoring primary settling (PST). Importantly, there would be no need for carbon addition in the biological denitrification stage, partially thanks to the side stream Anammox treatment of ammonia. Finally, a mainstream Anammox process installed downstream from a primary settling tank with coagulation (PSTpc) could theoretically further increase this to about 42% electrical self-sufficiency. At North Head, heat and electricity are recovered by cogeneration of the biogas from anaerobic digestion and
Figure 2. Overview of resource recovery pathways simulated in the case studies.
AUGUST 2014 WATER
WASTEWATER TREATMENT
The scenarios were developed through discussions with VW experts and SW staff to consider current drivers and possible future developments for resource recovery. Some scenarios were based on existing ‘off-the shelf’ technologies, while others were more oriented towards future development of technologies and based on preliminary data and estimates from VW’s internal research.
Malabar
70
Technical Papers
Figure 3. Potential for energy recovery at Rouse Hill (solar drying option only).
WASTEWATER TREATMENT
a mini-hydroturbine is also recovering energy from the ocean outfall, totalling just over 50MWh of electricity per day on average. However, the plant has a high-energy demand due to a large raw sewage pumping lift to the inlet. Eighty per cent (80%) of the plant electricity use is associated with these pumps, resulting in an electrical self-sufficiency level of about 40%. Figure 4 illustrates some of the most interesting simulation results obtained at North Head. The level of electrical self-sufficiency could rapidly be increased to 58% by adding another cogeneration unit to reduce the biogas flared to about 5% of the volume produced. Adding a coagulant to the primary settling tank (PSTpc) converted to lamellar settlers, and converting the mesophilic digesters to thermophilic (TAD), would further increase the level of electrical selfsufficiency to 68%, while improving the overall wastewater treatment (capture rate for suspended solids increasing from 34% to 48%; COD from 21% to 50%; and total phosphorus from 0% to 64%). This level of electrical self-sufficiency could almost be maintained (64%) with biological treatment if a combination of upfront anaerobic reactor (such as an upflow anaerobic sludge blanket – UASB – reactor) was used in combination with a short sludge age anaerobic/oxic process (A/O). This would further improve treatment to 93%, 96% and 53% removal of suspended solids, COD and total phosphorus respectively. At Malabar, the current level of electrical self-sufficiency is about 70%, based on the biogas produced by anaerobic digestion of the primary sludge, and a lower electricity demand compared to North Head. All the resource recovery scenarios assessed
WATER AUGUST 2014
Figure 4. Potential for energy recovery at North Head (WAO option only).
on this plant impacted negatively to different degrees on the current electrical self-sufficiency, as a result of the introduction of either more advanced wastewater treatment, or more advanced biosolids treatment processes. The addition of wet air oxidation (WAO) to dramatically reduce biosolids, combined with chemically enhanced primary treatment, resulted in a slight decrease in electrical self-sufficiency (down to 65%). This is because WAO requires on-site generation of oxygen, but this would be a preferred option compared to truck deliveries due to the lower impact on neighbouring communities. By comparison, the option of thermal drying of biosolids had a more severe impact, reducing the electrical self-sufficiency to 41% as biogas had to be diverted from the cogeneration unit to the dryer’s boiler. Adding a short sludge age anaerobic/oxic biological treatment step and thermal hydrolysis of the biological sludge resulted in a further reduction of electrical self-sufficiency to 57%, but the quality of treated effluent was much higher, with 95% removal of suspended solids and COD, and 60% of total phosphorus. However, the most promising process combination for energy-efficient wastewater treatment (mainstream anaerobic reactor + Anammox) was not studied for this plant. This process combination could potentially result in a level of electrical self-sufficiency
equal to or higher than the current 70% value, with a better quality of treated water and smaller volumes of final solids. BIOSOLIDS BALANCE
SW is currently beneficially reusing 100% of the biosolids that it produces, either via agricultural land application, or composting. However, this requires long-distance transportation of the biosolids from the point of production to the point of use, usually in the range of 300 to 400km for the coastal plants, which results in high management costs. In addition, the biosolids outlet options are currently relatively limited and finding alternative markets could reduce cost and business risk for SW. Three options were considered for reducing the final volume of biosolids at Rouse Hill: on-site solar drying (targeting 70 to 76% final dry solids (DS) content), thermal drying (65 to 90% DS) and wet air oxidation (60% DS). On the coastal plants where space is a severe constraint, on-site solar drying was not considered as a feasible option. The options were tested in combination with the various scenarios studied for
Figure 5. Potential for energy recovery at Malabar (WAO option only).
71
Technical Papers
Table 2. Current biosolids production. WWTP Rouse Hill North Head Malabar
Final biosolids Wet weight (t/day)
Dryness (% DS)
Number of 30t trucks /day
30.2
19%
1.0
44
33%
1.6
89.7
27%
3.0
Finally, while the solar or thermally dried solids would still be considered as biosolids, the WAO final solids are more than 95% inorganic in content (Figure 8), which would result in opportunities in alternative reuse market applications such as raw material to be mixed with other materials for road or sewer construction, ceramic manufacturing or expanded clay material.
Mineralogical composition 1% 5%
5%
15%
34%
20% 20% Clay
Figure 6. Comparison of final biosolids management options.
Quartz Calcium carbonate Iron and calcium phosphate Feldspar Organic matter Soluble matter
Figure 8. Typical composition of WAO residue. OTHER MATERIAL RECOVERY OPTIONS
wastewater and biosolids treatment. Figure 6 shows final biosolids volumes and levels of electrical self-sufficiency depending on the three biosolids management options for the most basic scenarios studied at each plant. All options have the possibility to effectively reduce the final volume of biosolids significantly. WAO consistently resulted in the most significant reduction in final volume in spite of its lower final solids content (60%) compared to the other options. For instance, at Malabar the mass of wet solids would reduce from 90Â t/d to 21 and 35 t/d respectively with WAO and thermal drying, which represents 76% and 60% reductions in volume respectively, compared to current conditions. The energy balance was also in favour of WAO on all scenarios since the autothermal process does not require an extensive amount of external energy
(limited to the amount of energy required for onsite oxygen production) compared to thermal drying. In the Rouse Hill scenario presented in Figure 6, the biogas produced by anaerobic digestion of the biological sludge was not sufficient to maintain thermal selfsufficiency and additional natural gas had to be purchased to achieve the targeted 90% DS content from thermal drying. However, by restoring the primary treatment without chemical coagulation, and adding thermal hydrolysis on the biological sludge only before anaerobic digestion (Figure 7), the plant could achieve 100% thermal and 8% electrical self-sufficiency. In this scenario, the primary treatment could be restored with no need for external carbon addition in the biological nutrient removal process, thanks to side stream Anammox treatment of ammonia from the sludge dewatering effluent.
SW is already recovering treated wastewater from some of its plants such as Rouse Hill, where the water is used in a third-pipe reticulation system for domestic use after advanced tertiary treatment. Hypothetical scenarios were studied on the coastal plants to produce up to 100 ML/d of very high quality recycled water that may be used for alternative potable water supply in order to assess the impacts on the energy and material mass balances (results not presented here). In addition to energy and biosolids, the potential recovery of the following materials was investigated in various scenarios: â&#x20AC;˘ Phosphorus recovery as struvite or magnesium-ammonia-phosphate (MAP). MAP can be precipitated either directly in the digested sludge (Figure 9) or in dewatered sludge effluents by pH regulation and magnesium dosing. There are several full-scale references
AUGUST 2014 WATER
WASTEWATER TREATMENT
Figure 7. Thermal hydrolysis of biological sludge (LbioD configuration) at Rouse Hill.
72
Technical Papers the various scenarios studied was about 50 t/y using the current wastewater treatment process with anaerobic sludge digestion. This represents about 11% of the incoming phosphorus that could be recovered as MAP (Table 3).
Figure 9. MAP reactor from digested sludge.
Figure 11. Biopolymer and bioplastic produced from wastewater. 10), but there is growing interest in its application in the municipal market on sludge dewatering effluents.
WASTEWATER TREATMENT
Figure 10. Ammonia stripping contactors. in Europe, Japan and Northern America recovering struvite this way. Note that pure struvite contains 12.6% phosphorus and 5.7% nitrogen by weight, so a fraction of nitrogen is also recovered via struvite precipitation. • Nitrogen recovery as ammonium sulphate following ammonia stripping and sulphuric acid wash. This process is used in industrial wastewater treatment on ammonia-rich effluents (such as microelectronics wastewater – Figure
• Carbon recovery as poly-hydroxyalkanoates (PHAs) biopolymers that can be used in the manufacturing of bioplastics. This process is still under research and development and, while the concept has been proven (Figure 11), it has not yet been industrialised. Data for PHAs production assessment have been provided by Veolia’s internal research department. Because of its relatively small size, the Rouse Hill plant presented limited opportunities for the recovery of these materials in general. The maximum quantity of phosphorus that could be recovered from MAP precipitation from
Table 3. Potential for phosphorus recovery. Plant Rouse Hill North Head
Process changes
TP influent kg/d
P-PO4 recovered kg/d (%)
MAD + WAO
159
18 (11.2%)
WAO PSTpc + A/O + WAO 1
3,180
WAO Malabar
PSTpc1 + A/O + DLD2 +WAO
43 (1.3%) 285 (9%) 34 (0.9%)
3,640
335 (9.2%)
Notes: 1 – Scenarios with natural organic tannins not locking phosphates 2 – DLD is for Digestion / Lysis / Digestion – a continuous thermal hydrolysis process step was included in between 2 steps of anaerobic digestion
WATER AUGUST 2014
By comparison, and in spite of just relying on primary treatment, the opportunity for MAP recovery appears to be more significant on the coastal plants with 100 and 120 t/y of MAP that could be recovered from Malabar and North Head respectively. Adding a chemical coagulation step with natural organic tannins and a biological (anaerobic/ oxic) treatment step would significantly increase these values to 940 and 800 t/y at Malabar and North Head respectively. The use of tannins is interesting as it does not lock phosphates as ferric chloride does, thus allowing for higher recovery, but also because they can be digested during the anaerobic process, thus reducing the amount of residual solids and slightly increasing the level of biogas produced compared to metallic salts. Nitrogen recovery potential was assessed in a few scenarios at Rouse Hill, but considering the plant’s current set-up and the requirement for high nutrient removal, Anammox treatment of sludge dewatering effluents (rather than ammonia stripping) provided a better opportunity in the short term for reducing energy and potential carbon dosing needs for aeration and denitrification in the biological treatment step. On the coastal plants, larger volumes of ammonium sulphate solution could be recovered; even without secondary biological treatment, about 10t/d of ammonium sulphate solution at 400g/L could be recovered from the sludge dewatering effluent after struvite precipitation, which is equivalent to 850 kg/d of nitrogen or about 3–5% of the incoming load. Adding an anaerobic/oxic treatment step could increase this recovery rate significantly, as shown in Figure 13. The potential recovery of 1,000 tonnes per year of biopolymers was evaluated at North Head and Malabar on scenarios including an anaerobic/ oxic biological treatment step, as this process already acts as a biomass selector for the production of PHAs. The main impact of producing biopolymers is that it reduces the amount of carbon available for anaerobic digestion and biogas production, so there is an impact on the energy balance, as shown in Figure 14.
73
Technical Papers
Figure 12. Potential for MAP production. Therefore the value of recovering biopolymers in the future will have to be assessed in balance with the generation of energy, depending on market potentials. HIGH-LEVEL COMPARISON OF OPERATIONAL COSTS
Semi-quantitative operational costs, including costs for chemicals, energy and waste disposal, were evaluated in this study. Operational costs and potential revenues for the production of struvite, ammonium sulphate and biopolymers were excluded from the assessment as they would have been hypothetical and relatively marginal compared to other wastewater treatment or biosolids management costs.
Figure 13. Potential for ammonium sulfate production. Some significant cost savings could be realised on biosolids management and reuse on the three plants (Figure 15). At Rouse Hill operational costs could be further reduced by transforming the aerobic digestion process that is currently using 9â&#x20AC;&#x201C;10% of the total energy demand of the plant, into anaerobic digestion with cogeneration, and by optimising the aeration on the biological reactors (by installing oxygen sensors to control the aeration cycles, and upgrading the surface aeration turbines by more efficient subsurface systems). As expected, adding biological treatment to the coastal plants resulted in higher operational costs, primarily because of the important electrical needs for aeration.
Figure 15. High-level OpEx comparison.
CONCLUSIONS AND PERSPECTIVES This project looked at the potential for resource recovery at three existing wastewater treatment plants, starting with the current process trains and developing into theoretical future bio-refineries. Various process trains were simulated, using both established technologies and processes still in research and development, or not yet validated at full scale for the municipal wastewater market. Results were assessed in terms of energy balance, quantitative and qualitative biosolids production, resource recovery potential and highlevel operational expenditure comparison (limited to chemicals, energy and biosolids management costs). The results have highlighted some short-term opportunities for increasing energy recovery at North Head and Rouse Hill, and reducing biosolids management costs on all plants. Wet Air Oxidation
Figure 16. North Head OpEx comparison.
AUGUST 2014 WATER
WASTEWATER TREATMENT
Figure 14. Impact of PHAs production on electrical self-sufficiency.
However, relatively close operational expenditure data were obtained for scenarios where a mainstream anaerobic reactor or Anammox treatment was
simulated. This is illustrated in Figure 16, which provides a comparison of highlevel operational costs between primary only and primary plus secondary using a UASB reactor on raw wastewater at North Head.
74
Technical Papers and Thermal Drying can both provide a significant reduction of biosolids at much lower operational costs compared with dewatered digested biosolids. Wet Air Oxidation has the advantage of being auto-thermal, thus enabling a maximum of the biogas to be directed towards the cogeneration unit. It also results in a mainly inorganic residue (>97%) that offers an alternative market opportunity compared to biosolids. Additional opportunities may develop into the future depending on potential changes in regulation, technical developments, resource scarcity by increasing price of raw materials, and greenhouse gas emissions management policies.
WASTEWATER TREATMENT
Sydney Water has used the outputs from this project to inform its facility blueprint reports. The facility blueprint program considers detailed plant audits alongside strategic option costbenefit analyses to determine preferred treatment pathways into the future.
WATER AUGUST 2014
THE AUTHORS Yvan Poussade (email: yvan.poussade@veolia.com) is Research & Innovation Manager for Veolia Water Australia. He has 15 years of experience as a Chemical Engineer in research and development for water treatment and is in charge of a portfolio of research projects and collaborations with utilities, academic scientists and research centres. Jean-François Bernard (email: jean-francois. bernard@veolia.com) is Technical Manager Waste Water Treatment Process at Veolia Water Asia-Pacific. He has a Biochemistry Engineering Degree and 25 years of expertise in wastewater treatment and biosolids management. Django Seccombe (email: django.seccombe@ sydneywater.com.au) is a Senior Engineer working in the Servicing and Asset Strategy, Liveable City Solutions, at Sydney Water. He has a
degree in environmental engineering and has eight years of experience across the water industry. He is currently working in a technical role supporting and leading development of infrastructure strategy at Sydney Water. Dr Heri Bustamante (email: heri.bustamante@ sydneywater.com.au) is Principal Scientist Treatment in Business Strategy and Resilience Division, Sydney Water. Heri has more than 20 years of experience in the water industry. In his current role Heri is actively involved in collaborative research. This includes research on infrastructure (concrete sewer corrosion, advanced condition assessment of pressurised water mains) and treatment (biosolids research to reduce both odour and volume).
REFERENCES Pramanik A, Humphries R & Bustamante H (2012): Resource Recovery â&#x20AC;&#x201C; Challenges and Opportunities for the Water Industry. AWA & CSIRO Resource Recovery Seminar, Melbourne.
75
Technical Papers
APPLICATIONS FOR INTELLIGENT WATER NETWORK SYSTEMS Case studies to demonstrate how water utilities can use smart systems to tackle a diverse range of water issues J Sorbello, R Marck
ABSTRACT Utilities face many challenges today, from rising water costs to increasing customer expectations in relation to levels of service. Many innovative technologies and systems are increasing the amount of data available to water utilities to help address these issues. This sea of data requires unifying intelligent water network systems, such as the solution developed by TaKaDu, to aggregate information, provide actionable insights and clear benefits. For instance, the system’s leakage detection solution has successfully been trialled and deployed by three major water utilities in Australia. The real benefits in leakage reduction, avoided leakage and bursts, improved asset management and improvements in response times, can be measured and verified. The following case studies showcase how it is possible for an Australian water utility to tackle the challenges facing the water industry globally.
COMPLEX CHALLENGES Efficient water usage remains one of the most pressing global challenges facing society today. According to the United Nations, global water usage has been growing at more than twice the rate of population growth in the past century. By 2030, nearly half the global population could face water scarcity problems (United Nations, 2013). In the “sunburnt country” of Australia, water utilities have always looked for innovative ways to reduce loss and save water. Droughts, rising electricity costs and the need for more expensive water supply sources (such as desalination) have turned this long-running sustainability challenge into a tough, everyday economic reality.
During Australia’s most recent drought many utilities undertook pressure management or metering programs to divide, segregate and monitor their network (Australian Water Management Review, 2013). Some utilities are now embarking on smart metering trials. Lower costs, new types of instrumentation and remote telemetry (Boyle et al., 2013) are enabling utilities to collect more information than ever
before. However this ‘sea of data’ can be overwhelming, and understanding what’s important and what to address first can be quite difficult.
DESIGNING AN INTELLIGENT WATER NETWORKS SOLUTION Every day, water utilities generate an exceptional volume of raw data but, on average, 60% of this data goes unused simply because utilities do not have the capability to process the information quickly enough. As a result, a growing number of global water utilities are adopting a “smart” approach to improve the understanding, management and control of their water networks. An “Intelligent Water Network” (IWN) system provides utilities with the tools needed to achieve their quality, productivity and efficiency targets, while enhancing their level of customer service. IWNs comprise various different technologies ranging from sensors to communication technology and software tools.
INNOVATIVE SOLUTIONS CREATE MORE DATA Australia has been a hub of investment and innovation in the intelligent water networks space. Given the challenging
SMART SYSTEMS
Today, Australian water utilities face rapid population growth and the threat of drought, combined with ageing infrastructure (Water Services Association of Australia, 2012). At the same time, utilities must deliver good quality water to customers consistently,
efficiently and cost-effectively while quickly responding to any issues before they impact customers or the wider network (Skinner & Ewert, 2014). Preventing major failures is critical, and quick response times are crucial to minimising damage. According to SWAN’s (Smart Water Networks Forum) 2014 Global Utility Survey, customer service is the most powerful business driver for water utilities, cited by 76% of respondents as a top-three driver. In the same survey leakage was reported as the number one utility challenge area, being cited by 55% of respondents, while leakage reduction was seen as the key opportunity for improving network efficiency (SWAN, 2014). Thus, effective continuous network monitoring and management is becoming more important than ever.
Figure 1. The SWAN Technology Layer Model.
AUGUST 2014 WATER
76
Technical Papers operating environment this innovation has often been driven by necessity (Water Services Association of Australia, 2012 ). These solutions range from new meter technologies to high-level strategy assessments. Several trials have been undertaken of smart metering technologies, including Taggle and IBM in Townsville (IBM, 2013) and Itron in Kalgoorlie (Anda, Le Gay Brereton, Brennan and Paskett, 2013). Larger industrial complexes have also been involved in smart metering projects (Balberg and Hauber-Davidson, 2013). These systems have had success in reducing customer side leakage (typically 1–10 L/min range or up to 5 ML per annum), thereby reducing required water supply volumes. Since the leakage found is typically customer side, there is a revenue reduction for the utility, but a benefit in reducing delivered volumes and related energy or supply costs. As seen in Kalgoorlie, these measures can also defer substantial investment in water supply upgrades. More intuitive aggregation of information results can also result in large capital savings. Known issues and asset status can be used to make more efficient decisions on asset criticality and replacement as explored by Sydney Water and Jacobs SKM (Kane, Zhang, Lynch and Bendeli, 2014). Long-term capital deferments through either intelligent main replacement strategies or reduction in required supply through smart metering or other technologies can have a substantial capital expenditure benefit for a utility (Bendeli and Hersh, 2013).
SMART SYSTEMS
Efficient operations and improved asset performance with automatic adjusting valve systems can also help reduce operational expenditure. Derceto Aquadapt was trialled successfully at Unitywater (Derceto Aquadapt, 2012) and enabled Unitywater to more efficiently manage supply resulting in energy and cost savings, as well as increased productivity from their assets. New metering technologies have enabled utilities to gain a deeper insight into the water quality performance of their system (de Graaf et al., 2012). These new technologies can lead to deeper insights into issues that could potentially risk breaching Government health standards and even directly impact customers.
WATER AUGUST 2014
There have been substantial investments in research and development in IWN systems with a diverse range of approaches being taken. The challenge remains to correctly value and justify this investment or the cost of further development (du Plessis & Killen, 2013). The benefit from the triple bottom line return and strategic fit should be considered, but it is also important to measure the benefit from avoiding additional costs, risks, loss and capital expenditure. Although there are many innovative solutions created to improve network efficiency, there is still a need to tackle major inefficiencies not addressed by smart meters or replacement programs. With new technologies and information sources, it becomes even more critical to unify the varying information sources to create insights out of the ‘sea of data’ seen in the everyday operations of the utility. The time savings and deeper insights that become possible can enable faster responses to critical incidents and reduce the impact on customers.
A UNIFYING APPROACH TaKaDu’s approach to IWN is to utilise the information available from all systemised layers of technology to make informed assessments with actionable outcomes in near real time. The system combines the field data from instruments with spatial and asset information from GIS and asset management systems. Heuristic algorithms and statistical evaluation are used to learn the expected normal behaviour of the system and identify anomalies. The core functionality of the system is based around analytic engines that process the incoming data from the various instruments, detect when a statistically significant difference occurs and then classify this into a certain type. To achieve this the system first compares the incoming data to one of two predictions: the ‘Historic Prediction’ – a rolling historic average that gives weighting to recent months, and the ‘network prediction’ – a comparison to the weighted average of similar meters or zones in the network. The ‘Network Prediction’ at the time of each event automatically finds peer zones that have closely matched the performance of the zone in question for a period before the event. Then using factoring, a prediction is formed on the expected current behaviour (if the event had not occurred). By comparing to the performance of peers, changes due to weather, public
holidays and other behavioural changes will avoid the creation of false positives. After the system has determined if a statistically significant event has occurred by comparing the event to the predictions, the ‘Event Classification’ engine runs various tests on the event data to see if the observed data matches the simulated test of a burst, a breach, a meter fault or other types of event classifications. User feedback on the system in terms of event classification also provides further tuning and refinement using heuristic algorithms. By using statistical methods with learning algorithms the system adapts to changes in the network, in weather and in water consumption behaviour to cut down on false positives and provide clear actionable alerts about network inefficiencies. By aggregating and analysing this information, the system provides a powerful summary reporting on the performance of parts of the network over time to help inform operational, asset management and strategic planning decisions. As an evolving technology, the system has been guided by the needs of its clients to improve and offer new dashboards and views to summarise and aggregate information in new ways for various types of users within water utilities.
REAL WORLD EXAMPLES AND SAVINGS For more than three years, TaKaDu and its partner Jacobs SKM have been working with three utilities in Australia: Unitywater, Queensland Urban Utilities (QUU) and Yarra Valley Water. It is also used quite successfully across the world, including in Europe and in Latin America. By working with these utilities, the system has helped identify several key savings and benefits. Following are some recent case study examples from Australian utilities that demonstrate the capability and range of savings.
DETECTING HIDDEN LEAKAGE Early detection of abnormalities and leakage in a water distribution zone is an important part of intelligent water networks. Preventing a new leak from running for a long time represents an avoided increase in Non-Revenue Water (NRW). If it had not been resolved, the utility’s overall NRW would have increased and substantial amounts of would have been water lost.
77
Technical Papers At QUU in 2014, the system identified
run for years. This was detected in the
a large leak that occurred in parkland
first hour and resolved within 24 hours,
adjacent to the Brisbane River. Previously
and was recognised as an annualised
at QUU such leaks have been known to
avoided loss saving of 170 ML (Figure 2).
In 2013 at Yarra Valley Water, the system identified a large leak that was flowing underground and could not be detected otherwise for a long time. With the support of the system, Yarra Valley Water teams were able to locate the field by investigating the stormwater drainage. After closing off the leak, this was recognised as an annualised avoided loss saving of 265 ML (Figure 3).
DETECTING BACKGROUND LEAKAGE The detection of long-term trends and changes in distribution zone behaviour is carried out automatically by the system’s flow trend events, which typically represent evolving leaks. When these long-term leaks are fixed, not only is future leakage prevented, but there is often a reduction in the overall NRW. Figure 2. Hidden leakage at QUU.
Figure 3. Hidden leakage at Yarra Valley Water, detected in the stormwater drainage.
At Unitywater in 2014, the system identified the presence of potential leakage with both ‘trend events’ and ‘leak events’. Investigation by acoustic detection teams found a cluster of leaks totalling 2.1 L/s. Field estimation had provided sizes of 0.5 L/s for one of the leaks but, following repair, the reduction achieved was 1.3 L/s. This allowed for a more accurate measurement of the benefits and a saving of 66.15 ML. The background night flows of this zone were also then reduced back to target leakage levels for the zone (Figure 4). Another long-term leakage trend at Unitywater also resulted in a reduction of the background leakage of a zone by 4.2 L/s. This leakage trend analysed the period from the system start in July 2013 through to detection in October where it was resolved and repaired. Following repair, the night flows were reduced back to target levels, with an avoided annualised leakage saving of over 132 ML (Figure 5).
SMARTER ASSET MANAGEMENT AND AVOIDING FAILURES
AUGUST 2014 WATER
SMART SYSTEMS
Figure 4. A long-term background leakage cluster, detected and repaired.
An intelligent water network solution should not be limited to leakage and NRW. The system also tracks other signals such as pressure, enabling the utility to monitor the performance of its Pressure Reduction Valves (PRVs) and assets. The holistic approach taken by the system enables utilities to find unusual events like breaches or PRV failures and stop them from causing further bursts. These savings can be estimated from burst rate analysis before and after pressure management.
78
Technical Papers helped QUU avoid several consequential bursts, with their corresponding cost and customer interruptions (Figure 6). Similarly, at QUU a long-term breach was identified between two zones from the system’s events, including the specific “breach” event type. The breach was caused by railway construction work that resulted in a valve being left open beyond the duration of works. It was rectified and normal pressure management restored (Figure 7). This avoided loss of customer pressure, and customer interruptions from bursts. It was estimated to avoid up to 16 additional bursts per annum. Figure 5. Long-term background leakage “trend event” over a three-month period.
Figure 6. A cluster of bursts occurred in a city zone.
SMART SYSTEMS
Figure 7. A long-term breach was picked up. By having breaches or failed PRVs, the previous non-pressure managed states and high burst rates are returned to acceptable levels. Subsequently potential avoided burst rates, customer interruptions and costs can be estimated. In 2013 at QUU a series of major bursts (over 100 L/s) occurred over the course
WATER AUGUST 2014
of a week in a central city distribution zone. Using the system, this pattern was identified including several pressure alerts. Initially it was suspected there was a breach, but after further investigation a blocked PRV outlet port was found. If left unrepaired this loss of pressure management was estimated to cause up to 27 additional bursts per annum. This
ASSISTING IN CRITICAL EVENTS When a critical incident such as a major burst occurs it can have a substantial impact on a large number of customers, assets and infrastructure as seen recently in Ultimo in Sydney (Australian Broadcasting Company, 2013). The effective and quick resolution of these issues is incredibly important to avoid major damage to property, but also the reputation of the utility in the community (Ahern, 2011). The system has a variety of powerful event detection systems, but it can also be effective in assisting with critical response to major incidents using geo-location and event analysis. At Yarra Valley Water in 2014, the system raised an event for a large burst that had occurred in a zone with over 10,000 customers and fed by six PRV stations. This burst had not been reported by customers, but followed an unusually large number of pressure complaints that had been received. Within one hour, the system helped validate that there was indeed an issue in the zone and provided a geo-location of the likely location for the burst (Figure 8). Field Investigation teams inspected the area and, with some localised testing, identified the final location of the leak and resolved the issue. The system provided confirmation of the size and scale of the issue, a geo-location and repair confirmation to assist in a more efficient and secure response. QUU experienced a major critical event in an industrial DMA, where the system raised an event for flows continuing at high levels of 15 L/s. No bursts had been reported by customers. A field inspection was quickly performed and identified a large flow from an industrial customer
79
Technical Papers UNDERSTANDING NETWORK PERFORMANCE A major benefit of an intelligent water network system is its in-depth data analysis abilities. The system’s reporting functions have been used to understand the performance of a network and the behaviour of the system on a large scale. This can be done through a number of ways including high-level dashboards that summarise the performance of the water network from the bottom up or from detailed water balancing reports.
Figure 8. Major burst in a Yarra Valley Water zone.
Figure 9. A major leak on a customer fire service.
Yarra Valley Water has used the Water Balancing feature to assist with its detailed investigation of NRW performance in its distribution zones, super zones and billing regions to analyse the performance of their network from many levels and to identify NRW or data quality trouble spots. It has also used the system to assist with the calculation of NRW, including ways to generate accurate estimates for water carter use, volumes lost through bursts per month, and leakage. Similarly, the high-level summary dashboards are used by all three utilities to monitor performance in a quick ‘onestop shop’, where meter performance, zone performance, ILI and event processing time can be monitored in a quickly summarised fashion. The high level reporting, coupled with other reporting modules, has greatly improved the ability of the utilities to understand, visualise and analyse the vast ‘sea of data’ to make actionable changes in strategy.
CONCLUSIONS
Figure 10. The system’s reporting modules can be used to automatically perform bulk water analysis, water balancing and assist with detailed NRW analysis, as at Yarra Valley Water. location, of the same magnitude, some two weeks later (Figure 9). This was also quickly identified and resolved, resulting in an annualised avoided leakage loss of 473 ML, and the data enables utilities to recover costs from customers.
It is clear that smart water technologies are key to addressing both the drivers and challenges faced by utilities today, especially as more types of data are available, as these technologies play a significant role in
AUGUST 2014 WATER
SMART SYSTEMS
that was running in a nearby drainage creek. This customer was not aware of the problem. Investigations revealed that the leakage was coming from a fire service that is an unmetered and unbilled supply. It was repaired, but the system identified a subsequent leak at the
Intelligent Water Networks is an area of great innovation at water utilities, and there are still many remaining challenges. The TaKaDu solution has proven in the Australian environment to have assisted utilities achieve tangible savings and reductions in Non-Revenue Water. The large amount of incoming data can be filtered and grouped into identifiable and actionable events to save water, avoid leakage cost, prevent customer interruptions and assist in high-level reporting. Each of the utilities has had real benefits including avoided leakage costs, avoided interruptions and damages, as well as improvements in efficiency.
80
Technical Papers
Figure 11. The system has high-level reporting dashboards available to summarise the network performance up the hierarchy of zones and network segments including for ILI, data availability and zone performance. improving customer service, reducing leakage and energy costs, and increasing operational efficiency, thus allowing utilities to take a proactive approach to ageing infrastructure and other network challenges.
THE AUTHORS Justin Sorbello (email: Justin.sorbello@jacobs.com) is a Technical Engineering Lead for Intelligent Water Networks projects for Jacobs. Specifically, he is accountable for the water systems engineering and analysis, leakage reduction and optimisation strategy, data analysis and utilisation, business implementation and change management strategy for Jacobs TaKaDu projects.
SMART SYSTEMS
Revital Marck (email: revital.marck@takadu.com) is the Delivery Director at TaKaDu. Revital is responsible globally for the management and delivery of TaKaDu services and oversees the Delivery Group. She has been heavily involved in the deployments of TaKaDu systems in Australia. She holds a Bachelor of Computer Science from Hadassa College and an MBA from Ha’Universita Ha’Petuha.
REFERENCES Ahern E (2011): At Bursting Point. 5th Annual WIOA NSW Water Industry Engineers & Operators. Newcastle, Australia: Water Industry Operators Association of Australia. Australian Broadcasting Company (2013): Burst Water Main Floods Ultimo in Inner Sydney, Damages Roads. Retrieved May 6, 2014, from
WATER AUGUST 2014
ABC News: www.abc.net.au/news/2013-08-11/ burst-water-main-floods-ultimo/4878620 Australian Water Management Review (2013): i2O Water’s Advanced Pressure Management – The Six Benefits of Optimising Pressure in Water Distribution Networks. Retrieved April 5, 2014, from Industry News – Software And Modelling: www.awmr.com.au/water-news/ software-and-water-modelling/1309-i2owaters-advanced-pressure-management-thesix-benefits-of-optimising-pressure-in-waterdistribution-networks Balberg A & Hauber-Davidson G (2013): Smart Water Metering at Supermarkets for Proactive Leak Detection and Advanced Data Analysis. Water Journal, 40, 5, pp 85–88. Bendeli M & Hersh A (2013): Using a Real Options Approach to Value the Benefits of Condition Assessments Within a Risk Based Asset Management Framework. Water Journal, 40, 7, pp 63–67. Boyle T, Giurco D, Mukheibir P, Liu A, Moy C & White S (2013): Intelligent Metering for Urban Water: A Review. Water, 40, 5, pp 1052–1081, MDPI, Basil, Switzerland. de Graaf BR, Williamson F, Koerkamp M, Verhoef J, Wuestman R & Bajema B (2012). Implementation of an Innovative Sensor Technology for Effective Online Water Quality Monitoring in the Distribution Network. Water Practice and Technology, 7, 4, pp 99–100.
Retrieved May 6, 2014, from IBM Press Releases: www-03.ibm.com/press/au/en/ pressrelease/40800.wss Kane G, Zhang D, Lynch D & Bendeli M (2014): Sydney Water’s Critical Water Main Strategy and Implementation – A Quantitative, TripleBottom Line Approach to Risk Based Asset Management. Water Asset Management International, 10, 1, pp 19–24. Anda M, Le Gay Brereton F, Brennan J & Paskett E (2013): Smart Metering Infrastructure for Residential Water Efficiency: Results of a Trial in a Behavioural Change Program in Perth, Western Australia. First International Conference on Information and Communication Technologies for Sustainability (pp 116–122). Zurich: ICT4S–ICT For Sustainability. Sensus International (2013): Water 20/20: Bringing Smart Water Networks into Focus. Retrieved April 4, 2014, from Sensus International: sensus. com/documents/10157/1577608/Sensus_ Water2020-USweb.pdf/d67d0a75-255a-4a2086f1-d4548bfcdf78 Skinner R & Ewert J (2014): Addressing the 10 Key Integrated Water Management Challenges in an Australian Context. Water Journal, 40, 2, pp 58–60.
Derceto Aquadapt (2012): Winning Hearts and Minds at Unitywater. Retrieved May 6, 2014, from Derceto Case Study: www.derceto. com/Case-studies/Case-studies/pod-files/ CaseStudies/UnityWatercasestudy_USL_web_ April12.pdf
SWAN (Smart Water Networks Forum): (2014, January). SWAN Global Utility Survey. Retrieved May 5, 2014, from Smart Water Networks Forum Research: www.swan-forum.com/ research.html
du Plessis M & Killen C (2013): Valuing Water Industry R&D. Water Journal, 40, 6, pp 63–67.
United Nations (UN): 2013, March 22. SecretaryGeneral’s Message for 2013. Retrieved May 5, 2014, from World Water Day: www.un.org/en/ events/waterday/2013/sgmessage.shtml
Frost & Sullivan (2013): Analysis of the Global Smart Water Metering Market: Market Success Requires Finely-Tuned Regional Strategies. Mountain View, California: Analysis of the Global Smart Water Metering Market NCCE-15. IBM: (2013): Townsville Wins National Award with IBM Smarter Water Management Project.
Water Services Association of Australia (2012): Occasional Paper 27: Climate Change Adaptation and the Australian Urban Water Industry. Greensborough: Elements Strategic & Risk Management.
81
Technical Papers
SMART METERING ENABLES EFFECTIVE DEMAND MANAGEMENT DESIGN A case study to demonstrate that an early mixed-method baseline analysis is essential to designing robust, cost-effective demand management programs in remote communities K Ross, C Delaney, N Beard, K Fuller, S Mohr, C Mitchell
ABSTRACT The water demand and water use practices of each community are different. Designing cost-effective demand management programs requires investigating and responding directly to the unique water issues and opportunities of each community (Turner et al., 2010). As presented in this paper, a â&#x20AC;&#x2DC;mixedmethod baseline analysisâ&#x20AC;&#x2122; has proven to be valuable in developing a demand management program tailored to the distinctive community context. A mixed method baseline analysis is comprised of two interlinked components: (i) quantitative smart meter data analysis to create a detailed understanding of the water demand profile; and (ii) qualitative social research to understand the social, cultural and institutional influences that drive existing water patterns.
This paper shares the mixedmethod baseline analysis and resulting implications for a demand management program implemented in the remote Indigenous community of Gunbalanya, Northern Territory, in 2013. This paper is one of the first case studies to document how smart meters, as part of a mixed-method baseline analysis, can target demand programs in remote communities more cost-effectively, by enabling scarce program funds to be focused on areas of highest need and greatest impact. The smart meter component of the baseline analysis revealed leaks to be the greatest opportunity for demand reduction in the community, rather than the previous focus on consumption and household behaviours. The social research revealed a range of social
and cultural considerations around leaks in the community, which were important to respond to in the program design. The demand management program design was adjusted to enable a more accurate response to the specific water issues and opportunities uncovered by the mixed-method baseline analysis. The principles of the mixed method baseline analysis can be applied to any region to develop robust, costeffective, accurate and impactful demand management programs.
INTRODUCTION Water service delivery in remote communities Indigenous Essential Services (IES) Pty Ltd, a not-for-profit subsidiary of Power and Water Corporation, provides water services to 72 serviced remote
SMART SYSTEMS
Aerial view of Gunbalanya, with the Arnhem Land escarpment beyond (K Ross, April 2014).
AUGUST 2014 WATER
82
Technical Papers Indigenous communities and 66 smaller ‘homeland’ settlements peppered across the Territory. IES and its predecessors have provided electricity, water and sewerage services to Indigenous communities in the Northern Territory since 1987 (PWC, 2013). Water service delivery in the 72 remote communities involves unique challenges, including the small size of service locations, ageing infrastructure of variable standards and high-energy costs associated with the provision of water services (PWC, 2009). Remote communities also have a unique context for the design and delivery of demand management programs. Residential meters are not the norm, therefore demand management programs are often designed on bulk meter data analysis and lessons learned in other contexts. In the Northern Territory there is no water pricing for residents in public housing. Other important considerations are the need for and implications of crosscultural communication and mutual understanding as well as the relative economic disadvantage of the Indigenous community (PWC, 2009). Smart meters in remote communities
SMART SYSTEMS
Smart meters differ from normal, mechanical meters in that they can digitally display flow rates in real time, usually remotely. Smart meters and smart meter data have been increasingly used in Australia in water service delivery since 2008 (Giurco et al., 2008b). The demonstrated benefit in urban areas has been improved water management through distribution and customer leak detection, tailored demand management programs and policies, evidence-based customer education, and program evaluation (Giurco et al., 2008a; Giurco et al., 2010; Mead and Aravinthan, 2009). Recently, a novel mixed-method approach was used to reconcile differences between perceived and actual residential end-use water consumption in urban areas (Beal et al., 2011). To our knowledge this case study is the first documented program in Australia that has used a mixed method baseline analysis (smart meters in conjunction with social research) to design, monitor and evaluate a demand management program in a remote Indigenous community. This case study has many components to discuss, including the benefits of smart meters for program design, program
WATER AUGUST 2014
and water demand monitoring, program and action evaluation, stakeholder coordination and efficiency gains, and the overall cost effectiveness of smart meters in remote communities. The authors plan to present these aspects in various papers. This paper focuses on the benefits of a mixed-method baseline analysis in the design stage in order to develop robust demand management projects. Site of the demand management project: Gunbalanya Gunbalanya, an Indigenous community in western Arnhem Land, Northern Territory (NT), is experiencing increasing water scarcity and rising water demand. The town’s water is obtained from a shallow, sandy soil aquifer that depends on seasonal recharge. Its unique characteristics prohibit higher extraction rates, which means the community is at a high risk of water shortages at the end of most dry seasons. This water scarcity, coupled with increasing demand, triggered the development of a water demand management program led by Power and Water Corporation in 2013 that sought to involve the Gunbalanya community and key stakeholders to be water-wise (PWC, 2012). Gunbalanya (Oenpelli) is located approximately 300km east of Darwin, within the West Arnhem Regional Council (WARC) area. Situated in the dry tropics region, Gunbalanya is characterised by two hot tropical seasons: the dry (April–September) and the wet (October–March). The town is surrounded by floodplains that are inundated during wet seasons. As such, the main access road is usually impassable
during the wet season and the community is accessed via an airstrip. The most recent census estimates Gunbalanya’s population as 1,371 (ABS, 2011), but other estimates vary from 1,500 to 3,400 (NTG, 2014a; NTG, 2014b). Territory and national development initiatives suggest that further housing could be developed over the next five to 10 years (Australian Government, 2011; 2013), leading to increased population and water demand to an already stressed water source. Water provision and metering in Gunbalanya IES has been working since at least 2003 to address water scarcity concerns in Gunbalanya. The majority of the 268 serviced water connections in Gunbalanya are public housing. The NT Department of Housing owns and leases 163 public homes to Indigenous residents, while 94 are commercial and government buildings.
Gunbalanya is located in West Arnhem Shire, at the top of the Northern Territory (NT Dept of Local Government and Regions).
83
Technical Papers Technical/Appliances • Outdoor water-efficient appliances for households • Working with key maintenance agencies to respond to smart meter data analysis of high water use.
Gunbalanya has an estimated population around 1,500, with 268 serviced water connections (Google Maps). Only commercial and government premises are charged for water in remote communities under current NT policy, and as such have a quarterly water meter reading and billing cycle. All other lots were metered in 2003 to assist with measuring demand due to rising water scarcity issues. However, major challenges to reading all meters and maintaining them in reliable service in remote areas meant that the data was of only limited value in appropriately assessing the demand profile of the community. Previous bulk meter data analysis indicated that generally around 80% of water in the community is used in households, and only 20% of water is used in non-residential facilities (such as the school, clinic and the store) (PWC, 2012). System losses could not be easily estimated. Public housing consumption levels based on bulk data were coarsely estimated to be of the order of 1000 L/c/d (with poor confidence rating of the data) (PWC, 2007). Initial demand management program design for Gunbalanya
This draft community action plan proposed technical and social demand management components (PWC, 2012), including:
ISF was engaged by Power and Water to provide design recommendations, monitor smart meter data during implementation and evaluate the effectiveness of the program. To inform the design recommendations, ISF undertook a mixed-method baseline analysis within the community in April 2013, to explore and understand the demand patterns. This paper presents the findings from the mixed-method baseline analysis and describes how the findings influenced the program design. This case study demonstrates the value of a baseline analysis that provides a granular understanding of the water demand, and the reasons behind the water use patterns, for developing appropriate and well-targeted demand managed programs. The lessons from this baseline analysis provide transferrable lessons for designing demand management programs in this context.
APPROACH
• Household commitments to save water in the home
ISF used a mixed-method approach to undertake the baseline analysis, drawing on both quantitative and qualitative data sources. The quantitative method analysed smart meter data to provide a detailed breakdown of water demand patterns within the community, while the qualitative social research, including community surveys and stakeholder interviews, provided insights into water demand patterns.
• Daily community water use target and tracker.
First ISF analysed smart meter data to identify: (i) the different types of
Social/Behavioural • Water efficiency communication and marketing tools • Indigenous water conservation officers/educators
AUGUST 2014 WATER
SMART SYSTEMS
Based on the initial high-level bulk water analysis, which indicated high average consumption levels in public housing, the draft plan was to focus primarily on engagement with the public housing tenants and housing maintenance agencies and to use smart meter data to aim the program at the largest users.
In 2012, Power and Water received funding from the Federal Government to implement the demand management program. Power and Water installed smart meters between June and October 2012, and developed the “Community Action Plan: Water Efficiency in Gunbalanya Households” in a collaborative partnership with Gunbalanya community leaders and Project Partners (including NT Department of Housing, the West Arnhem Regional Council (WARC), and the NT Department of Community Services) in November 2012. Power and Water coordinated the partnership with these stakeholders to explore how smart meters would benefit the aims of all partners and how collaborative action on the smart meter analysis would improve the actions to decrease water demand.
The installation of smart meters was a key feature of the program. Power and Water recognised the limitations with using bulk meter data to, firstly, understand the community’s water use patterns and, secondly, to plan appropriate responses. Therefore, one of Power and Water’s goals for this innovative project was to use the analytical power of smart meter data to refine the program design, direct and monitor program action, and evaluate the program. Power and Water sought a mixed-method approach to both refine the program design and evaluate the program, recognising the value of integrating the technical and social aspects.
84
Technical Papers water demand; (ii) customer lots with excessive demand; and (iii) the largest opportunities for savings. Smart meter data from 257 properties was analysed. For this baseline analysis, water demand was divided into three categories: 1.
Legitimate consumption (i.e. actual customer usage; defined in the data by usage stopping and starting over periods < 24 hours);
2.
Intermittent leaks (i.e. behaviourally based leaks such as sprinklers left on, or hardware leaks such as toilet flushes that stick; defined in the data by consistent demand that lasts between 24 and 48 hours); and
3.
Continuous leaks (i.e. longer-term behaviourally-based or hardware leaks; defined in the data by demand lasting longer than 48 hours).
SMART SYSTEMS
To analyse the smart meter data, ISF developed custom scripts that separated water demand into these three categories across all lots. Initially, only three months of complete smart meter data was available for analysis. The analysis also calculated basic statistics including the mean, median rates of increase and the relative comparisons between water use types. For the purposes of this study, the suite of scripts analysed the smart meter data at two levels: the community as a whole (all 257 connections), as well as comparing public housing (163) and all other properties (94). Next, social research was conducted to gain insights into the influences that drive the identified water demand patterns. Results of the smart meter data analysis informed the interview and survey question design. Interviews were conducted with four groups: Indigenous community leaders (2), local West Arnhem Regional Council (WARC), school, business and health clinic employees (4) and Project Partners, including representatives of WARC, the NT Department of Housing, NT Department of Community Services and Power and Water (8). Topics included the interviewee’s role, goals, definition of success and perceptions of barriers in relation to the program. Brief surveys (12) and participatory mapping exercises with community members (25) focused on source, size, duration and impact of continuous leaks, with some investigation of outdoor water use and intermittent leaks.
WATER AUGUST 2014
RESULTS Leak volumes The mixed-method baseline analysis found leaks were a significant proportion of measured demand. The smart meter analysis suggested 20% of the measured consumer demand was lost in continuous leaks (Category 3 above). A further 14% was lost in intermittent leaks (Category 2). Stakeholder interviews reiterated perceptions around the ‘significant’ amount of leaks in public housing and their perceptions of the damage it causes to the assets, such as floor, wall, ceiling and electrical damage. Factors contributing to leaks The social research confirmed new homes had minimal leaks whereas every older home visited reported an existing or recent leak. The research identified potential drivers of the high leak volumes. Local employees felt that the main sources of continuous leaks in the community were corroding taps (which was corroborated by the housing maintenance and repairs database). A maintenance employee suggested the need for stainless steel tap upgrades instead of outdoor waterefficient appliances, which he considered to be unsuited for the water pressure, pH and social context. Stakeholders described the sources of intermittent leaks as extended periods of watering lawns, taps that were challenging to turn on and off (due to corroding materials) and observed consumer habits of leaving taps turned on. All groups perceived the length of time between the start of the leak and its rectification as a reason for high leak volumes, due to barriers in identifying, reporting and responding to leaks. Barriers to addressing leaks The social research highlighted several barriers and drivers for addressing leaks in public housing. The community surveys highlighted concerns over financial or other negative consequences as a barrier to reporting. Stakeholders corroborated a perception that public housing tenants may feel uncomfortable reporting leaks and fear negative consequences, such as financial charges. The surveys indicated that tenants were deterred from reporting leaks by the perceived length of time for the leak to be rectified. In addition, community members spoke of only certain
household members having cultural authority to report the leak; therefore leaks may go unreported for a variety of reasons (i.e. availability and mobility of those with authority). Community members described the main drivers for reporting leaks as concern for the health and safety of the children and frustration caused by the location of the leak, i.e. toilet leaking on the floor or large kitchen tap leaks. Both community surveys and stakeholder interviews confirmed that small leaks are tolerated and aren’t usually reported independently. Stakeholders perceived that water conservation is not a priority, nor well understood across the community, compared to broader community concerns. Legitimate consumption The mixed-method baseline analysis suggested low volumes of legitimate water consumption. The smart meter analysis indicated that half of public households consume relatively small volumes of water, less than 800L/d. Assuming an average of eight people per household, about half of the community members may consume less than 100 L per person per day. The local clinic reported high prevalence of skin disease, scabies and diarrhoea, which are associated with low water consumption. School staff also perceived low rates of washed clothes among children, and housing maintenance employees confirmed limited access to effective washing machines. Social marketing and education Interviews highlighted the perception that social marketing and community education materials need to be visual and show the relationship between aquifer levels and water outages. Community leaders felt visual communication was most effective in the community and suggested creating posters showing the aquifer levels during the wet and the dry season, and to relate the relationship of water levels to pressure (in this context lower aquifer levels means less water can be pumped and operators need to reduce the water available to the town, from the tank). Distribution leaks Community leaders and local employees perceived frequent instances of prolonged distribution leaks in the pipe network. The Power and Water representative in Gunbalanya reported difficulties in promptly addressing
85
Technical Papers distribution leaks because of the significant workload. These insights into leaks and consumption influenced the program design.
DISCUSSION OF PROGRAM DESIGN IMPLICATIONS Enhanced focus on leaks identification and reporting The quantitative volume and qualitative perceptions of leaks uncovered by the mixed-method baseline suggested that only a concerted effort to address the leaks throughout the entire water system would address the water scarcity concerns of this growing community. However, this demand program was focused on customers, therefore technical and social recommendations were developed to further tackle leak reduction on customer premises. On the technical side, it was recommended that the budget be increased to fix common forms of leaks (such as corroded taps) and water waste (such as missing sink plugs) by decreasing the budget for outdoor water-efficient appliances. It was also recommended that smart meter analysis of the “top 10 leaks” be shared with Project Partners regularly to address and fix the major leaks. On the social side, it was recommended that a collaborative community target of
‘all leaks reported’ replace the original community target of “x litres per person per day” (a specific target number had not yet been decided on in the draft action plan). Other social recommendations were to further refine messages delivered by the Indigenous water conservation officers to specifically address and build capacity of public housing tenants to help overcome barriers to leak reporting; for example, messaging that: explains the benefit of reporting leaks (e.g. improved pressure, decreased health risk); reassures community members they will not get into trouble or be charged as a result of reporting a leak; helps families recognise all types of leaks from small to large and plan who will report leaks. Social marketing implications Keeping community social marketing simple and clear while avoiding messages that relate to water consumption behaviours and health was a recommendation that emerged from the baseline analysis. The smart meter analysis of household water consumption directed the program away from educating on water-use behaviours. The World Health Organisation defines ‘sufficient water’ use as between 50 and 100 L/p/d to ensure that most basic needs are met and few health
concerns arise (WHO, 2003). The smart meter data suggests that about half of Gunbalanya residents are near the WHO guideline. This is not to say that the water isn’t available, but rather that half the community members are using ‘sufficient’ volumes of water or less. The qualitative research suggested that the education or messages should not inadvertently encourage community members to prioritise water efficiency actions at the expense of health outcomes. Therefore, it was recommended that all messages relating to shorter showering times, washing clothes or bedding with a full load (in alignment with guidance in the National Indigenous Housing Guideline, Australian Government, 2007), flushing toilets with a half or full flush as needed, and children playing under outdoor water taps are not included in the program. A smaller number of targeted messages were recommended, including: (i) turn off taps and help others turn off taps; (ii) report leaks to Shire; (iii) use a sink plug; and (iv) explain that aquifer levels vary between the wet and dry season (to explain the reasons why these actions are important).
SMART SYSTEMS
Gunbalanya at the end of the wet season (K Ross, April 2014).
AUGUST 2014 WATER
86
Technical Papers Influence of baseline timing on program design Timing constraints external to managers’ control influenced the ability to refine several aspects of the program design. The program had to be pre-designed to get external funding and smart meters were included, but practicalities of delivering the whole project in 18 months meant aspects had to be delivered in tandem. The project decision-making and rollout had to start before a detailed smart meter analysis could be undertaken. For example, Project Partners agreed on the distribution of outdoor water-efficient appliances to community housing (to test the resulting reduction in demand) before the smart meter analysis. While the smart meter and social analysis indicated that consumption was not the primary water use area that needed attention, and that investments should focus on rectifying leaks, the prior agreement meant that outdoor appliances remained as an investment for the program. Additional insights were discovered as smart meter analysis grew more sophisticated during the project implementation. This subsequent analysis would have improved program design if timing had allowed smart meter analysis to be more thorough, earlier. For example, the subsequent research indicated that:
SMART SYSTEMS
• Continuous and intermittent leaks in public housing were losing similar volumes for non-public housing properties, meaning per property losses are higher in other properties than in public housing. Non-residential leaks were addressed through ad hoc interventions by Power and Water to the highest users, which were also directed by the smart meter data analysis. Audits were performed as part of a related project to assess large customer consumption issues; however the smart meter analysis indicates this is an area for future expansion of the program. • The smart meter analysis confirmed a correlation between the age of the housing stock and existence of maintenance leaks, which means demand management program components could be developed specifically to support the oldest housing stock. • Distribution leak volumes were potentially equal to or greater than building leak volumes, which indicates
WATER AUGUST 2014
opportunities to prioritise investigation of distribution leaks (available bulk data had significant error, so needs further investigation). It is desirable to have two years of smart meter data to thoroughly analyse at the beginning of program design in order to feed into program development. However, the design recommendations coming out of three months of data still proved very useful in enabling a more robust program design for Gunbalanya. Transferability to other communities The mixed-method baseline approach is transferable to all community types and means that demand management funds can be targeted, cost-effective and successful. This method can be summarised in several important principles. Firstly, design the demand management program based on a tailored and triangulated evidence base, drawing on the combined power of smart meter analysis and social research. It is also important to cross-reference multiple data sources to ensure that the opportunities for greatest cost-effective savings are discovered and addressed appropriately. For example, check and cross-reference the stories arising from the smart meter data analysis, community interviews, repair and maintenance employees and database, community leaders, etc. Secondly, where possible (considering budget and other time constraints), allow for enough time to conduct a thorough and meaningful investigation before allocating funds to specific components of the demand management project. This ensures scope to allocate resources accordingly from the beginning, to the areas of greatest need identified in the baseline analysis. Finally, the baseline analysis should be holistic and include a water balance of the entire system (Turner et al., 2010). That is, when designing a water-reduction program in rural or remote communities, investigate all potential sources of water waste, including: supply infrastructure leaks, dwelling leaks and behavioural leaks.
management programs need to respond to their unique social, cultural and infrastructure issues. This paper demonstrates that an early and thorough mixed-method baseline analysis (including both smart meter analysis and social research) is essential to designing robust, communityappropriate and cost-effective demand management programs in remote communities. This baseline analysis can help reduce demand by enabling scarce program funds to be focused on areas of highest need and greatest impact. The complementary use of smart meter data analysis with social research provided new insights into the greatest opportunities for demand reduction and led to a more robust program design in Gunbalanya. The draft action plan was aimed at behaviour change and sought to trial and evaluate community engagement tools and appliance retrofits. These engagement tools were developed as a response to bulk meter data analysis, which showed 1000L per person per day. The results of the baseline analysis offered a clear identification of the problem and the program was altered to be more robust and cost-effective. The mixed-method baseline suggested a concerted effort to address leaks throughout the system. Addressing maintenance and intermittent leaks became the primary goal of the program, shifting from an initial emphasis on household consumption. Modified program components that responded to the baseline analysis included the rollout of stainless steel taps, social marketing that centered on reporting leaks, and a community commitment to report all leaks (instead of water use targets).
CONCLUSION
This mixed-method baseline approach is transferable to all community types and means that demand management funds can be targeted, cost-effective and successful. This case study presents a framework for designing effective demand management programs using the insights afforded by smart meters and social research.
The many variables that influence water demand are often complex and multilayered. Hence, it is imperative to analyse the water context qualitatively and quantitatively to highlight the primary water issues and opportunities for demand management. To be successful and cost-effective, community demand
Employing a mixed-method baseline analysis, with both smart meter data analysis and social research, to inform program design prior to program implementation, provides greater potential for water savings by responding to and targeting the community-specific context. Engaging in a mixed-method
87
Technical Papers baseline analysis will identify the water use type and user group that requires the most attention, resulting in greater demand reduction and a greater return on investment than a generic program. Future articles on this case study will demonstrate how smart meters can also provide an ongoing method of monitoring water usage changes and an active means of conducting ongoing demand management by advising customers, as well as supporting program evaluation.
THE AUTHORS Katie Ross (email: Katie.Ross@uts.edu. au) works as a Project Director and Manager on projects promoting social and technical system transformation. Katie’s current research seeks to strengthen the long-term performance of decentralised systems and improve equity consideration in technical processes such as water efficiency and safety, in order to improve the long-term impact of these types of programs. She is also expert in innovative community engagement, capacity building and workshop design. Candice Delaney (email: Candice.Moy@uts.edu. au) is a Social Researcher specialising in mixed methods research design and analysis. Candice’s research explores the intersection of technologies and sustainable practices, focusing on the sociocultural drivers and barriers. Her research has drawn heavily on social theories while maintaining practical industry relevance.
Kathryn Fuller (email: Kathryn.Fuller@power water.com.au) is a Senior Community Engagement Officer for water and energy demand management in
Dr Steve Mohr (email: Steve.Mohr@uts.edu.au) is a Senior Research Consultant, specialising in data analysis, forecasting resource depletion, numerical modelling and the evaluation of energy and water savings pilot programs. Steve has a PhD in Chemical Engineering from the University of Newcastle, Australia. Professor Cynthia Mitchell has a national and international reputation for her transdisciplinary work for economic, environmental and social sustainability in the water and wastewater sector, with a particular focus on the planning, governance and management of distributed infrastructure and water and nutrient recycling systems. Professor Mitchell’s expertise covers strategic, tactical and operational domains, and encompasses both quantitative and qualitative data and analysis across economic, social and environmental performance and evaluation, and the synthesis of these analyses into strategy-level decisions.
REFERENCES Australian Bureau of Statistics (2011): 2011 Census. Accessed 10 June 2014: www.censusdata.abs.gov.au Australian Government (2007): National Indigenous Housing Guide: Improving the Living Environment for Safety, Health and Sustainability. Department of Families, Community Services and Indigenous Affairs.
(2008–2013). Accessed 6 June 2014: www.dss.gov.au Beal C, Stewart R & Fielding K (2011): A Novel Mixed Method Smart Metering Approach to Reconciling Differences Between Perceived and Actual Residential End Use Water Consumption. Journal of Cleaner Production: doi:10.1016/j.jclepro.2011.09.007. Giurco D, Carrard N, McFallan S, Nalbantoglu M, Inman M, Thornton N & White S (2008a): Residential End-Use Measurement Guidebook: A Guide to Study Design, Sampling and Technology. Prepared by the Institute for Sustainable Futures, UTS and CSIRO for the Smart Water Fund, Victoria. Guirco D, Carrard N, Wang X, Inman M & Nguyen M (2008b): Innovative Smart Metering Technology and Its Role in End-Use Measurement. Paper presented at Water Efficiency 2008, Gold Coast, 31 March–2 April 2008. Institute for Sustainable Futures, University of Technology Sydney and CSIRO Sustainable Ecosystems. Giurco D, White S & Stewart R (2010): Smart Metering and Water End-Use Data: Conservation Benefits and Privacy Risks. Water, 2, 3, pp 461–467. Mead N & Aravinthan V (2009): Investigation of Household Water Consumption Using Smart Metering System. Desalination and Water Treatment, Volume 11, Issue 1–3, pp 115–123. NT Government (2014a): Northern Territory Government, accessed 15 January 2014: www.teaching.nt.gov.au/remote/index. cfm?attributes.fuseaction=GUNBALANYA NT Government (2014b): Northern Territory Policy, accessed 15 January 2014: www.pfes. nt.gov.au/Police/Contact-police/RemoteStation-Profiles/Gunbalanya.aspx Power and Water Corporation (2009): Sustainable Water Management Report 2008– 09: Indigenous Communities of the Northern Territory. Power and Water Corporation. Power and Water Corporation (2012): “Community Action Plan: Water and Energy Efficiency in Gunbalanya Households.” Draft document prepared by Power and Water in partnership with Gunbalanya community representatives. Power and Water Corporation (2013): Indigenous Essential Services Pty Ltd Annual Report: 2013. Accessed 6 June 2014: www. powerwater.com.au
Australian Government (2011): Remote Service Delivery National Partnership Agreement: 2010–11 Annual Report to COAG. Jurisdictional Report Cards. Accessed 6 June 2014: www.coag.gov.au
Turner A, Willetts J, Fane S, Giurco D, Chong J, Kazaglis A & White S (2010): Guide to Demand Management and Integrated Resource Planning for Urban Water. Prepared by the Institute for Sustainable Futures, University of Technology Sydney for the National Water Commission and the Water Services Association of Australia, Inc.
Australian Government (2013): National Partnership Agreement on Remote Indigenous Housing (NPARIH): Review of Progress
WHO (2003): Domestic Water Quantity, Service, Level and Health. World Health Organisation, Geneva.
AUGUST 2014 WATER
SMART SYSTEMS
Nerida Beard (email: Nerida. Beard@powerwater.com.au) is an Environmental Engineer with a Masters in Applied Anthropology in Participatory Development, and Manager of Water and Energy Demand Management for Power and Water Corporation’s Remote Operations Unit. For the past six years Nerida has led the community water planning and water and energy demand management initiatives for NT large and small remote Indigenous communities responsible to Power and Water.
remote communities for Power and Water Corporation and is President of the NT AWA Committee. She has spent five years working on water quality and treatment and the last three years on remote community engagement. In 2011 she spent five months in Nepal working on Water Safety Plans through Engineers Without Borders with Nepal Water for Health. In 2011 and 2012 she worked with several outstation and homeland water service providers to improve water management using the Community Water Planner Field Guide and other resources.
88
water Business
water business SAFE WORK AUSTRALIA AWARD FOR ZETCO Zetco Valves has been awarded the 2014 Award for the Best Workplace Health and Safety Practices in a Small Business by Safe Work Australia. Following on from its success in the NSW awards, Zetco was nominated by WorkCover NSW for the National Awards. Commenting on Zetco, the judges stated, “Demonstrating that business of all sizes can make a difference, Zetco took out the small business category for taking the initiative to put in place technology solutions that larger organisations have failed to, achieving both safety and commercial benefits as a result.” Zetco is delighted to have its commitment to WHS recognised nationally. Since 2007, there has been a considerable focus on improving the health and safety of the working environment. This has not only delivered considerable gains in terms of reduced risk, but there has also been substantial progress made in terms of worker comfort, which has ultimately led to increased productivity. For more information go to zetco.com.au
disinfectants to destroy germs and bacteria in water that can make us sick. They can be effective against almost all bacteria and viruses as well as algae, fungi, some minerals and man-made chemical pollutants. One of the main uses of chlorine that we are all familiar with is in swimming pools and spas, where the chlorine kills harmful microorganisms that can cause health-related problems. Chlorine-based swimming pool and spa disinfectants help prevent a host of health problems including swimmers’ ear, athlete’s foot, skin rashes and diarrhoea. An important thing to remember is the chlorine chemical must be stored and treated properly to ensure it is effective in use. A dosing chlorinating unit is used to dose chemicals into water. These chemicals can include chlorine for freshwater systems, corrosion inhibitors for main engine cooling water and pH adjustments of freshwater.
adjust fresh water, pre-chlorinate evaporated water or bunker water on its way to the freshwater holding tank, or re-chlorinate water before it is distributed. The pre-chlorination systems are normally controlled by flow meters in bunker water flow line and evaporated water flow line respectively. This ensures the right amount of chlorine is dosed into the actual water flow in the water line. Polymaster’s innovative new dosing tanks are a safer and more effective solution for storing and dosing chlorine as the Polyethylene material will not corrode – as opposed to other storing methods that will wear away over time. Furthermore, Polymaster tanks prevent gassing off on pump suction lines by inserting suction lines at the base of the tank.
The most common applications of a dosing unit are to pre-chlorinate or pH-
A chlorine-dosing pump adds a carefully measured amount of diluted chlorine to the system as the water passes into a tank. The amount of chlorine in the water needs to be monitored continuously to ensure the level
Polymaster dosing tanks.
ChemMaster® bunded tank.
THE PURE FACTS ABOUT CHLORINE Chlorine is one of the most abundant naturally occurring building blocks and is used in lots of products we use daily, including water purification systems. Unfortunately there is a commonly held misbelief that people would be better off without chemicals like chlorine. The fact is, most water systems use chlorine-based
water august 2014
89
water Business stays within the recommended limits. Too little and not all the contaminants will be destroyed; too much and it can be harmful to our health. The ideal set-up for dosing chlorine in an easy-to-use system is for a dosing pump to be mounted to a small Polymaster dosing tank. For a larger system, larger tanks are available from the Polymaster range. To prevent against the possibility of a tank inside an aged concrete bund leaking chemicals outside the tank and causing a serious OH&S/WHS issue, a Polymaster ChemMaster® bunded tank can be installed. ChemMaster® bunded tanks range from 1,500 litres to 10,000 litres to suit any application and are compliant to all specifications with lower costs and faster installations For remote or temporary dosing of chlorine, a ChemMaster® bunded tank offers the ideal solution with all pumps and instrumentation mounted into the cabinet, and the tank can simply be put in place and then removed when no longer needed without the need for any civil or constructional works. ChemMaster® tanks are not subject to rainwater ingress and have a lockable
cabinet door to keep out unauthorised personnel. For added reassurance, they are constructed from PE material that is totally UV-resistant and will not break down over time in the sun. For more information please go to polymaster.com.au
STUDENTS CHALLENGE CURRENT PATTERNS OF WATER, ENERGY AND NUTRIENT USE IN CITIES As more than half the global population now call the urban environment home, ensuring the sustainability of water-dependent services, including water supply and food and energy generation to urban areas, is crucial. We need to reduce the linear flow of water, material resources and energy, through promoting technologies and practices that achieve recovery, re-use and demand reduction. In pursuing this goal, 10 International WaterCentre (IWC) Master of Integrated Water Management participants, from a range of water utilities and elsewhere across Australia including Water Corp, Wannon Water, Melbourne Water, Unity Water and
The tested & proven mechanical seal that requires no maintenance, tolerates movement & exhibits longlife. RESISTANT TO: * AIR *CHEMICALS *FUELS *WATER *GAS
Bolt Pressure plate Pipe of any size (up to 2.4m dia.)
This session was the face-to-face intensive part of the module Urban Metabolism: Resource and Energy Recovery Systems, which is delivered using a blended approach of face-to-face and online teaching. The participants learned about the direct and embedded (or virtual) flows of water, food and energy in our cities. They evaluated the sustainability of those flows and ways that our cities might become more resilient to external resource or economic changes by recovering and recycling water, nutrients and energy. They learned how different elements of our urban water systems use energy, and where the biggest ‘bang for the buck’ opportunities lie for reducing water-related energy and recovering energy from water systems. Mass balance modelling was offered as a key technique for characterising and assessing the feasibility of recovery and recycling approaches at different scales and the functioning of different water recycling
HYDROVAR, the modern variable speed pump drive is taking pumping to a new level of flexibility and efficiency. Call us to discuss your applications: Melbourne 03 9793 9999 Sydney 02 9671 3666 Brisbane 07 3200 6488
2 hour Fire Rating
www.projex.com.au (02) 8336 1666
Seqwater, recently spent two-and-a-half days learning how to make the water, food and energy systems that service our cities more sustainable and resilient.
mail@projex.com.au
Email: info@brownbros.com.au Web: www.brownbros.com.au DELIVERING PUMPING SOLUTIONS
august 2014 water
90
water Business The module is delivered by Dr Steven Pratt, IWC Senior Lecturer in Integrated Water Cycle Engineering at The University of Queensland (UQ) School of Chemical Engineering, Dr Steven Kenway, WaterEnergy-Carbon Research Group Leader at UQ Advanced Water Management Centre, and Dr Brian S McIntosh, Senior Lecturer in Integrated Water Management at IWC. and nutrient (N, P and organic matter) recovery approaches and technologies. Participants visited City Food Growers’ urban farm and urban farming training centre in Samford, Brisbane, and discussed how stormwater, rainwater and recycled wastewater might play a role in supplying the farm as it grows. They also visited Wynnum WWTP to see how water recycling technology can play an important role in taking heavy industrial water users off the grid by supplying them with water recycled from municipal wastewater. At the plant, participants learned about the process technologies involved, including the MFRO plant, and discussed the opportunities at different scales for using water recycling in engineering and commercial terms, and how to costeffectively recover and reuse biosolids and recovered P in the form of struvite. IWC’s Master of Integrated Water Management offers the Urban Metabolism: Resource and Energy Recovery Systems module as part of its Urban Water specialisation stream. Viewing urban areas as systems that ‘metabolise’ resource inputs, ultimately releasing them back to the environment as wastes, this module challenges current patterns of water, energy and nutrient use in cities as inefficient and unsustainable. Emphasis is placed on water, with coverage of technologies and management approaches to manipulate water flow in urban systems to improve ‘metabolism’ by reducing raw water intake and recovering and using the resources that wastewater carries, particularly energy, nitrogen and phosphorous. The module equips participants to critically assess the resource efficiency and sustainability of urban systems from household through development to whole city scales, to systematically quantify physical flows in complex urban systems, and to construct and use urban metabolism models to characterise and evaluate options for improving urban sustainability.
water august 2014
For more information about the Master of Integrated Water Management please visit IWC’s website: www.watercentre. org/education/programs. Full-tuition scholarships are currently available with applications closing on 1 October for domestic students.
TURNING MINING WASTEWATER INTO RAINWATER A new cost-effective technology to treat mining wastewater and reduce sludge by up to 90 per cent has been used for the first time at a commercial mine. The technology, called Virtual Curtain, was used to remove metal contaminants from wastewater at a Queensland mine and the equivalent of around 20 Olympic swimming pools of rainwater-quality water was safely discharged. Sludge is a semi-solid by-product of wastewater treatment and reducing the amount produced has huge environmental and economic benefits. “Our treatment produced only a fraction of the sludge that a conventional limebased method would have and allowed the mine water to be treated in a more environmentally sound way,” CSIRO scientist Dr Grant Douglas said. “Reducing the amount of sludge is beneficial because the costly and timely steps involved to move and dispose it can be reduced.”
Given the Australian mining industry is estimated to generate hundreds of millions of tonnes of wastewater each year, the technology opens a significant opportunity for companies to improve water management practices and be more sustainable. “The technology can produce a material high in metal value, which can be reprocessed to increase a miner’s overall recovery rate and partially offset treatment costs,” Dr Douglas said. Virtual Curtain utilises hydrotalcites, which are minerals sometimes found in stomach antacids, to simultaneously trap a variety of contaminants, including arsenic, cadmium, and iron, in one step. Dr Douglas and his team developed the technology after discovering that hydrotalcites could be formed by adjusting the concentrations of common wastewater contaminants, aluminium and magnesium, to an ideal ratio and then by increasing the pH. “By using contaminants already present in the wastewater we have avoided the need for expensive infrastructure and complicated chemistry to treat the waste,” he said. “If required, the treated water can be purified much more efficiently via reverse osmosis and either released to the environment or recycled back into the plant, so it has huge benefits for mining operators in arid regions such as Australia and Chile. “It is a more efficient and economic way to treat wastewater and is enabling the global mining industry to reduce its environmental footprint and extract wealth from waste.” The licensed technology, which can be applied to a range of industrial applications, is available through Australian company Virtual Curtain Limited.
91
water Business NOV MONO SCORES PRESSURE SEWER SYSTEM SUCCESS IN AUSTRALIA NOV Mono has secured a significant success by being nominated as the preferred supplier for a major new pressure sewer network in Australia. Having evaluated various other alternatives, urban water corporation Wannon Water has chosen Mono’s innovative InviziQ™ pressure sewer system as the most cost-effective and easymaintenance option for the Dutton Way project in Portland, Victoria. The Dutton Way residential project currently houses 180 properties that are serviced by septic sewage tanks. This figure will increase to 314 homes, all of which will have the option to install an InviziQ™ sewage pumping system that feeds into the existing Portland sewer network. The InviziQ™ system is the perfect answer for a development like Dutton Way, as it will give each home access to a highly effective sewage solution and can be scaled up as new properties are added over time. “We were able to present the InviziQ™ system to Wannon Water, and took the opportunity to demonstrate our ability to provide technical support for a largescale project such as this,” adds Mono’s Technical Sales Representative, Daniel McClusky. “As the InviziQ™ system used on the Dutton Way project is installed by a certified installer, free training sessions have been provided for local contractors to obtain certified status.” Any Dutton Way resident who chooses to install an InviziQ™ system on their property will be supported by Wannon Water, who will be responsible for maintaining the unit’s pump and motor assemblies for life. Designed as an intelligent alternative to conventional gravity sewering options, InviziQ™ provides controlled transfer of sewage, but because it does not rely on gravity it offers the freedom to install sewers in any area, irrespective of the terrain, slope, environmental sensitivity or topography. It
features a network constructed from small diameter pipe, and can be installed either in narrow trenches or via directional drilling. This gives virtually unlimited freedom in the design and layout of the network, which can then be sized to meet the specific needs of each individual project. InviziQ™ uses advanced PCB-based control technology and versatile software, allowing it to self-monitor and run diagnostic tests to ensure that the system is operating efficiently. It can also support two-way telemetry for remote monitoring, and multiple InviziQ™ systems can be linked to enable centralised network management. For more details please visit www. monopumps.com.au or call 1800 333 138.
FLOLEVEL TECHNOLOGIES LAUNCHES NEW ACOUSTIC DENSITY INTERFACE TRANSMITTER FloLevel Technologies, an innovator of level measurement products, has launched a new self-cleaning acoustic density interface transmitter for mining and applications that suffer from build-up issues. The new technology accurately measures most liquid/slurry solutions where an interface of up to two densities exists, that need to be monitored continuously. The level interface transmitter tracks liquid to liquid interface, liquid to paste interface, and liquid to granular interface. It is a highpowered ultrasonic self-cleaning transmitter that is not affected by changes in the conductivity and dielectric of the solution. The pulse amplitude is great enough to cause a phenomenon called “rarefaction”, which causes cavitation to be produced from the array transducer diaphragms as they pulse.
The cavitation bubbles oscillate in front of the diaphragm, which cause implosions that generate high energy levels, removing scale and other build-up problems. “With over 30 years of experience from many different applications in the mining industry, we have developed a Density Interface transmitter that will significantly improve automation control in very difficult interface applications and significantly cut costs for the mining industry,” says Robert Stirling, owner and inventor of FloLevel Technologies. The FloLevel system is easy to install from the top of the tank and easy to calibrate. It comes with adjustable 316SS bracket, flange mounting options and a colour display controller mounted in a stainless steel enclosure. They can measure the density interface, with a maximum control range of 6400mm and resolution accuracy options available are 15mm and 25mm. Various output capability options are available, like 3 x 4-20Ma, Modbus, ProfiBus, Foundation FieldBus, DeviceNet, and Ethernet. The FloLevel Array is suitable for all mineral slurry applications. For more information please contact robert.stirling@flo-level.com.au
MINISTER FOR TOURISM INSPECTS AWARD-WINNING WATER DISINFECTION TECHNOLOGY Minister for Tourism, Major Events, Small Business and the Commonwealth Games, Jann Stuckey recently took part in an ‘access all areas’ tour of Brisbane water disinfection technology manufacturer, Australian Innovative Systems (AIS). AIS designs, produces and manufactures chlorine generators for commercial and residential use. Ms Stuckey inspected examples of the innovative water disinfection systems that will be keeping the water clean and safe at the Gold Coast Aquatic Centre (GCAC) – one of the aquatic venues for the 2014 Pan Pacific Swimming Championships and the Gold Coast 2018 Commonwealth Games. AIS Chief Executive Officer, Elena Gosse, showed Ms Stuckey the company’s award winning AutoChlor™ and EcoLine™ chlorination systems which will operate in three of the swimming pools at the GCAC. The GCAC is currently under refurbishment until September 2014 and is one of seven recreational and competition aquatic centres operated by the City of Gold Coast’s Council. Ms Stuckey said she was pleased that a local company such as AIS was producing technology of such a world-class standard.
august 2014 water
92
Water Business The company, which has been in business for over 20 years, is 100% Queensland-owned and operated and employs over 60 staff. “This is a perfect example of innovative, locally designed and manufactured technology holding its own on the world stage,” Ms Stuckey said. “AIS has exported its water disinfection technology to over 55 countries worldwide. It is wonderful that the Gold Coast Aquatic Centre has been able to source what it requires less than an hour’s drive away.” Ms Gosse said that the company was honoured to have its technology specified for the GAC project by highly respected aquatic engineer, Paul Stevenson of Stevenson + Associates. For the pools that the AIS technology will be operating in, the GAC can bid farewell to transporting, storing and dosing chlorine. “One of the major benefits of our water disinfection systems is that chlorine is produced automatically, onsite and inline via a process known as electrolysis. This means that commercial facilities can stop the endless and hazardous cycle of chlorine transportation, storage and dosing. “Our systems are in use in many municipal pools, hotel and resort pools and water parks in Australia and overseas,” Elena said.
The new Tsurumi model, called the LH4110-W, will change the way mining engineers quarry and construction operators carry out dewatering duties. “Being able to use one pump to get up to a 200-metre total head is a huge breakthrough,” said Aussie Pumps’ Craig Bridgement. “To think that Tsurumi has been able to achieve this with a pump that provides a 1,000 litre per minute maximum flow, but is only 23 inches (592mm) in diameter is a revolution,” he said. Tsurumi’s LH-W series are a super high-head version of the existing LH range. They feature two abrasion-resistant, high chrome closed impellers and a centre-mounted discharge flange that ensures the pump is balanced for lifting. The LH-W range are available with discharge ports of between 50–100mm (2 to 4 inches) and are a slim-line design enabling the pump to be used in bores and wells, with major cost reductions for users. The big benefit for operators is the pump’s ability to be able to move water from substantial depths without needing to stage dewatering through ponds or tanks. That creates a huge opportunity for cost reduction for contractors.
WATER AUGUST 2014
The pump comes with a 2-pole, 415-volt motor, driving the impeller through a hightensile, stainless steel shaft supported by deep groove ball bearings.
For further information including a free selection guide to submersible pump applications and engineering data is available from Australian Pump Industries, www.aussiepumps.com.au
“What most people don’t realise is that swimmers are actually smelling chloramines rather than chlorine and strong chloramine levels could be a sign that the level of disinfection may be compromised.
A new Tsurumi heavy-duty dewatering pump that delivers heads of up to 200 metres has been introduced by Australian Pump Industries. Aussie Pumps are the sole Australian distributor for Tsurumi, the world’s biggest manufacturer of submersible pumps.
The anti-wicking cable block on the cable entry is another major Tsurumi breakthrough in dewatering pump design. The block prevents water incursion due to capillary wicking should the power cable be damaged or the end submerged. Tsurumi claims this eliminates around 40–50% of submersible pump failures, again delivering lower operating costs and significantly improving reliability.
The company is working on a 316 stainless steel version of the big LH-W high end pump for the mines where there is specific corrosive liquid issues. A 1000-volt version may also be available in coming months.
“This reaction causes volatile chloramines to become airborne and create that terrible ‘chlorine smell’ that can sometimes affect the eyes, skin and breathing.
HIGH HEAD TSURUMI SUBMERSIBLE
A unique oil lifter guide vane inside the oil chamber ensures the mechanical seal is lubricated even if the oil level falls. This increases the time between routine pump maintenance and dramatically extends operating life.
Tsurumi Pump, based in Osaka, Japan, currently operates plants with a capability of producing up to 1.4 million pumps per annum. They are considered the most advanced submersible pump manufacturer in the world with a focus on dewatering, construction, sewage and wastewater.
“As well as the obvious occupational health and safety benefits, our systems help to reduce chloramines which are formed when ‘active chlorine’ in the pool water reacts with contamination in the pool such as urine, sweat or other body secretions.
“AIS technology takes the guesswork out of the equation and makes maintaining a clean and safe pool environment easy.”
The LH4110-W incorporates all of Tsurumi’s standard features that build reliability. Those features include a fully lubricated dual silicon carbide mechanical seal enclosed in an oil chamber. This eliminates spring failure caused by corrosion or abrasion and keeps both surfaces of the mechanical seal lubricated and cool.
Advertisers Index Brown Brothers Engineering
91
International WaterCentre
17 74
Comdain
3
James Cummings
Enware
7
Nov Mono
eWater
5
Pentair
Franklin Electric
OBC
9 IFC
Polymaster
19
Georg Fischer
31
Projex
91
Hach Pacific
29
Water Infrastructure Group
15
Hanna Instruments
24
Zetco
IBC
Moving Water is our Business
Commercial.
Golf courses.
Golf courses.
Industrial. VR vertical multistage pump with DrivE-Tech VFD
Now more than ever above or below ground, you can find Franklin products in places you never thought to look. Our centrifugal, VR â&#x20AC;&#x201C; Series stainless steel pumps with DrivE-Tech provide reliable, long-term operation that perform over a wide variety of applications for water system pumping, processing, building services and pressure boosting applications. 1300 FranKLin (1300 372655) franklinwater.com/au
FE1013 02/14