Environmental Science & Engineering Magazine | June 2023

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Responding to the Iqaluit water crisis

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TECHNICAL ADVISORY BOARD

Archis Ambulkar, OCT Water Quality Academy

Gary Burrows, City of London

Patrick Coleman, Stantec

Bill De Angelis, Metrolinx

Mohammed Elenany, Urban Systems

William Fernandes, City of Toronto

Marie Meunier, John Meunier Inc., Québec

Tony Petrucci, Black & Veatch

Environmental Science & Engineering is a bi‑monthly business publication of Environmental Science & Engineering Publications Inc. An all Canadian publication, ES&E provides authoritative editorial coverage of Canada’s municipal and industrial environmental control systems and drinking water treatment and distribution.

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Information contained in ES&E has been compiled from sources believed to be correct. ES&E cannot be responsible for the accuracy of articles or other editorial matter. Articles in this magazine are intended to provide information rather than give legal or other professional advice.

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ES&E Magazine celebrates 35 years of publishing

The year 2023 is indeed a milestone year. It marks Environmental Science & Engineering Magazine’s 35th birthday and 130 years of environmental journalism in Canada. It also marks the 40th anniversary of a research project I did to commemorate Water & Pollution Control Magazine’s (W&PC) 90th birthday in 1983.

W&PC’s origins began 130 years ago, when it was launched as The Canadian Engineer. W&PC had been a respected publication which had several name changes over its lifespan after it began as a general magazine serving professional engineers. But, even in its early days, the publication W&PC had a profound interest in environmental engineering. Some of the early environmental engineering giants were featured in W&PC and it would be salutary to many environmental groups to know that vigorous environmental concerns and remediation had taken place as early as the 1800s.

Many things are conceived at parties and, appropriately, it was at a publishing event that my father Tom Davey and I attended in 1987 that the idea of a new water, wastewater and environmental protection magazine was raised by a friend.

“Why don’t you launch your own magazine?” he enquired. He knew that both of us had had been editors of W&PC, and that at the time the Davey family worked closely with both the Water Environment Association of Ontario and the Ontario Water Works Association.

It seemed like a good idea and during the first Great Canadian Icebreaker reception at WEFTEC’87 in Philadelphia, we formally announced the launch of Environmental Science and Engineering Magazine. The reaction was most favourable.

The first issue rolled off the press in February 1988 and was immediately embraced by the industry. The first editorial comment by Tom Davey was titled: “Why low-bid systems are bad for the Canadian environment”, a theme that touched a nerve in both consultants and suppliers. This issue also carried an article by Federal Environment Minister Tom

McMillan, which echoed the magazine’s stance on underpriced drinking water.

The first issue also carried an article by Ontario Environment Minister Jim Bradley about the Municipal Industrial Strategy for Abatement (MISA) program. The objective was the virtual elimination of persistent toxic substances entering the environment. It called for strict monitoring and testing programs and resulted in a surge of spending in the environmental industry. Unfortunately, government emphasis on the MISA program was short-lived, when the Liberal Party lost to the New Democrats, in the 1990 election.

The fearsome “hole in the ozone layer”, caused largely by chlorofluorocarbons emissions, dominated the news in the 1980s. ES&E published several articles on methods to recapture CFCs, including some from Dusanka Filipovic, P.Eng., who played an active role in the development of an innovative technology to recapture CFCs from refrigeration and air conditioning equipment when serviced or decommissioned. The ozone layer, which once dominated media coverage, is no longer as newsworthy, since its recovery seems to be well underway.

Throughout the 1980s and 1990s, the “out of sight, out of mind” attitude towards water mains and sewer lines resulted in gross neglect of cleaning, repairing and replacing this infrastructure. In 2001, this attitude changed when eight people died and some 2,000 were made seriously ill from E.coli 0157 contamination in Walkerton, Ontario’s drinking water supply.

When we launched ES&E in 1988, our goal was to make it a voice for Canada’s water, wastewater and environmental protection professionals. Since then, ES&E staff have been extensively involved with, and have won awards from, the Water Environment Federation, the American Water Works Association, Environment Canada, the Water Environment Association of Ontario, and the Canadian Business Press.

Recently, my three-year-old grandson Westley went on a tour of the Duffin Creek Water Pollution Control Plant in Pickering, Ontario, with his dad Peter, who is our managing and online editor. I found it very fitting that 35 years after my father and I founded ES&E Magazine, a fourth generation Davey has now been exposed to the importance of an industry that has been part of our lives for so long.

Steve Davey is the editor and publisher of ES&E Magazine. Please email any comments you may have to steve@esemag.com

Founding editor Tom Davey (centre) with his grandsons Mark (left) and Peter (right) at the 2010 WEAO award ceremony, where Tom was presented with the association’s first annual Geoffrey T.G. Scott Memorial Award.

Westley and Peter Davey at the Duffin Creek Water Pollution Control Plant.

Town of Smiths Falls reducing non‑revenue water losses

By Jason Barlow

The Town of Smiths Falls is a vibrant, progressive single tier municipality with a population of 9,000. One of Eastern Ontario’s most scenic communities, it is centrally located within an hour of Ottawa, Kingston, Brockville and the U.S. border.

The town’s water system serves the residences and businesses in Smiths Falls, as well as a portion of Montague Township. Constructed in 2010, the water treatment plant has a maximum design capacity of 14,000 m3. It provides treated water through a system of approximately 62 km of underground pipes, which range from 100 mm – 550 mm in diameter. These are from 10 to 100 years old and are comprised of various materials, including cast iron, ductile iron, polyvinylchloride, concrete and steel.

Non-revenue water (NRW) is the difference between the volume of water supplied to the system and the volume

of water billed to the customers. It is water loss for which the utility receives zero revenue

A series of water audits conducted in late 2018 began the annual process of calculating Smiths Falls’ NRW. These found that NRW levels were above 60%.

Consequently, the town’s water department began searching for a solution that could be used to reduce its NRW levels

by accurately and efficiently detecting leaks in its water system. In 2019, after a service sustainability review of system operations, the conclusion was to place a priority on NRW and target the system’s water losses to increase efficiency.

Some of the benefits of NRW reduction, in particular leakage reduction, include financial gains from increased water sales/ reduced water production costs, increased knowledge about the distribution system, reduced property damage, reduced risk of contamination, and more stabilized water pressure throughout the system.

The town was repairing four to six watermains annually, and only making repairs when water was surfacing or found within the sewer systems during maintenance activities. In 2020, the town purchased Echologics’ Leakfinder-ST correlation equipment, to assist with the search for areas of concern.

This equipment was chosen since,

A Mueller Hydro-Guard automated flush station.

The town’s water system serves the residences and businesses in Smiths Falls, as well as a portion of Montague Township.

within the water system, 95% of all the leaks/breaks were not surfacing. After the purchase and training on the correlation equipment, the town started surveying areas that were identified as having leak noises. The initial survey was conducted by operation staff with their geophones. These devices consist of a brass disc (puck) connected to a rubber/ plastic tube with ear pieces that are like those on a stethoscope.

While using the correlation equipment, the number of service line leaks increased. During the investigation, the team was able to narrow in on the source of them and make the necessary repairs, or to work with the property owners for repairs made on private portions of the service lines.

Of the 22 watermain breaks and 14 water service repairs completed in 2022, only two of these were identified by surface discharge. All of the other repairs were found utilizing the Leakfinder ST.

Efficiencies were also created utilizing automatic flush stations throughout the distribution system. This allowed the town to remove the old bleeder valves, which would run 24 hours a day 7 days a week. This means more managed flushing of the areas of concern, which increases and establishes a consistent water quality.

While the distribution team was finding and making repairs within the distribution system, the water treatment team was also finding efficiencies in facility operations. These include reduced flows in the systems and enhancing the treat-

ment operation. Reduction in filter backwashes and backwash operations, as well as more consistent UV operation to reduce the amount of cooling water utilized, has led to a reduction of more than 50,000 m3 of process water annually.

Through facility communications and tools such as Google Data Studio, the team has been able to continually track water plant flows and react when a higher flow trend is realized. This increases the effectiveness of leak detection and decreases costs. Repairing a leak before it becomes a break saves rehabilitation costs.

A total of 806,021 m3 of water has been removed from the town’s NRW totals between 2018 and 2022. The average daily flow at the water treatment plant was 6,988 m3/day in 2017. In 2022, the plant saw an average flow of 4,776 m3/

day, which is a reduction of more than 2,000 m3/day over a four-year period. The trend of NRW reduction is continuing in the early months of 2023, as average flow rates of 3,600 m3/day are being realized. This is a savings of another 1,000 m3/day of water loss.

The Town of Smiths Falls has been able to realize energy savings of 300 – 650 kWh/day, along with chemical (coagulant) savings of up to 30,000 kg/ year with the reduction of non-revenue water volumes within its system.

Table 1 – Yearly comparison 2016 – 2022.

Table 2 – Water main breaks/ service leaks repaired (public).

Jason Barlow is with the Town of Smiths Falls. Email: jbarlow@smithsfalls.ca

Toronto’s storm trunk sewer will reduce basement flooding during severe storms

By ES&E Staff

In what is Toronto’s most ambitious basement flooding prevention project to date, city workers have started work on a large storm trunk sewer that will be part of a system to collect, store and move stormwater from the Fairbank-Silverthorn area to Black Creek.

The three-part $380-million project is part of the 2021 council-approved basement flooding protection program and is funded in part by the federal Disaster Mitigation and Adaptation Fund. Following the creation of the new tunnel, workers will install 17 kilometres of new storm sewers and 320 inlet control devices (ICDs) to manage stormwater flow to catch basins.

With major storm events on the rise, the project is expected to reduce basement flooding and sewer backups for more than 4,645 homes across four city wards. It is estimated to reduce 40 million litres of annual combined sewer overflows into Black Creek and other local waterways. The new storm trunk sewer will have the capacity to convey up to 9,500 litres of stormwater per second to Black Creek.

“It is also designed to serve as temporary storage during heavy rainfall and will slow down the release of stormwater to Black Creek,” states a backgrounder on the project.

Overall, the Fairbank Silverthorn Storm Trunk Sewer System project will provide flood protection to a 140-hectare area. The ICDs restrict rainwater from entering the combined sewer system through catch basins, reducing combined sewer overflow and the risk of basement flooding. As a result, the devices may increase temporary surface ponding on streets.

Toronto’s investigation into chronic basement flooding picked up steam in 2010, following an environmental assessment. The city also has a basement flooding protection subsidy program, which offers homeowners a subsidy of up to $3,400 per property to install flood protection devices.

The main tunnel will be created using a Bessac tunnel boring machine that uses rotating disc-shaped cutting wheels to bore through soil and install pipe segments to create tunnel walls. It typically excavates eight to 10 metres per day. Crews will construct a three-kilometre long, 4.5 metre-diameter storm sewer.

The first section of the 270-tonne tunnel boring machine will be lowered into a 40-metre-deep shaft inside Fairbank Memorial Park, located on Dufferin Street south of Eglinton Avenue West. This project is expected to be completed by 2026.

Earlier this year, Toronto officials spent $9 million to rescue a microtunnel boring machine that became ensnared by steel wires while constructing a new storm sewer.

The main tunnel will be created using a tunnel boring machine, pictured. Crews will construct a three-kilometre long, 4.5 metrediameter storm sewer. Credit: City of Toronto

Responding to the Iqaluit water crisis

By Justin Rak‑Banville, Ian Moran, and Dr. Charles Goss

In October of 2021, residents of Iqaluit, Nunavut made water quality complaints regarding a fuel-like smell coming from their tap water. Shortly thereafter, visible fuel-like contamination was discovered on the surface of one of the belowground treated water tanks at the water treatment plant.

The territory’s Chief Public Health Officer issued a "Do Not Consume" water advisory, which placed tremendous stress on consumers for access to potable water, the ability of the hospital to sterilize equipment, and further logistical complications due to the COVID-19 pandemic.

It also prompted a coordinated citywide bottled water distribution program, bottled water supply assistance from the Government of Nunavut, and installation of a temporary water purification system by the Canadian Armed Forces.

A team from WSP was immediately flown to Iqaluit to identify the source of the contamination and address it, assess the risks to consumers, and actively implement measures to safeguard the system from a future contamination event.

One of the major challenges was the remote northern location. During win-

ter months (the time of the crisis), Iqaluit is only accessible by air. Transportation of bottled water, essential goods and equipment is both a costly and untimely endeavour. Further to this, Iqaluit’s harsh winters placed immense pressure on the city to find an alternative to bottled water distribution, as it frequently shuts down due to extreme cold and snow condi-

tions. A solution was needed, and it was needed fast.

As if there were not enough challenges, third-party lab results for petroleum hydrocarbons would take over one week to get back. This meant that critical decisions were being made on week-old data, and the city couldn’t inform con-

continued overleaf…

Visible fuel-like contamination was discovered on the surface of one of the belowground treated water tanks at the Iqaluit Water Treatment Plant.

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sumers of the risks associated with water quality on a daily basis.

In response to this, WSP worked with Aquatic Life Ltd. to install an s::can spectrophotometer from Badger Meter. This technology was relatively new to Canada, and was the first of its kind in Canada’s Northern Territories. WSP professional chemists performed a unique calibration of the device to measure petroleum hydrocarbons. The system could collect and analyze results in real time, which was a vast improvement to the one-week lead time on third-party results.

Additionally, the system can run grab samples. This allowed operations staff to collect results from any point in the water treatment and distribution systems and have results right away. When a water complaint was received by the city, public works staff would collect a sample from the complainant’s tap, and provide the consumer with the results on the same day.

The system also produces a spectrophotometric “fingerprint”, which can be used to compare the likeness between

different samples.

During the investigation, WSP personnel discovered an unusual cave-like structure beneath the water treatment plant. Although the name “the Batcave” had a nice ring to it, the space ended up being called “the Void”. It is essentially the air space between the concrete water treatment plant structure and the surrounding bedrock.

Navigating it was a challenge. Not only was it flooded with contaminated water, but there were also several very narrow corridors and sections with limited headroom. In the deepest reaches of the Void, WSP personnel discovered a severely rusted underground fuel storage tank with remnants of congealed oil hanging from its bottom. Pairing the historic underground fuel storage tank with the vast amount of fuel contamination in the Void, the contamination source appeared to be obvious.

What was not obvious at the time, however, was how the contamination was getting into the water treatment plant, and

how it seemed to accumulate primarily in one tank, known as the North Clearwell. Thankfully, the contamination did not readily pass into the distribution system.

Through a series of in-depth investigative theories and consultations with several professional chemists and subject matter experts, the WSP team identified the pathway and were able to successfully bypass the contamination entry point. Soon after, the pristine glacier-like water quality of Iqaluit was restored.

There were several key stakeholders involved in the project: the City of Iqaluit, the Government of Nunavut, the Federal Government of Canada, the Canadian Armed Forces, and several Indigenous groups. Everyone had the same two questions. Why was an old fuel tank buried next to the water treatment plant? Can it definitively be stated that it was the source of the contamination?

The answer to “why” is embedded in the history of the now 61-year-old plant. The fuel tank was put there during the initial construction to power a pump to be used during a fire emergency. Over the course of several small and large upgrades to the plant, the fuel tank seemed to have been forgotten, and was presumably left full.

Providing evidence that the historic fuel tank was the sole source of the contamination was no easy task, and involved disproving all other potential sources of contamination. WSP inspected every centimetre of the water treatment plant’s heating fuel supply system, all pumps for lubrication leaks, and even went so far as to work with the city on a Phase II Environmental Site Assessment reviewing the soil conditions around the building.

The real backbone of the investigation was the chemical fingerprint analysis from the s::can. WSP personnel collected samples of all liquids and potential contaminants found in the Void, in the water treatment plant, and around the site. The fingerprints provided overwhelming evidence that all contamination was linked back to the historic underground fuel storage tank.

The results from the chemical fingerprinting also provided further validation of the pathway of the contamination into the system. Smaller and more continued overleaf…

volatile compounds were able to penetrate the concrete and contaminate the treated water tanks. Meanwhile, the heavier compounds did not readily pass into the treated water tanks and instead remained as a thick, black liquid at the bottom of the Void.

After providing strong evidence of the source of the contamination and the complex contamination pathway, as well as reasonably disproving all other potential sources of contamination, the “Do Not Consume” water advisory was lifted and consumers were again able to safely drink their tap water.

WSP worked with the city to implement several contamination risk reduction measures, including removing the historic underground fuel storage tank, remediating the contaminant at the bottom of the Void, and installing and calibrating multiple s::can systems.

However, only three months later, in January of 2022, another round of consumer complaints of a fuel-like smell shocked the community. This time, the city was ready. The s::can detected petroleum hydrocarbons and shut the system down immediately, and the city enacted their newly developed standard operating procedures and response plans. This new contamination had a very differ-

ent fingerprint than the contamination a few months earlier, and contained, almost exclusively, thicker and heavier hydrocarbons.

WSP professional chemists and subject matter experts were flown in from across Canada. It was a multi-faceted approach to reassess the system and identify any new or emerging potential sources of contamination.

The team of water treatment, materials, and structural engineers performed a detailed re-inspection of all belowground tanks and noticed right away that something had changed from the previous inspection. Several portions of some of the tank walls had spalled off, revealing a black tar-like substance within.

A sample of the unknown substance was run through the s::can, and the fingerprint was confirmed as a match for the contaminant in the water. Through the team’s review of historical data and documentation, they were able to identify it as a waterstop product that contained petroleum hydrocarbons as an ingredient. When installed properly in a construction joint, the waterstop product poses little to no risk.

In light of the concerns for the waterstop product, WSP worked with the city to remove all remaining waterstop prod-

uct from the concrete tanks, and applied both a protective concrete coating and secondary waterproofing coating to all treated water tanks.

The structural and materials subject matter experts confirmed that the now 61-year-old water treatment plant remains in excellent condition, and remains fit for service for many years to come.

As of November 2022, all upgrades were successfully implemented, and a return-to-service plan was developed and executed. Since the system had been offline for over a year, it was imperative that all valves, controls and automation, and general operation of the facility, remained intact. WSP was on site throughout the entire re-commissioning to ensure a smooth transition for the city and its residents.

A critical component of the project was restoration of the crippled consumer confidence. Consumers had been informed of two fuel contamination events only months apart. On top of that, consumers had to endure almost two full months under the “Do Not Consume” advisory.

WSP delivered several simplified technical presentations to the mayor, city council, and national news media outlets, as well as drafted public service announcements. The city posted water quality information on their website on a regular basis. It also provided residents with access to a water quality hotline and an abundance of additional resources on health risks and the public water system. The successes in restoring consumer confidence were realized through frequent engagement with local public health officials and Health Canada.

While the contamination in one of the tanks at the water treatment plant may have been substantial, it is important to note that the petroleum hydrocarbons that passed into the distribution system did not reach any concentration that would be concerning to any consumer. The rapid responses to both contamination events by the city and WSP likely prevented a much more serious situation.

There was overwhelming evidence that all contamination was linked back to this long forgotten underground fuel storage tank.

Justin Rak-Banville, Dr. Charles Goss and Ian Moran are with WSP Canada. For more information, email: charles.goss@wsp.com

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Finding and fixing sewer inflow and infiltration problems

By Barbara Robinson, Dwayne Grondin and Antonietta Giofu

In 2021, the Standards Council of Canada published a new national sewer guideline, “Developing an Efficient and Cost-Effective Inflow and Infiltration (I/I) Program” (Norton & ICLR, 2021). It conceptually covered many things that need to be considered to address I/I in an existing system.

Since then, Norton Engineering has fleshed out many of the concepts into specific actions to be taken by municipalities to find and fix I/I, now. This article describes some of these actions, none of which require special by-laws or any other changes to be implemented. They have been designed to be actionable immediately, as we already have all the tools needed to reduce I/I in existing systems.

An important concept to understand about addressing I/I is that it is not just an engineering issue. To implement a longterm I/I program, the entire municipality needs to be involved. The work must be supported by the CAO and engineering, development, building, by-law, and planning departments need to participate. Since work with residents is involved, political support is necessary. Engineering staff should take responsibility for demonstrating to senior management the absolute necessity of a long-term I/I program. Cost and risk alone should suffice to convince them.

Although the guideline covers many topics, this article will focus on private side I/I, since this needs to be addressed now.

Experts across North America agree that private side I/I generates 50% – 60% of all the I/I we see at wastewater treatment plants (WWTPs). If we are to reduce I/I and therefore flooding, risk and costs, in the face of more extreme events, we must tackle private side I/I. If we can remove even 30% of I/I, we introduce capacity into our sewers. This means they can convey higher wet weather events and therefore reduce flooding.

This can be achieved without any special tools. But, one of the reasons we have not tackled private side I/I until now, is that municipalities believe their residents will resist these changes. However, if we provide residents with the information that they need to understand why these changes are essential to reduce flood risk and costs to all, we believe there will be substantially more buy-in.

Norton Engineering has been presenting widely to service club groups over the past few years (Probus, Zonta, Rotary), and finds that residents are very keen to help solve these flooding risks, once they understand them.

Private side I/I is illegal in Ontario, since all sewer use by-laws in the province make it an offense to discharge rainwater or groundwater to sanitary sewers. It is important to understand that once I/I (from public or private side) enters the sanitary sewer, it becomes sewage. It cannot be costed dif-

ferently to sewage and should not be.

Our industry needs to start assigning the cost of I/I as the amount we charge to residents on their utility bill. This amount covers all the costs involved, including treatment, staff salaries, benefits and pensions, insurance, costs of flood, etc. Deferral of WWTP expansion is an enormous cost savings that must also be considered.

Here are some simple strategies that we must start implementing, now:

ROOF LEADER DISCONNECTION

Obviously, disconnection of roof leaders is the simplest and least expensive of all the private side I/I fixes, and yet few municipalities have tackled it. Two that implemented such a program are Halton Region and the City of Toronto.

The cost of an average connected roof in Kitchener is $2,000 per house per year (average rainfall x average roof area). This cost is paid for by all existing residents on their utility bill. Furthermore, connected roof leaders obviously contribute substantial peaking of the sewage flow, so contribute directly to flooding when rain events occur.

If even one house is connected, it increases the risk of sanitary sewer backup to all residents, particularly to the neighbours on either side and downstream (depending on hydraulics of course).

Imagine the sanitary sewer is beginning to back up and is just at the threshold of flood. Add a roof leader, with the substantial and peaky flow it discharges and flooding occurs. If we explain this to residents clearly, we may find we get a lot

A sewer cleanout at the property line is an ideal location to look for private side I/I. Credit: VIP Sewer Drain Services

more interest. Indeed, we need to make it socially unacceptable for residents to have connected roof leaders. We can encourage them to check with neighbours to ensure they disconnect.

In a combined system, every roof leader, even those in separated areas, eventually discharges into a combined interceptor at the downstream end of the system before it flows into the WWTP. Combined systems obviously experience more frequent combined sewer overflows (CSOs). Every drop of roof water contributes directly to these CSOs and, in places prone to chronic flooding, to these floods. While we spend trillions on storage, etc. to avoid CSOs, it would be infinitely cheaper and easier to disconnect all roof leaders first.

As stated earlier, municipalities do not need a new by-law, since the sewer use by-law already makes it illegal to discharge rainwater into a sanitary sewer. They simply need a program to identify and enforce connected roof leaders, which can be implemented relatively

inexpensively. Or, a contractor can be hired to do the disconnection.

Connected roof leaders should be made illegal across Canada, through

provincial or federal legislation, to strengthen the message to the public, and assist municipalities in making these changes. Organizations like the Association of Municipalities of Ontario (AMO) could take ownership of this. Let’s educate all residents about the increased flood risk, increased overflows/CSOs, and increased costs that these roof leaders engender, and get them removed, now.

CONNECTED FOUNDATION DRAINS

Obviously, connected foundation drains are another substantial source of I/I on the private side. There are two kinds of foundation drain connections, and they differ markedly:

1. Foundation drains connected at construction, in most older homes constructed before about 1980 when in Ontario, the Ministry of the Environment published the model sewer use by-law that prohibited them. These can be considered legal, non-conforming. That is, they were legal when constructed,

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Cleanout cap off foundation drain in an existing basement. Credit: B. Orr, City of London

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2. Foundation drains connected when residents re-plumb their sump pump. Or, if they remove the sewer cleanout cap so that the water discharges by gravity into their sewer lateral. Plumbers and building inspectors across Canada identify that these are very common. These are clearly illegal.

It is time that we distinguished between these two types and start a program to remove the second kind (sump pumps disconnected, or re-routed). We will eventually need to address the legal, non-conforming type, but let us get started with the easier ones, first.

Now, we already have the means to start tackling illegal foundation drain connections, easily and at very little cost. Every time a building inspector enters a home, they should inspect the basement plumbing and identify these illegal connections. A photo can be taken, and a letter issued to the resident, with a follow up scheduled.

Norton Engineering has been discussing this with building inspectors and plumbers for many years. There is nothing in the building code that prevents an inspector from doing a proactive inspection. As such, there is no legal reason why municipalities cannot direct building departments to adopt this practice. Since the inspector is already there, this represents an efficient and cost-effective means of identifying illegal foundation drains. Obviously, a program must be built around this, likely involving by-law staff, but any framework could be used.

Some municipalities are already proactively protecting residents from harm. In Kitchener, where author Barbara Robinson lives, the utility contacted residents regarding mandatory natural gas meter replacement. While on site to conduct this replacement, the technician inspected her outdoor gas line and determined that it was unpainted.

A letter was subsequently issued her, advising that this pipe does not conform to CAN/CSA-B149, 1-10, Section 6.16.1, which states “outdoor piping or indoor piping and tubing that is exposed to atmospheres that are corrosive to the piping shall be protected by either painting or coating.” She was advised that an

infraction notice will be issued if this is not corrected.

Now, the gas utility concerns itself with resident safety, of course. Basement flooding is also a health and safety issue. Studies now confirm that these incidents can cause PTSD and other longterm health effects. Basement flooding is substantially more common that gas explosions. So, why aren’t we tackling it the same way?

Once a municipality initiates this program and gets it up and running, they can consider how to tackle the legal, non-conforming connected foundation drains. It is always best to implement programs that tackle the low-hanging fruit first, and then evolve it beyond that once it is established.

IDENTIFY PRIVATE SIDE I/I WITHOUT HOUSE ENTRY

Norton Engineering is currently assisting the Town of Amherstburg in implementing the new national sewer guideline. After background review and field investigation, the project team elected to start with a pilot project approach in a 120-home sewer shed.

Peak wet weather I/I is ten times higher than an average day in this area, and it has experienced flooding in the past. The town has cleanouts at most property lines, and in the first pilot area (Ventnor Pilot Area #1).

Originally, house to house basement plumbing inspections were undertaken, with engineering and building staff present. However, Dwayne Grondin, one of the town’s engineering staff, conceived of a solution that does not involve house entry, that is simple and cost-effective. The town is going to bring the cleanouts at property line up to above grade for easy access. Then, during rainstorms, operations staff will open cleanouts and will be able to see directly if there is excess flow coming from the private side.

On this basis, staff will clearly understand which homes are connected and can take corrective action. With the cleanout available, staff can easily return to re-inspect to confirm that necessary works were completed. Currently, the town intends to remove these aboveground extensions, but keeping them is also a good idea so that residents cannot re-connect after conformance.

Obviously, a flow monitor has been installed at the downstream end of the pilot area so that we can track I/I reductions. The project team has already identified a substantial inflow source draining a backyard ponding area that will be addressed.

SUMMARY

Private side I/I makes up more than half of the I/I in our sewer systems. This contributes directly to flooding and costs all residents. It can and should be removed proactively by municipalities, using tools already available to them. This can be achieved efficiently and cost-effectively and should be implemented across Canada. Private side I/I is only one of the many issues tackled in the new national sewer guidelines, which all should read.

Barbara Robinson is with Norton Engineering Inc. Dwayne Grondin, CET, and Antonietta Giofu, P.Eng., are with the Town of Amherstburg. For more information, visit: www.nortonengineeringinc.ca

Illegal re-routing of sump pump water to the sanitary sewer. Credit: B. Orr, City of London

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The benefits of using connected safety devices in water, wastewater facilities

By Julian Jarvis

Every industry has gone, or is going through, a digital transformation, and the water and wastewater industry is no exception. Connected technologies have proven valuable for improving operational efficiency and making regulatory compliance more accessible in many industries.

How we keep our workers safe in the water industry is also evolving. While the safety of workers and facilities is the primary concern, connected devices can provide additional benefits from data collected, such as improving productivity, highlighting trends, and lowering the likelihood of future incidents. From data insights, the water and wastewater industry can avoid unplanned downtime, increase efficiency, and mitigate unnecessary costs.

WHAT IS A DIGITAL WORKSITE?

A digital worksite leverages data from connected Internet of Things (IoT) devices throughout an organization. These insights can help water and wastewater organizations understand where productivity losses or bottlenecks are occurring across their operations. From here, proactive decisions based on real-time information can focus on measures to improve productivity, safety, and profitability.

This can save time during maintenance procedures, help get assets back online faster, and add potentially millions in revenue that otherwise would have been lost.

For example, equipping each worker with a connected safety monitoring device, like the G7 from Blackline Safety, provides valuable data to keep personnel safe throughout the entire facility or out in the field. These wearable devices not only alert users and monitoring personnel to the presence of harmful gases,

but also indicate the location of individuals that need assistance.

But there are additional benefits beyond the immediate safety concerns. The integrated location tracking capabilities of a connected gas detector means that if a worker is exposed to hazardous air, supervisors are alerted in real time of their precise location and the gas levels encountered in the area. This results in a quicker response time and a more prepared response.

Connected gas detectors also record non-alert level exposures. This data can be used to proactively identify possible leaks so that repairs can be done before a serious incident occurs.

There are additional safety needs for lone workers in the field as well as workers in large facilities, such as multi-floor pump stations where tasks put workers beyond sight and sound. Connected devices provide a lifeline for these work-

Equipping workers with a connected safety monitoring device provides valuable data to keep personnel safe throughout the entire facility or out in the field. Credit: APchanel, stock.adobe.com

ers to call for help by pulling an SOS latch, or automatic fall and no motion detection, and missed check-in alarms.

Data analysis can uncover patterns from incidents and highlight areas of safety concerns so that proactive measures can be taken. For example, a high frequency of fall detection alarms in one area of a treatment plant may indicate a water leak is making the area slippery.

If it only happens in the winter, it could be due to a seasonal icy patch that requires a higher traction surface or deicing.

HAZARDS AND RISKS OF CONFINED SPACE ENTRIES

To ensure safe working conditions, confined spaces require both pre-entry and continuous gas monitoring. Blackline’s wearable G7 Multi-Gas Pump detector’s pre-entry mode can be used to sample the air quality of a confined space before access. It can then be put into diffusion mode, to continuously monitor the space while workers complete the job.

The detector can also uncover trends from the data for future confined space work that may indicate unexpected sources of toxic or combustible gases that require additional maintenance.

Deploying area monitors throughout a treatment plant allows safety operators to measure changing atmospheric conditions, even when workers wearing personal gas detectors are not present. Setting up a fence line perimeter ensures the safety of the facility and surrounding areas.

Open path and fixed monitors are limited by location with the need for installation and a direct power source, whereas portable area monitors with a 100+ day battery life have the flexibility to be moved quickly anywhere on site.

If conditions change, a potential hazard is identified, or plant operators want to sample another location, area monitors can be easily moved as often as needed. This flexibility can also benefit wastewater facilities with odour complaints from the public. Operators can

quickly relocate devices in response to air quality concerns with quantitative, real-time data, and then share that information with government agencies as needed via an online dashboard.

CONCLUSION

Connected safety devices accomplish the crucial task of helping to ensure the safety of workers, facilities, and the surrounding areas. But, the data collected can also present additional benefits, such as low-level exposures indicating a leak, facility maintenance issues, and trends to aid confined space work, all with real-time visibility. Ultimately, these insights allow engineering and operations teams to reduce unnecessary costs, improve efficiency, and prevent future safety incidents.

Julian Jarvis is with Blackline Safety whose Canadian office is in Calgary. For more information, email: mirvine@blacklinesafety.com

Report calls for wider use of nature ‑ based solutions for flooding, erosion

By ES&E Staff

The CSA Group has released a new report designed to help governments shift from traditional grey or engineered infrastructure, such as walls and dikes, to nature-based solutions like restoring forests and wetlands, to manage flooding and erosion.

Authored by the Intact Centre on Climate Adaptation at the University of Waterloo, the report reviews watershed management practices within provinces, as well as trends in federal funding for flood risk projects. It also identifies existing best practices and opportunities for improvement when naturebased flood solutions are applied at the watershed-scale.

Floods continue to be the costliest natural disaster across the country. The report, Managing Flooding and Erosion at the Watershed Scale: Guidance to Support Governments Using Nature-Based Solutions, notes that approximately 1.5 million homes, representing 10% of the Canadian residential housing market, are located in high-risk zones where they are ineligible for flood insurance.

“This research supports the addition of new nature-based solutions standards that enhance an already robust set of existing standards to mitigate flood risk,” announced Michael Leering, CSA Group director of environmental and business excellence, in a statement.

“We are encouraged by the growing

momentum at regional levels to adopt new flood resilient standards, and this research is the latest tool to support all levels of government,” Leering added.

Nature-based solutions can contribute to flood and erosion management by storing, slowing and reducing flood waters in the upper and middle watershed, using native vegetation where possible. These solutions can also improve connectivity of watercourses with their flood plains, creating space for water and room for the river. They also preserve and restore sediment processes.

The report has three primary recommendations that CSA Group suggests could be supported by the development of future standards. First, the report

states that it’s important to develop consistent provincial approaches to integrated watershed management, as nearly all provinces other than Ontario focus on habitat quality and biodiversity rather than flood and erosion risk objectives.

Second, the report notes that funding should be prioritized for river flood management of high-risk watersheds, as funding may be directed to municipal governments that often do not have jurisdiction to implement nature-based solutions at the watershed scale.

Lastly, the CSA report suggests that governments should routinely consider nature-based solutions for river flood and erosion management alongside built infrastructure, and should see them as viable long-term strategies with benefits to people and nature. Currently, these options are underutilized, the report’s authors warn. Funding procedures should be updated to more often than not consider nature-based solutions as the “default solution”, they suggest.

“We are seeing increased awareness of the need to work

In 2021, Abbotsford experienced one of Canada’s largest flooding disasters when the Nooksack River overflowed and breached its dike. Credit: edb3_16, stock.adobe.com

EPA asks water utilities to include cybersecurity practices for audits

By ES&E Staff

Cybersecurity protocols must be integrated into audits for U.S. water utilities, says the Environmental Protection Agency (EPA), as it works to clarify definitions and required actions to close cybersecurity gaps that leave infrastructure vulnerable. The periodic audits, often referred to as sanitary surveys, are part of state regulatory requirements to evaluate the adequacy of a facility’s equipment, operation, and maintenance for producing and distributing safe drinking water. The EPA’s latest interpretation clarifies that the regulatory requirement to review the “equipment” and “operation” must include an audit of cybersecurity prac-

tices and controls needed to maintain the integrity and continued functioning of a facility’s operational technology.

If the state determines that a cybersecurity deficiency identified during a sanitary survey is significant, then the state will direct the facility to upgrade its protections, the EPA says.

“Americans deserve to have confidence in their water systems’ resilience to cyber attackers,” announced Anne Neuberger, deputy national security advisor for cyber and emerging technologies on the National Security Council. “The EPA’s new action requires water systems to implement adequate cybersecurity to provide that confidence.”

The clarification comes on the heels of new guidance and a facility survey from the EPA. In the survey, the agency says it found that many U.S. water facilities have “failed to adopt basic cybersecurity best practices and consequently are at high risk of being victimized by a cyber-attack—whether from an individual, criminal collective, or a sophisticated state or state sponsored actor.”

Notably, the EPA already interprets its sanitary survey regulations to require a review of Supervisory Control and Data Acquisition (SCADA) systems, which if attacked, could disrupt the delivery of, or even contaminate, drinking water.

In Canada, cybersecurity for infrastructure is controlled by the Canadian Centre for Cyber Security, or the Cyber Centre. Last spring, the centre issued security considerations for critical infrastructure. In November 2022, Public Safety Canada introduced version two of The Canadian Cyber Security Tool, which operates a self-assessment for facilities.

It “provides the participant with an overview of their organization’s operational resilience and cyber security posture, as well as comparative results across their sector,” says Public Safety Canada.

While Canadian public reporting of cyber-incidents is rare, in March the Department of National Defence confirmed a ransomware attack on a major engineering firm involved with some Canadian military facilities.

In its guidance on the issue of cybersecurity, the EPA has also released Evaluating Cybersecurity in PWS Sanitary Surveys, for public comment.

Later this year, the EPA will offer training for states and water utilities on evaluating cybersecurity in sanitary surveys. Like the guidance, the training will cover approaches to evaluate cybersecurity practices at the facility, including identifying gaps and potential significant deficiencies, actions that could be

employed to address cybersecurity gaps, information protection, available technical assistance from EPA and other public and private-sector organizations, and potential funding.

The EPA has also set up a Cybersecurity Technical Assistance Program for the water sector. Under this program, states and facilities can submit questions or request to consult with a subject matter expert regarding cybersecurity required for sanitary surveys.

Another new resource offered to water utilities is a cybersecurity checklist. It offers tips such as creating sufficiently complex system passwords; requiring multi-factor authentication wherever possible; using unique and separate credentials for users to access OT and IT networks; prohibiting the connection of unauthorized hardware; identifying one role/position/title responsible for cybersecurity within the facility; and creating a written procedure for reporting cybersecurity incidents, including how (e.g., phone call, Internet submission) and to whom (e.g., FBI or other

The U.S. EPA already interprets its sanitary survey regulations to require a review of Supervisory Control and Data Acquisition (SCADA) systems, which if attacked, could disrupt the delivery of, or even contaminate, drinking water. Credit: gen_A, stock.adobe.com

law enforcement, CISA, state regulators, WaterISAC, cyber insurance provider).

For more information, email: editor@esemag.com

Small town of Lumsden leads Saskatchewan with solar‑powered WWTP

By David Nesseth

The scenic Town of Lumsden has achieved an innovative feat by becoming the most solar-driven municipality in Saskatchewan, thanks to its award-winning venture of powering a brand-new wastewater treatment plant with the endless energy of the sun.

With over 2,300 hours of bright sunshine every year, Saskatchewan’s sunkissed landscapes in the Qu’Appelle Valley are a perfect fit for harnessing solar power. And now, Lumsden, an unofficial Regina suburb, has invested $2.7 million for an impressive array of solar panels, powering not just one but four of its municipal facilities to save on operating costs and reduce its environmental footprint.

“We have a lot of sun in Saskatchewan, so let’s take advantage of it,” says Lumsden Councillor Rhonda Phillips, who chairs the wastewater treatment committee.

The strong move to solar secured local officials a first place showing in the solar infrastructure category at the 16th annual Saskatchewan Municipal Awards. Five years of development and planning went into Lumsden’s new solar setup. Now, four arrays of panels help to power a new wastewater treatment facility, two sewage lift stations, and a recycling facility. The solar array for the wastewater treatment plant is a 616 kW array that sits on a setback on town-owned land about the size of two football fields.

Officials have also started to put solar in streetlights to reduce operating costs

Energy savings over the 30-year life of the solar venture are estimated to be more than $2.2 million, while the project will also reduce carbon dioxide equivalents by about 13,100 tons over that time. It contributes to an overall plan of longterm sustainability for the community of

about 2,000 residents.

“Since 2009 we have been working diligently to determine the best solution to reduce our environmental impact,” Phillips said at the groundbreaking ceremony for the new wastewater treatment plant.

Lumsden’s wastewater treatment committee realized that a “tremendous amount of electricity” was going to be used in the operation of a new plant, thanks to blowers, bubblers and pumps, so it settled on a solar approach.

The need for a mechanical facility arose from an inability to expand its 50-year-old small sewage lagoons and keep pace with population growth. The community had also been having infiltration problems with sewer tiles, and had battled flood conditions over several years. Phillips said emergency discharges into an adjacent wetland were necessary during those wet years.

The new $21-million plant designed by Stantec Consulting Ltd. opened in 2022 and uses tertiary treatment that reduces biological oxygen demand, phosphorus and nitrogen compounds. It also has a sequencing batch reactor.

The wastewater treatment plant is required to have zero export to the SaskPower grid, which has restricted the amount of solar power that can go to the plant at times, and has required some fine tuning, local officials said. The community also has 1.2 megawatts in its battery energy storage system so that excess power produced during the day goes to the batteries and can shave peak demand, while also running the plant at night.

The other solar-powered facilities in Lumsden require less energy, so they have smaller panels. The main lift station, which required some site preparation work, uses a 13.8 kW panel system, while the south lift station uses just a 5 kW panel system. The recycling facility requires a 25.4 kW panel system, according to municipal documents.

Some of the funding for the solar project came out of Lumsden’s reserves, a debenture, and $1.1 million from Environment and Climate Change Canada’s Low-Carbon Economy Fund, but there was no provincial contribution.

The community’s first experiment with solar came in 2017 for its River Park Community building, where panels gen-

A local committee said that a “tremendous amount of electricity” would be needed to operate the new WWTP, so it settled on a solar approach. Credit: Humboldt Electric and King Rose Visuals.

erated some 15,000 kilowatts of energy per year. Positive community reception to the concept seemed to propel local officials, said Phillips.

Despite its abundant sunshine, Saskatchewan as a whole is still well behind several other provinces in terms of its sheer volume of solar projects. While Lumsden may currently be blazing a solar path, its larger neighbors are starting to make moves. In April, SaskEnergy announced plans to power the first of many natural gas stations with solar, to run their lighting, heat and control equipment. Don Morgan, Minister Responsible for SaskEnergy, called the move a “major step” towards achieving a 35% reduction in greenhouse gas emissions by 2030.

Alberta is also embracing solar. Last year, EPCOR officially opened the kīsikāw pīsim solar farm, which generates up to half of the energy required to power the E. L. Smith Water Treatment Plant in Edmonton. And, in Calgary in 2017, a 626.7 kW solar addition started to pro-

vide clean drinking water at the Bears-

Energy savings over the life of Lumsden’s solar venture are estimated to be more than $2.2 million. Credit: Town of Lumsden

paw Water Treatment Plant.

David Nesseth is a writer for ES&E Magazine. Email: editor@esemag.com

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Biofilter rehabilitation at Toronto’s Humber Wastewater Treatment Plant

By Justin Gouthreau

The Humber Treatment Plant was originally constructed in 1960 and is Toronto’s second-largest wastewater treatment plant. It services approximately 680,000 residents with an annual capacity of 473,000m3. The facility has undergone extensive upgrades to improve air quality and odour issues, including the biofilters.

The biofilter system consists of a group of concrete tanks which contain biofilter media. Air collected from various locations and buildings at the plant is pumped into the tanks, via a series of ducts, and filtered by the media to reduce odour and emissions.

A recent inspection at the plant determined that the biofilter media had

reached its end of life and required replacement. During the removal of the biofilter media and tank clean-out, it was decided to improve the integrity of the containment. This involved the installation of a geomembrane lining system within the tank, as an added level of protection against any leakage.

Installing a geomembrane liner in a critical containment application within a square concrete tank with corners is particularly challenging and complex. This geomembrane installation required experienced installers who followed a strict installation protocol and QA/QC program.

The contractor working on behalf of the City of Toronto reached out to Layfield for recommendations for a suitable geomembrane to contain the biofilter media in an exposed tank application.

Layfield’s installation team conducted a field evaluation and recommended GeoFlex™ 60 mil (1.5 mm) polyolefin geomembrane as most appropriate for the application to line the three concrete biofilter tanks.

Each biofilter tank measures 8 m x 5 m x 1.4 m. The geomembrane’s prime grade resin and antioxidant formula provide excellent chemical and UV resistance for the required application. In addition, the selected specialty geomembrane provided a high degree of flexibility and elongation to allow for a more efficient installation within the tank edges, corners, and around penetrations.

The installation team lined the concrete biofilter tank with a continuous layer of conductive geotextile, while overlapping the seams to create a continuous conductive surface. Following installation of the

Layfield installer conducting an electric leak location survey using the Arc Test Method ASTM D7953.

geotextile, the geomembrane's seams and penetrations were fusion welded, and the liner was mechanically attached at the top of the tank, using a typical mechanical attachment consisting of an SS316 ¼" x 2" bar and gasket.

Pipe penetrations within the tank were flush-mounted, which presented another challenge as typical pipe boots to seal the penetrations would not be appropriate as they required an exposed piece of pipe to seal around. As a remedy, the installers created a picture frame attachment to seal the liner around the flush pipe penetration and it was compression fitted to the tank to create a dependable seal.

To help ensure there were no leaks in the installed geomembrane, the owner chose to perform an electric leak location survey (ELLS). This was facilitated with Layfield’s Geovolt® geotextile, which provided a conductive layer beneath the non-conductive geomembrane. This allowed the ELLS to find even the tiniest holes. During the ELLS, the technician places a voltage across the geomembrane and identifies any areas where the current flows through the geomembrane, thus identifying a leak.

There are a variety of leak location techniques that can be considered. The Arc Test Method D7953 was chosen for this installation as this method is most appropriate for clean, dry, uncovered geomembranes. During the survey, one electrode is connected to the conductive geotextile below the liner, and a second electrode with high-voltage DC power is introduced above the liner. Where a leak occurs, the circuit is closed, and an arc and audible tone is created to notify the operator of the leak. Arc testing is a reliable and accurate method that can detect leaks smaller than 1 mm in diameter.

To validate the testing procedure, the inspector created an artificial leak within the liner to verify the testing equipment would detect it.

Once the conductive geotextile is installed, it gives the owner flexibility to conduct leak surveys again in the future as part of inspection and maintenance programs. As a secondary function, it also provides a protective layer between the geomembrane and the concrete surface.

Layfield’s team installed the conductive geotextile and the polyolefin geomem brane within five days. The decision to

use the flexible 60 mil geomembrane saved time on the installation and made detail work in the tight corners easily accomplished.

The conductive geotextile performed well, allowing for an efficient and reliable electronic leak inspection. The biofilter rehabilitation at the Humber Wastewater Treatment Plant demonstrated how two

innovative geosynthetic products could work together to deliver reliable containment solutions for wastewater treatment facilities.

Justin Gouthreau is with Layfield Geosynthetics. Email: Justin.Gouthreau@layfieldgroup.com

Installing a geomembrane liner in a critical containment application within a square concrete tank with corners is particularly challenging and complex.

Canada establishes guidelines for boron in drinking water

By ES&E Staff

Health Canada has developed a five milligrams per litre maximum allowable concentration for the chemical element boron in drinking water, according to a recent guideline technical document.

The word “boron” is derived from borax, the mineral from which it was isolated. It can enter the environment from the weathering of rocks and soils and seawater spray, as well as from fossil fuel combustion and wastewater discharge.

Typically, boron is found in pesticides, cosmetics and pharmaceuticals; however, when it comes to water it exists pri-

soaps, detergents and flame retardants.

In most Canadian drinking water supplies, boron is below 0.1 mg/L. It can be higher in groundwater supplies in areas with naturally-occurring boron. Most of the world’s boron is in the oceans with an average concentration of 4.5 mg/L in seawater, while levels in Canadian coastal waters range from 3.7 to 4.3 mg/L.

The main source for Canadians’ exposure to boron is through food; however, exposure through drinking water can contribute up to 16% of total dietary exposure. Health Canada indicates that a treated water concentration of less than 5

“Lower concentrations can be achieved by some drinking water treatment systems, depending on the source water quality, the type of treatment technology in place, and the operational conditions of the treatment plant,” states the technical document.

Of the more than 200 minerals containing boron, only four (borax, kernite, colemite and ulexite) are commercially important and make up more than 90% of the borates used industrially worldwide, according to Health Canada.

“The only significant mechanism expected to influence the fate of boron in water is adsorption-desorption reactions with soil and sediment, the extent of which depends on the pH of the water, concentration of boron in solution, and the chemical composition of the soil,” according to the new guidelines.

The World Health Organization has set a maximum allowable concentration of 2.4 mg/L, while the U.S. Environmental Protection Agency established a non-enforceable lifetime health advisory

In Canada, the maximum allowable concentration is risk-managed to take into consideration the treatment challenges of lowering it for private wells

Reproduction and development are considered to be the most sensitive health considerations for boron toxicity. Boron is not an essential element, but some studies indicate it may be beneficial to human health, and has been used to treat inflammation, arthritis, menstrual pain

This article is intended to be a preview of the legislation and not a replacement for the actual guidance from the government.

For more information, email: editor@esemag.com

Health Canada: Impact of air pollution costs more than $100B annually

By ES&E Staff

Arecent report from Health Canada details the health and financial consequences of exposure to ambient air pollution across Canada. After analyzing outdoor air pollution data spanning 2014 to 2017, the report’s findings suggest that air pollution is responsible for approximately 15,300 premature deaths annually in Canada, resulting in a total economic impact of $120 billion.

Millions of Canadians suffering from symptoms of asthma and acute respiratory syndrome contribute significantly to the economic impacts of air pollution. The $120 billion total economic impact (estimated in 2016) is mainly comprised of premature deaths which account for $114 billion. Non-fatal endpoints, such as emergency room visits, restricted activity days, bronchitis, and asthma, amounted to $5.6 billion.

The pollutants responsible include fine particulate matter (PM2.5), ground-level ozone, and nitrogen dioxide (NO2), according to the report entitled “Health Impacts of Air Pollution in Canada”. “These pollutants are included because there is robust epidemiological evidence of their adverse health impacts, as well as the ability to accurately estimate the spatial distribution of their ambient concentrations across Canada,” the report states.

The report refers to the Global Burden of Disease project, which reveals that air pollution is the fifth leading mortality risk in the world, responsible for 8.7% of deaths globally in 2017, or 4.9 million premature deaths worldwide.

The Health Canada report states that fuel combustion from on-road vehicles and off-road equipment, as well as power generation such as coal or natural gas sources, directly release particles and nitrogen oxides (NOx) into the air. Additionally, combustion emits a suite of organic and inorganic compounds that contribute to secondary PM2.5 and ozone, which is not emitted directly, but formed from precursors such as NOx and volatile organic compounds (VOCs) via secondary reactions in the atmosphere and reactions with sunlight. Natural emissions are also included in Health Canada’s analysis, notably wildfires.

Annual average PM2.5 concentrations for 2015 – 2017 were derived from estimation methods combining remote-sensing observations, chemical transport modelling, and groundbased observations, the report states.

Higher PM2.5 concentrations were found in many of the more populous census areas, such as the Lower Fraser Valley of British Columbia, the Calgary–Edmonton Corridor in Alberta, and along the Windsor–Quebec City Corridor in Ontario and Quebec. The highest concentrations, ranging from 6.7 to 8.8 micrograms, were observed in northern Alberta regions, and southern B.C.

In terms of ozone concentrations, Ontario and Alberta reached levels of 39 to 41 parts per billion, with the highest levels of 42 to 48 parts per billion observed in southern Alberta, the report states. Southern Alberta also had the highest concentrations of NO2, with some areas reaching 7.5 to 12.4 parts per billion.

The estimated background concentrations for Canada are:

• 1.8 micrograms per cubic metre (µg/m3) for PM2.5 (annual average).

• 0.15 parts per billion by volume (ppb) for NO2 (annual average).

• 26 ppb for annual ozone (annual average of daily 1-hour maximum) and 28 ppb for summer ozone (May–September average of daily 1-hour maximum).

When it comes to estimating the economic impact of air pollution, the report considers the potential social, economic and public welfare consequences, including medical costs, reduced workplace productivity, pain and suffering, and other effects of increased health risks. Health incidents include events such as child acute bronchitis episodes and respiratory emergency room visits.

With approximately 63% of the total Canadian population residing in Ontario and Quebec, these two provinces see the heaviest health impacts from air pollution, both in terms of mortality count and premature deaths per 100,000 population. Ontario had the highest number of premature deaths related to air pollution in 2016 with 6,600.

For more information, email: editor@esemag.com

Stock photo of smoke from wildfires blanketing Calgary’s skyline. Credit: Una, stock.adobe.com

Closer to source means faster, clearer results from wastewater surveillance

By David Nesseth

Standing in traffic to get a wastewater RNA sample through a sewer maintenance hole may not be ideal, but it may be more effective, suggests Dr. Banu Örmeci, director of the Global Water Institute and professor at Carleton University, who shared her research at the Toronto Wastewater Surveillance Conference in February this year.

The in-person and virtual event was organized jointly by Ontario’s Wastewater Surveillance Initiative and Toronto Metropolitan University, and brought together renowned experts to reflect on how monitoring expanded during the COVID-19 pandemic, and to predict where the field may be headed.

While logistically, there is a simplicity to obtaining and monitoring samples directly at the wastewater treatment plant (WWTP), easier does not always mean better, explained Örmeci in her conference presentation.

“It’s a bit of a pain,” says Örmeci of moving closer to the source, otherwise known as an upper sewershed monitoring location. “If this is the maintenance hole a sample is needed from, you may find yourself in wild vegetation, or the middle of traffic.”

Wastewater-based surveillance uses wastewater as a representation of all individuals within a sewershed and has previously been used to track the presence of poliovirus, antimicrobial resis-

tance, and illicit drug use.

It takes some initial legwork, but Örmeci says that upper sewershed sampling locations to study viral loads must be selected carefully and considerations must be made around sewer design and hydraulics to get the best results. Testing teams must also consider elements such as sewer pipe connections and layout, flow rates, dilution from stormwater, total pipe distance, and wastewater travel times, known as “residence”.

While a more densely-populated country such as the U.S. may have a median wastewater residence time of 3.3 hours, Canada’s capital city of Ottawa, for instance, can have residence times of up to 36 hours. This is, in part, due to sewer

network design, says Örmeci. “We have the habit of going further and connecting communities that are really too far away.”

The longer wastewater stays in the system, or the further it must travel, the viral signal in it will see some degradation prior to testing. It also introduces more stormwater, ice melt and other sewer sediments to the sample, says Örmeci. This is why going closer to the source can bypass these problems.

Apart from some logistical challenges, there are other clear benefits to sampling viral signals closer to the source as opposed to sampling at WWTPs, Örmeci explained. One study, based in Ohio, has also shown evidence that the age of a sewer system may also negatively impact the quality of a wastewater sample.

One of the most effective approaches that Örmeci has utilized for upper sewershed monitoring is called a nested community approach. She defines it as an area with particular population dynamics, where viral and behavioral trends often happen quicker than some

quieter communities. These communities can often be a good indicator of viral trends in a larger general area, she says.

In one particular study, Örmeci demonstrated how the nested community approach was used to monitor Monkeypox. While the actual name of the community was withheld, she showed how much faster researchers were able to get quality, actionable data compared to sampling at the WWTP.

In May 2022, the upper sewershed monitoring detected Monkeypox 10 days prior to the local health unit’s own findings. For influenza, upper sewershed monitoring showed wastewater signals three weeks prior to the city-documented rise. Lastly, upper sewershed monitoring detected RSV some five weeks earlier than nearby health units.

“It allows us enough time to prepare to take necessary steps,” Örmeci says. Her line graph data from the nested community approach also showed how much stronger the viral signals were compared to the findings from diluted WWTP samples.

“Sampling closer to the communities minimizes the dilution and degradation of the viral genetic material in the sewer and helps us to provide more specific and actionable information to public health officials,” says Örmeci in a follow-up email with ES&E Magazine.

When Örmeci shared her data from the WWTP samples, she analyzed many characteristics of the infrastructure, such as the length of the sanitary and combined sewers, the number of pumping stations, as well as average and maximum flow rates, and the size of the population served.

Örmeci serves on the Strategic Council of the International Water Association. She is also the Jarislowsky Chair in Water and Health at Carleton University, and has earned more than 25 research, teaching and mentoring awards and recognitions.

David Nesseth is a writer for ES&E Magazine. Email: editor@esemag.com

Monitoring runoff helps protect health of Great Barrier Reef

By Ben Ferguson and Shaun Fisher

The Water Quality and Investigations (WQI) team of the Department of Environment and Science for the state of Queensland in Australia manage the long-term Great Barrier Reef and Southeast Queensland catchment loads water quality monitoring programs. These programs span the east coast of Queensland, from the Gold Coast to Cape York (roughly 2,000 km/450,000km2). The programs monitor sediment, nutrients, and pesticides at 81 sites, 35 of which rely on 45 ISCO samplers for the representative collection and preservation of samples.

Sediment, nutrient and pesticide runoff from catchments is contributing to the pressures on marine ecosystems along the Queensland coast, including the Great Barrier Reef and Moreton Bay.

Quantifying the amounts of these constituents in runoff (in both concentration and tonnage) is critical to the effective management of these risks.

This knowledge allows for targeted education around best management practices and opportunities for land use improvement, as well as providing a quantifiable metric to track progress. As these contaminants are largely exported during rainfall runoff events, it is important to obtain high resolution concentration data over these events, which can only be achieved with remotely controlled autosamplers.

CHALLENGES

The main challenges in these programs generally revolve around the remoteness of the monitoring sites and the harsh conditions that the monitoring equipment

are installed in. Some sites are more than a two-hour drive from the WQI’s nearest regional sampling contractor. Other sites are regularly cut off by flood waters for days at a time. In these circumstances, there is no practical way for manual sampling (bottle and pole sampling) to be able to accurately capture a run-off/flood event. This necessitates the use of automated sampling systems.

Because of the on-site conditions, any automatically collected samples also need to be preserved on site (as well as is possible), to ensure their integrity. Ambient air temperatures can be more than 40°C, and up to 55°C inside the monitoring huts (typically a 2x2 m, cyclone rated shed). Humidity also can be extremely high. Samples that are not refrigerated in these circumstances are not considered to

The Daintree River in Queensland is one of many tributaries being tested for sediment, nutrients and pesticide runoff into the Great Barrier Reef along Queensland’s eastern seaboard by the Water Quality and Investigations team.

Above: A hut containing Teledyne ISCO samplers and electronics. Temperatures inside the huts can reach 55°C. Right: The Water Quality and Investigations team of the Department of Environment and Science for the state of Queensland is distributing 45 Teledyne ISCO BLZZRD samplers at 35 sites along the 2,000 km coastline.

be representative of the waterway, and typically are not analyzed.

The primary concern with the equipment is the environment they are installed in. The monitoring huts are ventilated to allow airflow. This means that dust and small animals can find ways into the huts as well. The risk of snakes means that care must be taken when working in them.

High humidity often results in the refrigerated samplers generating large amounts of condensation, on both the inside and the outside of the refrigeration unit. This means that the plug in the base of the sampler must be removed permanently. Otherwise, the sampler fridge can start to fill with condensation. The samplers themselves are kept on a slatted bench, or elevated slightly off the ground, to ensure good drainage of water.

THE SOLUTION

Teledyne ISCO samplers are key to the collection and storage of discrete samples within this system. The WQI have utilized ISCO Avalanche® samplers since 2006 and are now migrating their monitoring programs to 47 ISCO BLZZRD samplers. Forty-five of them are being distributed across 35 locations all along the coast

The WQI have also designed a telemetry monitoring and control system. This system incorporates a datalogger, a Cat M1 modem, river height sensors, acoustic doppler current profilers, real-time water quality probes, in-stream pumps, the ISCO samplers, and power supply systems (solar panels and charge regulators, and lithium or AGM battery banks).

These components all work together, managed by the central data logger to ensure that samples are collected and preserved over the course of a flood event. The timing of discrete samples is automatically informed by a combination of river discharge, level, and real-time water quality parameters, with an option for real-time manual oversight from the WQI office in Brisbane.

Water Quality and Investigations, Dept. of Environment and Science, Queensland, Australia. For more information on Teledyne ISCO, email: darrell.kuta@teledyne.com

Ben Ferguson and Shaun Fisher are with

Balancing environmental responsibility while expanding wastewater management infrastructure

By Mackenzie May

Traditionally, two methods of wastewater management were widely used, and they still are today. In developed areas, gravity fed sewer systems are used to remove wastewater from homes and buildings and deliver the fluid to collection points and treatment facilities.

A gravity sewer system consists of a network of large diameter pipes installed at a continuous downward grade, utilizing the forces of gravity to transport fluids, and lift stations to move fluid to a higher elevation when it is no longer reasonable to excavate deeper.

In areas where sewer infrastructure has not been widely built out, septic sewer systems are used to treat water and dissipate the clean fluid into the surrounding ground, called a leach field, while solids and sludge must be pumped out with a vacuum truck once every three to five years. While each of these technologies have their place, they also have their challenges in a variety of applications.

Pressure sewers offer an alternative sanitary sewer option because they provide an economic solution to challenging environmental conditions, where gravity sewers are impractical and where septic systems pose risks to the environment.

Pressure sewer systems utilize a network of grinder pumps to transport wastewater through small diameter pipes to a collection and treatment system. A grinder pump is a submersible pump designed to reduce the size of solids in wastewater to a slurry that can then be transported for treatment.

These grinder pump stations are located in the yard or basement of each home and wastewater flows into the basin from the building’s sewer line. The basin contains a grinder pump, level sensors, valves and discharge piping. Discharge lines tie into a central line, still small in

diameter, that transports the fluid under pressure to either a collection point or a treatment facility. Pressure sewer systems can range from a handful of pumps and

stations to tens of thousands of pumps and stations, making them very flexible. Environmental impact, accessibility continued overleaf…

From the homeowner’s perspective, a grinder station on their property includes storage capacity for one or two days in instances of power failure and will add only about two dollars per month to an electric bill.

of infrastructure, cost and future development are all considerations that must be taken into account when planning new construction.

The installation of both gravity and septic sewer systems requires major excavation. With gravity fed systems, large diameter pipes must be accurately installed along a continuous downward grade to keep fluid moving at a high enough velocity that solids cannot settle in the line. When lines become too deep for reasonable excavation, lift stations are installed to transport fluid to a higher point of elevation.

Meanwhile, a septic tank installed underground has a capacity of at least 4,600 litres, with a leach field of at least 74.3 square metres.

Since pressure sewer systems are not limited by gravity, wastewater is pumped through small diameter pipes that follow the contour of the land. Piping is installed via directional boring in shallow trenches, located just below the frost line. This allows for minimal installation footprint and expedited environmental recovery.

With a pressure sewer system, wastewater can be transported several thousand metres and can be discharged at a point of higher elevation. As a result, the need for lift stations can be minimized or eliminated in almost every installation. Since directional boring eliminates the need for large trenches, it is possible

Internal layout of a typical residential pressure sewer system. These systems have an average maintenance interval of 10 years.

to install pipe under existing infrastructure such as roads.

This simplifies installation or restoration efforts and costs compared to gravity systems, where existing infrastructure would need to be removed and replaced.

As a closed system, pressure sewers are also protected from risks of leaking, which can contaminate lakes, streams and oceans. A significant concern for failing septic install bases is the poten-

tial for contaminating groundwater with bacteria such as E. Coli, which could be catastrophic for drinking water supplies or could pollute surrounding water in lakeside and ocean-front locations.

GREATER ACCESSIBILITY

For some, accessible wastewater management services mean physically being capable of receiving service. For others, accessible wastewater management services mean having services that a community can afford to maintain and operate. Pressure sewers can help to address both these accessibility concerns.

Since pressure sewer systems can travel long distances and operate in all terrain types, they provide the perfect solution for unique site challenges that builders face with traditional gravity systems. Normally hard-to-service locations include settings which are rocky, hilly, have high water tables, or have long stretches of flat terrain. These installation locations are typically unable to be served by gravity fed sewer systems, due to the network of large diameter sloping pipes that are required.

New developments are not the only place that deserve access to wastewater management infrastructure. There are many small rural communities across Canada that do not have the capital to invest in new or improved gravity sewer systems, which are expensive.

A typical lift station includes a wet well,

screens or grinders for solids, pumps or compressors, valves, power supply systems, alarm and control systems, odour control and ventilation systems. The upfront cost to install a new lift station is typically at least $100,000. This does not account for additional maintenance and operational costs that will be incurred over the life of the system. Some small communities simply cannot afford this.

For many of these small rural communities, septic systems are prevalent. However, septic tanks often only have a life of about 30 years and replacement of a septic tank and leach field is also very costly.

Pressure sewer systems are a solution for septic abatement projects due to low costs, quick installations, minimal environmental disruption and restoration, and easy maintenance and operation. These systems have an average maintenance interval of 10 years.

Grinder pumps are typically designed to require less tools and equipment for troubleshooting and repair compared to the solids handling or chopper pumps found in lift stations. Compared to lift stations, pressure sewer systems do not require the same level of preventative maintenance and inspections.

Pressure sewer systems typically use one common pump design in the entire project, simplifying service and allowing “safety inventory” of repair pumps for instances of pump failure. This allows municipalities to save on both operational and maintenance costs.

The further benefit of pressure sewer systems is allowing developers to defer their upfront installation costs. Rather than installing a costly lift station well in advance of new construction, contractors can simply install the low-pressure sewer pipe up front, and defer the cost of the grinder pump station until the sale of the home. Theoretically, the sewage system can be commissioned the day the new owner takes possession of a home.

Finally, pressure sewer systems help with load management in treatment plants. Septic sewer systems must be pumped out. Trucks bring the waste to a treatment facility, creating an increased treatment load.

Furthermore, in-flow and infiltration are common issues in gravity sewer sys-

tems because they are open to the environment. This drives up cost and inefficiency, as the treatment plant is taking on additional load by treating non-wastewater fluids.

Wastewater treatment plants for pressure sewer systems are less costly to build because the system is closed to infiltration and sizes of solids are minimized. Grinder pumps simplify the treatment process because the wastewater is already ground into a slurry, so solids are eliminated before reaching the plant.

From the homeowner perspective, a grinder station on their property includes storage capacity for one or two days in instances of power failure and will add only about two dollars per month to an electric bill.

PRESSURE SEWERS ALLOW FUTURE GROWTH AND DEVELOPMENT

Pressure sewers are a unique solution because they can be used in new applications and areas without existing infrastructure. They can also tie into existing sewer infrastructure. This helps to “futureproof” areas that may be inclined to experience continued population growth.

Rather than expanding a gravity sewer

system and undertaking a large-scale project that may require significant road construction, the new development can utilize a pressure sewer network and tie that into the existing gravity sewer infrastructure.

The ability to continue to tie into existing systems also means that pressure sewer infrastructure can be built out in phases. Large development projects can take several years for complete construction. If using a gravity sewer system, the complete build-out of sewer infrastructure must be complete before home construction begins. With pressure sewers, large developments can be broken into many phases that ultimately tie together. This allows a developer to defer costs on longer-term build-out, until they have received revenue from earlier phases.

Mackenzie May is with Crane Pumps and Systems. Email: mmay@cranepumps.com

Asset management and diversity, equity and inclusion go hand in hand

ES&E Magazine sat down with Toronto Water and CIMA+ to discuss the City’s incredible diversity, and how asset management is benefiting from, and supporting, diverse organizations and Canada's water sector.

By Peter Davey

It is fitting that a world-class city such as Toronto should host the American Water Works Association’s Annual Conference & Exposition (ACE) in 2023, and the International Water Association’s World Water Congress and Exposition in 2024. Not only is Toronto the country’s largest city, with a population of approximately 3 million, it is also one of the most diverse. Just under half of the city’s residents are immigrants and just over half—52%— are visible minorities.

“Diversity, Our Strength” is the motto of the City of Toronto, and this diversity is reflected in the hardworking professionals who manage the treatment plants and infrastructure that delivers over 1 billion litres of safe, clean drinking water each day to sustain the city and surrounding communities.

“In any organization, the biggest strength is the people—without a doubt,” said William Fernandes, director of water treatment and supply for Toronto Water, during our discussion. “You can’t do anything without people, and therefore our employees are the most important part of Toronto Water.”

Yet, while people are the greatest asset of any organization, especially one responsible with protecting public health and the environment, Toronto Water does have millions of physical assets to manage, and it is required to draw up Asset Management Plans to ensure the life cycle of everything from pumps to valves, and buildings to pipelines, is maximized.

Canada is one of only a few countries in the world to have mandated asset management planning and is recognized by the global community as a leader in this field.

Under Ontario Regulation 588/17 “Asset Management Planning for Munici-

pal Infrastructure”, municipalities across the province are required to have Asset Management Plans (AMPs) in place in order to qualify for infrastructure funding and adhere to the regulation, and importantly, ensure the investments of tax payers are respected.

“Essentially at its core, the Asset Investment/Management Plan is for evidence-based decision-making,” said Vanessa Chau, P.Eng., MIAM, CAMA, senior director – asset management advisory at CIMA+, and the founding member of Asset Management Ontario.

“COVID-19 accelerated the pace and need for asset management and investment planning to stretch each dollar and make sure that water treatment plants and other critical assets are maintained and have their service lives extended,” added Chau.

No matter the size, municipalities across Canada face challenges develop-

ing and updating AMPs, whether due to a lack of resources, the scale and complexity of their infrastructure, or even keeping up with best practices and developments.

As a result, municipalities and utilities rely on consultants to bring in outside expertise, while leveraging global best practices such as ISO 55000 and resources to assist with asset management planning.

One such consultant is CIMA+, a growing Canadian consulting engineering firm, that works extensively with Toronto Water and many other municipalities and utilities.

“We work in partnership with our municipal clients and no matter what the size, it is a true partnership,” said Troy Briggs, executive vice president of infrastructure at CIMA+. “This allows us to bring solutions that consider clients’ site-specific needs and make sure

(left to right) Brian Sudic, Vanessa Chau, and Troy Briggs with CIMA+, and William Fernandes with the City of Toronto, recently spoke with ES&E Magazine about developments in diversity, equity and inclusion, and asset management in the water sector.

that we are providing a sustainable, value-added approach, and not just a cookie cutter.”

By doing this, consultants help clients leverage those assets for many years to come so that the needs of growing communities can be met.

CIMA+, as a recognized corporate member of the global Institute of Asset Management (IAM) is also involved with water and wastewater industry associations. This includes the Ontario Water Works Association, where they are currently working to develop standards that can help smaller municipalities tackle some of the more complicated issues.

“We are constantly trying to give back and help smaller municipalities keep up with changing technology,” said Brian Sudic, vice president of infrastructure – Ontario, at CIMA+.

As the water and environment industry changes, so is the makeup of its workers and member companies, who are recognizing the importance and benefits of supporting diversity initiatives.

Engineering, which has long been primarily a male-dominated field, has seen increasing numbers of female engineering students and professionals in recent decades.

However, according to Engineers Canada, men still “vastly outnumber women in engineering” and the organization has set a goal of raising the percentage of newly licensed female engineers to 30% of the total by 2030.

Chau is a contemporary trailblazer who has helped narrow the gender gap in engineering. She was one of the youngest female inductees into the prestigious Select Society of Sanitary Sludge Shovellers (5S) and was the youngest Water Environment Federation (WEF) delegate to represent Canada.

Recently, she was the only founding member of the IAM –Women in Asset Management – North American board, and she has been nominated to become the Canadian liaison for the IAM’s diversity and inclusion committee.

The IAM is a global association that will be holding its first North American conference in Toronto this October. Chau will also become one of the first “mentors” of the IAM’s global mentorship program.

Chau recalls her experiences as a young professional in the industry and how important it was to have mentors there for support.

“You can imagine that being a young person, it was very, very daunting,” said Chau. “So, mentors like William [Fernandes] and others of the 5S Society who were there for me, and able to guide me, were extremely important.”

Based on her personal experiences and knowledge from working both in Canada and internationally, Chau stresses that men-

torship is integral to diversity, equity and inclusion action plans.

“Especially as a female in the water and wastewater industry, it is critical that we have mentors that have always been there to give us the allyship, sponsorship and guidance, in order for us to succeed,” said Chau.

At an organizational level, CIMA+ is working towards gender parity at all levels of the company to overcome this gender gap, and to deliver better service and expertise to its clients as a result.

In recognition of this, CIMA+ recently achieved bronze certification from the Women in Governance Organization, becoming the first engineering consultant in North America to do so, noted Sudic.

While gender is a key aspect of diversity, equity and inclusion (DEI), it is important to note that diversity extends beyond gender, and includes race, differences in age, physical and mental abilities, and more. Everything that makes up a person lends experience and insight that can improve how organizations are run, and how services are delivered.

For organizations that recognize the benefits of encouraging DEI but do not know where to begin, our group discussion noted some small steps that are easy to take and may offer big results.

These include, but are not limited to: increase women’s representation in leadership development; set targets to internship programs; advertise job openings to specific under-represented groups who may not be aware of them; broaden interview stages to include qualified candidates from diverse backgrounds; and include social and diversity requirements in procurement criteria.

Tying it all together, Fernandes says that asset management and diversity efforts go hand in hand, as both are investments into an organization’s most important resources and tools, and furthermore, help to shape the public sector so that it reflects the public it serves.

“Assets are not just equipment,” said Fernandes. “Assets are humans, and that is where diversity and inclusion come in.”

This sentiment is not unique to Toronto Water or even to Canada. According to Chau, who has spoken at numerous global asset management conferences, the international community agrees that people are at the heart of any successful asset management transformation program and outcomes.

“At its core, for any asset management transformation program to be successful, people are the most critical asset,” said Chau. “It is really about people and diversity, and innovative thinking.”

Peter Davey is the Managing and Online Editor of ES&E Magazine. Email peter@esemag.com

Vanessa Chau belatedly presenting her long-time mentor William Fernandes with the 5S Society’s Golden Shovel. Fernandes was inducted into the society in 2018.

How site remediation can improve long‑term economic success in the NWT

By Tim Chidlaw

The Government of the Northwest Territories’ recent call for input on the benefits of the remediation economy is a welcome initiative, and is working to devise a real strategy for cleaning up abandoned, environmentally-unstable and contaminated sites.

As Canada continues to push larger investments in environment and climate-related actions, on the heels of promises made before the international community at COP27 and COP15 last year, engaging in a broad discussion on how best to approach remediation activities in the North is timely.

The remediation of contaminated sites in the territory usually comes with a significant price tag. For example, the cost of the Giant Mine Remediation Project, budgeted in 2014, came in at a cost of $934 million. A recent update suggests that the cost in today’s dollars could be close to five times that amount, when all costs associated with the project dating back to 2005 are included.

The work will take more than a decade

to complete, with current forecasts suggesting a completion date of around 2038.

There are other challenges to consider beyond the high costs of remediation projects. The current regulatory environment in the territory can, on occasion, be difficult to navigate and bring projects to fruition in a timely manner. To make remediation projects a priority in the NWT, an improved regulatory framework, one that shortens the pre-procurement process and gets boots on the ground months or years faster, would benefit everyone in the region.

There also needs to be a solution for securing the labour force needed to conduct remediation activities. With intense demand for skilled labour in the rest of Canada, the solution would benefit tremendously by being a local one. Providing hands-on training and skills certification for under-employed workers in the region would boost the territory’s economy.

As well, it would provide transferable skills that could be used in other types of environmental and infrastructure work

after the remediation activities are complete.

Partnering with Indigenous communities will be a vital component of any large-scale remediation effort. They can play a role in addressing the labour shortage, and have valuable traditional knowledge. Western science, combined with traditional knowledge, can create the best-in-industry solutions that will be needed for these complex projects.

Once the remediation activities on a given project are complete, the community and region will reap even more economic, social, and environmental rewards.

Further damage to the environment will be halted, allowing ecosystems to recover and allow both plant and animal species to again thrive on the land.

It will also manage the health risks caused by the environmental contamination, which could place a burden on the region’s health care system.

Finally, it will allow for new economic opportunities as people no longer shy away from creating new residential and commercial projects near a formerly contaminated project site.

What is missing from the discussion is the need to ensure that the right technologies and solutions are implemented in these remediation projects. Failure to introduce the right solution can set a project back financially. Many solutions exist for the type of remedial solution required at sites across the Northwest Territories. However, not all of them have been proven in cold weather climates.

Either through advanced testing, or through vetting technologies that already have a proven track record, there will be a real need to ensure that any solution applied to these sites can get the job done in northern climates.

There is a pathway forward for the Northwest Territories to invest in environmental remediation, and reap the rewards that such an investment will create. But it must be done thoughtfully, working with regional and industry stakeholders, and using proven technologies.

Tim Chidlaw is with WSP. For more information, email: tim.chidlaw@wsp.com

Investing in environmental remediation in the Northwest Territories can create many environmental, social, and economic rewards. Photo credit: Yarr65, stock.adobe.com

Thank you to everyone who participated in this year’s CANECT Environmental Compliance and Due Diligence Training Event. We look forward to seeing you at CANECT 2024!

SPONSORS & PARTNERS

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Trinity Consultants

Vector Process Equipment Inc. Wessuc Inc.

Reducing your carbon footprint with heat exchangers

By Matt Hale

Around the world, private companies and government agencies are looking to reduce the greenhouse gas (GHG) emissions associated with their activities, including increasing their use of renewable and low-carbon energy sources, and improving the energy efficiency of their processes.

Energy efficiency represents more than 40% of the emissions abatement needed by 2040, according to the International Energy Agency (IEA) Sustainable Development Scenario. The IEA says: “Energy efficiency is the ‘first fuel’, reining in the scale of this unprecedented challenge, supporting net zero energy goals at lower costs, and delivering a wide array of benefits for society.”

Furthermore, “according to the IEA Efficient World Scenario, currently existing cost-effective technologies are sufficient to double global energy efficiency by 2040.” Heat exchangers are just such

an existing, cost-effective technology. Technologically proven for over a century, developments in materials and design mean that many types of heat exchanger, such as those utilizing corrugated tubes and energy recovery, are now more energy-efficient than ever before.

The biggest efficiency benefits of heat exchangers come about when they facilitate the reuse of as much of the thermal energy generated or used during a process (such as heating, cooling, pasteurization, evaporation, etc.) as possible. Distributing heat more efficiently throughout production facilities has been recognized as a key factor in improving efficiency and reducing GHG emissions in industries, including chemical refining, water treatment and manufacturing.

Many processes require heat, but not all of them utilize all of it. For example, a process using steam at 100°C or more may result in a hot water stream with a temperature of 80°C – 90°C. In some

cases, this will be reheated in a continuous cycle, but, in the least efficient situations, it may simply be dumped, perhaps requiring cooling before it can be discharged.

Water with this temperature profile has a range of potential uses, including pasteurization and low temperature evaporation. Rather than continually heat and then dump process hot water, it makes far more sense to reuse it where possible, by transporting it to where else it is needed in the facility.

HEAT RECOVERY WITH HEAT EXCHANGERS

The first typical example can be seen in food production, if we imagine a product that needs to be pasteurized. The product needs to be heated to the necessary temperature to achieve pasteurization, then rapidly cooled to maintain shelf life and quality. This is achieved using two heat exchangers.

The first uses hot water to raise the temperature, while the second uses chilled water to cool the product down again. In the second process, the temperature of the cooling water is increased significantly.

There are three options for dealing with this heated water: discard or discharge it elsewhere; cool it again for reuse; or cool it again for reuse but use some of the heat it contains towards the heat required for the pasteurization phase. This third option utilizes heat recovery or heat regeneration, reducing the amount of new energy required for the subsequent first heating phases.

A second example shows how heat left over from one process can be recaptured to be used elsewhere. Many anaerobic digestion (AD) plants use heat exchangers to pasteurize the digestate produced during the AD process, so that it can be sold as an agricultural fertilizer. The “surplus” heat which is generated after the system has been running for two hours is used to preheat the digestate, reducing total heat load. Overall plant efficiency is improved by increasing the amount of generated energy, which is available for export or other uses, as opposed to being required for pasteurization.

Finally, combining multiple heat exchanges can often provide the greatest energy benefits, for example, in a multi-ef-

Heat exchangers can play a key role in reducing greenhouse gas emissions.

fect evaporation system such as the HRS DCS digestate concentration system.

This uses heat exchangers and evaporation to reduce the volume and increase the concentration of sludges and digestate.

The first evaporation stage heats liquid digestate and uses a cyclone separator. The steam produced from this first cycle (usually available at 70°C) is then used as the heating media for the second effect, whereby the process is repeated.

The subsequent steam (usually available at 60°C) is then used as the heating media for the third cycle. The number of effects is determined by the level of dry solids required and the amount of surplus heat available, up to a maximum of four cycles. After the final stage, the steam is condensed back to water and this heat is used to pre-heat the incoming product before the first stage of evaporation.

Heat recovery is not limited to systems dealing with liquids. HRS recently supplied a large G Series gas-to-gas heat exchanger to recapture heat from the high temperature exhaust gases leaving a large chemical reactor. This recovered heat is then used to help pre-heat the chemicals entering the reactor to around 500°C. As well as helping to improve energy efficiency at the plant, the new unit has been designed to cope with challenging operating conditions in order to provide a suitable working life.

These examples show that where the situation allows, heat exchangers have significant potential to reduce the energy

consumption (and therefore GHG emissions) of thermal processes in a wide range of industries. The capital costs of including energy recovery in a heat exchanger system is likely to be higher than similar systems without heat recovery. But, these will be recovered over the working life of the unit, particularly at today’s high energy prices.

Matt Hale is with HRS Heat Exchangers. For more information, visit: www.hrs-heatexchangers.com

Heat recovery can be applied to gases as well as liquids.

Whitehorse weighing move to multi‑ barrier drinking water treatment

By ES&E Staff

The City of Whitehorse’s water experts say additional treatment processes and disinfection are necessary for their drinking water as its quality has slowly degraded due to the influence of surface water over time. But the upgrade is estimated to cost $39 million and Whitehorse has no funding in place for the project, which would need to be undertaken within the next five years, prior to the renewal of the city’s water license.

The city withdraws and chlorinates all of its drinking water from the Selkirk Aquifer’s seven production wells. Currently, the city is only equipped to treat and distribute groundwater.

According to a staff report, over the past few years, the city has detected changes in the quality of the groundwater source. The changes observed indicate that the Selkirk Aquifer is likely under the influence of groundwater under the direct influence of surface water (GUDI).

Based on regulations under the Yukon’s Public Health and Safety Act, if a drinking water source is in contact with groundwater, then additional treatment processes, as well as disinfection, are required.

“The risk of not proceeding with the project could adversely impact the ability of the city to provide safe and quality drinking water to its customers,” continues the staff report. “Boil water advisories could become prevalent and trying to implement a rushed solution would be costlier and more challenging than implementing a proactive solution.”

Council had a number of questions for city staff about the recency and certainty of “live hit” findings of contamination. They wondered if more research should be completed to confirm the need for additional treatment barriers.

Mike Firlotte, the city’s water and wastewater services manager, told council that the husk of a Giardia cell was found in 2018, but may not be related

to surface water contamination. The groundwater could also be experiencing different pH, ions or metals due to contact with surface water, he said.

“We see a fingerprint of groundwater and we see a fingerprint of surface water, and when we see that blending that means there could be evidence of infiltration,” Firlotte told council.

In 2022, Whitehorse staff completed a pre-design report to identify potential upgrades to the current groundwater treatment system at the Selkirk Pumphouse. A multi-barrier treatment system was recommended.

A staff report before the city’s corporate services committee states that completion of the recommended upgrades would provide the ability to withdraw water from both the Selkirk Aquifer and Schwatka Lake, allowing the City of Whitehorse to have a “robust supply of drinking water”.

City staff said they “simplified” their recommendations based on current

regulations. For instance, they are now suggesting a level two instead of level four environmental operators’ certification for the plant. The system would be easier to operate, and simplify the hiring process for operators. Also, existing city operators with level one certification would transition more easily into the required level two for the upgraded treatment plant, the staff report stated.

The additional treatment processes would also raise annual operation and maintenance costs by $1.2 million over the current $2.1 million, and a rate increase would be required once the facility is in operation. The current design budget for the new treatment is $2 million and funding has been approved for design.

City staff were asked to come back to council and provide additional information about some of the potential risks to the current system.

For more information, email: editor@esemag.com

Whitehorse currently withdraws and chlorinates all its drinking water from the Selkirk Aquifer’s seven production wells. Credit: Scalia Media, stock.adobe.com

Understanding the basic principles of water treatment media pilot trial design and evaluation

By Neal E. Megonnell

There are many methods to evaluate the use of activated carbon and other media for water treatment. These include a simple adsorption model, an adsorption isotherm, or a laboratory mini-column study, such as the rapid small scale column test (RSSCT). While these approaches can generate some valuable initial data, each comes with limitations.

Initial screening using these methods can provide a starting point, but to overcome their limitations, a pilot scale study conducted at the site is the best method. Properly designing, operating, and analyzing data from a pilot trial will yield valuable performance data, as well as other information that can be used to anticipate full-scale operation.

PILOT COLUMN DESIGN CONSIDERATIONS

A pilot column should be operated with the surface loading rate and empty bed contact time (EBCT) identical to the full-scale operation, regardless of media selection. These calculations are simple, knowing the full-scale flow rate and size of the adsorption vessel being used.

In the case of a 12-foot diameter vessel treating 500 gpm, the surface loading rate is determined by dividing the flowrate by the surface area of the vessel. In this case, a 12-foot diameter vessel has a 113 ft2 surface area. Therefore, dividing the 500 gpm flow rate by 113 gives a surface loading rate of 4.4 gpm/ft2.

Many bid specifications for large eight, 10, and 12-foot diameter vessels will include a reference to 20,000 lbs of carbon. The 20,000 lbs number comes from carbon products that have an apparent density of 0.5 g/cc.

Depending on the activated carbon being tested, the apparent density can range from 0.35 g/cc to over 0.6 g/cc. It is

important to use the desired empty bed contact time in the full scale, to determine the volume of activated carbon required in the full scale and pilot system.

Again, assuming 500 gpm, and an empty bed contact time of 10 minutes, 5,000 gallons or approximately 670 ft3 of activated carbon would be required for the full scale. Knowing the density of the product then allows the weight of the activated carbon to be determined. The effect of the apparent density can result in a wide range of carbon weight.

Pilot units exist in various forms and configurations. For flexibility, it is best to have a pilot column unit capable of testing multiple products at the same time and be able to cover a wide range of surface loading rates and empty bed contact times.

Knowing the diameter of the pilot

scale columns, as well as the full-scale surface loading rate and empty bed contact time, allows for the calculation of the pilot scale flow rate and amount of activated carbon or other media. Assuming a 4" inside diameter pilot column, 4.4 gpm/ft2 and 10-minute empty bed contact time, a flow rate of 0.4 gpm and 4 gallons or 0.5 ft3 of activated carbon are required.

ACTIVATED CARBON PREPARATION

Dry activated carbon as received, contains gas within its pore structure that must be removed by wetting the activated carbon prior to use. Water temperature and time have large effects on how quickly the activated carbon will wet, as do other properties such as carbon type and surface properties.

Once the activated carbon is dry loaded into the pilot column, wetted, and soaked for 24 hours, the column is ready for backwash to remove fine particles and stratify the activated carbon particles by size and density. The backwash rate is determined by product and temperature.

PILOT UNIT OPERATION AND DATA COLLECTION

Once the activated carbon, or other media, has been properly prepared, the columns are ready for downflow operation and data collection. Many pilot units are operated without taking full advantage of the amount of data that can be collected. Most pilot trials simply analyze the effluent concentration from the columns without using the opportunity to sample for other parameters that may be very important for initial startup and long-term operation. The pilot unit should be monitored for the following parameters:

• Activated carbon virgin carbon properties;

An eight-column pilot scale unit. Pilot trials of water treatment media can generate extremely valuable data when tests are properly designed and data is carefully analyzed.

• Influent and effluent pH;

• Influent and effluent metals of interest such as arsenic and antimony;

• Breakthrough profiles for identifiable and measurable compounds;

• Pressure drop during operation;

• Non adsorbable total organic carbon (TOC) fraction;

• Potential biological activity specifically with biologically degradable compounds.

DATA ANALYSIS

Effluent water quality data can be used to determine the duration of certain events, such as the increase or spike in the pH in duration and magnitude, the duration and magnitude of target metals leaching, and breakthrough of specific compounds as well as aggregate measurements such as TOC.

The breakthrough curves can be analyzed for obvious specific events, such as the initial point of breakthrough and the point of breakthrough at which the treatment objective is exceeded, but a fully developed breakthrough curve can lead to far more valuable data.

A single compound breakthrough curve that is fully developed can be used to determine the length of the mass transfer zone. This calculation will show the portion of the activated carbon bed that is utilized, and can be used to design full-scale systems that fully utilize the adsorbent capacity.

It is also possible that individual compounds with concentrations below the treatment objective may exhibit what is known as “roll over”. This is a phenomenon that exists in an activated carbon adsorption system where a more strongly adsorbed compound will force a weakly adsorbed compound to desorb and show at higher concentrations in the effluent when compared to the influent.

POST PILOT TRIAL ANALYSIS

A great deal of information can be obtained from a pilot trial that cannot be determined by modelling, isotherm, or mini-column testing. Aside from the obvious parameters outlined previously, more valuable information can be obtained after the pilot trial by analyzing the spent activated carbon utilized during the trial.

Spent carbon should be analyzed for parameters such as iodine number, ash content, and can also be utilized for labscale reactivation to determine the feasibility of reactivation and potential reuse.

CONCLUSIONS

Although adsorption modelling, isotherms, and mini-columns can generate valuable data, the limitations associated with each method leave many questions that can only be answered by conducting a properly designed pilot column.

With our limited knowledge of emerging contaminants, such as the growing list of PFAS compounds, endocrine disrupting compounds, and improving detection limits for well-known compounds, pilot trials can generate the highest quality data. These also generate side-by-side data not only with similar products, but in the case of PFAS compounds, various existing and experimental products.

It is important to properly design and operate the pilot unit to ensure the data will ultimately represent the fullscale operation. It is also imperative to analyze all media, both before and after testing, to ensure the media is representative of actual production and that the used media can be either reused or properly disposed.

Pilot trials can generate extremely valuable data when tests are properly designed and data is carefully analyzed. Bad inputs yield bad outputs, so spend the time to properly design the pilot, and outline and review what is being analyzed, as well as the overall goals.

Neal E. Megonnell is with AqueoUS Vets. For more information, visit: www.aqueousvets.com

Table 1. Effect of apparent density on carbon weight in fixed volume.

Research projects blaze trails at Canadian colleges and universities

By ES&E Staff

Canadian colleges and universities made headlines this spring with an array of innovative and meaningful research projects. From mapping sea ice with artificial intelligence in Waterloo, to using datadriven flood solutions to safeguard Calgary, ES&E offers a snapshot of some of the impactful work already underway at nine schools across the country.

ALBERTA

The City of Calgary’s River Engineering team provided the Southern Alberta Institute of Technology’s second-year Integrated Water Management students Aidan Yakymyshyn and Dawson Smethurst with four different spatial geographic information system (GIS) datasets for the students’ final major project.

The students were able to use GIS to identify local communities susceptible to potential pipe backups due to flooding. They recommended stormwater outfall upgrades such as the installation of water flow control devices in flood-prone areas.

“The potential cost of damages in the absence of these valves could be three times the cost of installing the valves,” says Smethurst.

Also in Alberta, the University of Calgary researchers behind the successful COVID-19 wastewater monitoring program and online COVID tracker have received $5 million in new funding to use their wastewater testing platform to study and develop monitoring for other pathogens.

Dr. Casey Hubert, professor of geomicrobiology in the Faculty of Science, says that “developing additional versatile methods that cover a wide range of genomic targets will better prepare Alberta Health for contending with future epidemics, pandemics and even endemic disease using wastewater monitoring.”

SASKATCHEWAN

Saskatchewan Polytechnic’s Integrated Resource Management program student Tucker James, who spent last summer on Prince Albert National Park’s resource conservation team, wants to expand the presence of pollinator gardens.

During the second year of his diploma program, James decided to further his knowledge of pollinator gardens, which he says teach people about the native ecology in Saskatchewan, and the importance of growing native plants and providing resources for species at risk.

“The main focus is creating a habitat that is beneficial to local native species such as butterflies, hummingbirds and moths,” says James, who plans to further his education at the University of Regina, majoring in environmental biology. He pitched his pollinator garden idea to the City of Prince Albert, which resulted in a partnership. James received

ONTARIO

Earlier this year, a remote sensing research team from the University of Waterloo won an international competition aimed at mapping sea ice. Waterloo Engineering and the Vision and Image Processing (VIP) Lab within the Department of Systems Design Engineering partnered to develop an AI model based on a multi-task deep convolutional neural network to retrieve parameters from multi-sensor satellite data. They used advanced AI techniques such as spatial-temporal encoding, domain adaptation and multi-task learning to boost the performance of the model.

Dr. Xinwei Chen, a UWaterloo postdoctoral researcher, says that the team’s success “motivates us to continue to have worldwide impact in future research

a 23 m2 plot for his garden from the Prince Albert Food Bank.

Southern Alberta Institute of Technology’s Dawson Smethurst holding up a stormwater flow control device. Credit: Southern Alberta Institute of Technology

concerning the combination of AI and remote sensing.”

Canadore College in North Bay has launched its Clean Water Initiative with the opening of a Water Teaching Lodge named Mshibizhiwgamig, which means Great Lynx Lodge. The lodge and the construction of an operational water treatment facility on campus will provide a new approach to clean water and technology that prioritizes Indigenous teachings about water.

“The lodge is a collaboration between Canadore and the private sector to be a catalyst for change,” says Shawn Chorney, Canadore’s VP of strategic infrastructure, Indigenous and learner services. “We need to offer new, custom solutions for water so we’re not perpetuating existing

toria to study climate solutions for rural, remote, and Indigenous communities in B.C.

With the aid of $1 million from the Pacific Institute for Climate Solutions, the research partners will spend four years “preparing communities, people and economies for the coming climate impacts,” says Nancy Olewiler, a professor in SFU’s School of Public Policy.

Project leaders note that the initiative’s success depends on pairing technical knowledge from partner organizations with local knowledge among rural, remote and Indigenous communities.

While people living in urban centres are experiencing the effects of climate change through heatwaves and extreme rain, their remote and rural counterparts

(NEI) research program at Yukon University has received $5.5 million in funding to assess the realities, challenges and barriers surrounding clean energy options in a northern environment. It is one of seven research programs at the YukonU Research Centre.

NEI is partnering with the University of Toronto (UofT) and the University of Victoria (UVic) for two new research projects. With UofT, the teams will study how carbon capture and storage technologies might be effectively integrated into remote northern communities.

With UVic, there will be a multi-disciplinary initiative focused on offshore technologies to promote the transition of clean energy in small, remote communities in the North.

COLLEGES, UNIVERSITIES, RESEARCH CENTRES & TRAINING

The following institutions offer post-secondary education in fields relating to water, wastewater, environmental protection and environmental remediation. Also included in this guide are research centres affiliated with Canadian universities, and training companies.

Mohawk College

COLLEGES

ɗ ALBERTA

Keyano College

Fort McMurray

www.keyano.ca

Lakeland College

Vermillion, Lloydminster www.lakelandcollege.ca

Lethbridge College

Lethbridge

www.lethbridgecollege.ca

Medicine Hat College

Medicine Hat

www.mhc.ab.ca

Portage College

Lac la Biche

www.portagecollege.ca

Southern Alberta Institute of Technology

Calgary

www.sait.ca

ɗ BRITISH COLUMBIA

British Columbia Institute of Technology

Burnaby

www.bcit.ca

Camosun College

Victoria

www.camosun.ca

Douglas College

New Westminster

www.douglascollege.ca

Okanagan College

Kelowna

www.okanagan.bc.ca

ɗ MANITOBA

Assiniboine College

Brandon

www.assiniboine.net

Red River College

Winnipeg

www.rrc.ca

ɗ NEW BRUNSWICK

New Brunswick Community College

Miramichi

www.nbcc.ca

ɗ NEWFOUNDLAND AND LABRADOR

College of the North Atlantic Corner Brook cna.nl.ca

ɗ NORTHWEST TERRITORIES

Aurora College

Various

www.auroracollege.nt.ca

ɗ NOVA SCOTIA

Nova Scotia Community College Various www.nscc.ca

ɗ NUNAVUT

Nunavut Arctic College Various www.arcticcollege.ca

ɗ ONTARIO

Algonquin College

Ottawa www.algonquincollege.com

Cambrian College Sudbury

www.cambriancollege.ca

Canadore College North Bay

www.canadorecollege.ca

Centennial College

Toronto

www.centennialcollege.ca

Conestoga College

Kitchener www.conestogac.on.ca

Confederation College

Thunder Bay www.confederationcollege.ca

Durham College

Oshawa www.durhamcollege.ca

Fleming College

Lindsay www.flemingcollege.ca

Georgian College Barrie www.georgiancollege.ca

Loyalist College

Belleville www.loyalistcollege.com

Hamilton www.mohawkcollege.ca

Niagara College Canada

Niagara-on-the-Lake www.niagaracollege.ca

Northern College

Various www.northernc.on.ca

Sault College

Sault Ste. Marie www.saultcollege.ca

Seneca College

Toronto

www.senecacollege.ca

Sheridan College

Oakville www.sheridancollege.ca

St. Lawrence College

Cornwall www.stlawrencecollege.ca

ɗ PRINCE EDWARD ISLAND

Holland College Charlottetown www.hollandcollege.com

ɗ QUEBEC

Cégep de Saint-Félicien Saint-Félicien www.cegepstfe.ca

John Abbott College

Montreal www.johnabbott.qc.ca

Vanier College Montreal www.vaniercollege.qc.ca

ɗ SASKATCHEWAN

Luther College Regina www.luthercollege.edu

Saskatchewan Polytechnic Various www.saskpolytech.ca

ɗ YUKON

Yukon University - Diploma and Certificate Programs

Whitehorse www.yukonu.ca

UNIVERSITIES

ɗ ALBERTA

Concordia University of Edmonton

Edmonton www.concordia.ab.ca

Mount Royal University

Calgary www.mtroyal.ca

The King’s University

Edmonton www.kingsu.ca

University of Alberta Edmonton www.ualberta.ca

University of Calgary Calgary www.ucalgary.ca

University of Lethbridge Lethbridge www.uleth.ca

ɗ BRITISH COLUMBIA

Kwantlen Polytechnic University Various www.kpu.ca

Royal Roads University

Victoria www.royalroads.ca

Simon Fraser University Vancouver, Burnaby www.sfu.ca

Thompson Rivers University Kamloops www.tru.ca

University of British Columbia Vancouver, Kelowna www.ubc.ca

University of Northern British Columbia Prince George www.unbc.ca

University of Victoria Victoria www.uvic.ca

ɗ MANITOBA

Brandon University

Brandon www.brandonu.ca

Canadian Mennonite University Winnipeg www.cmu.ca

University of Manitoba

Winnipeg

www.umanitoba.ca

University of Winnipeg

Winnipeg www.uwinnipeg.ca

ɗ NEW BRUNSWICK

Mount Allison University

Sackville

www.mta.ca

Université de Moncton Moncton

www.umoncton.ca

University of New Brunswick

Fredericton www.unb.ca

ɗ NEWFOUNDLAND AND LABRADOR

Memorial University of Newfoundland

St. John’s, Corner Brook www.mun.ca

ɗ NOVA SCOTIA

Acadia University

Wolfville www.acadiau.ca

Cape Breton University

Sydney www.cbu.ca

Dalhousie University

Halifax www.dal.ca

Saint Mary’s University

Halifax

www.smu.ca

St. Francis Xavier University

Antigonish www.stfx.ca

University of King’s College

Halifax www.ukings.ca

ɗ ONTARIO

Brock University

St. Catharines www.brocku.ca

Carleton University

Ottawa

www.carleton.ca

Lakehead University

Thunder Bay, Orillia

www.lakeheadu.ca

McMaster University

Hamilton

www.mcmaster.ca

Nipissing University

North Bay

www.nipissingu.ca

Ontario Tech University

Oshawa www.ontariotechu.ca

Queen’s University

Kingston www.queensu.ca

Redeemer University

Ancaster www.redeemer.ca

Toronto Metropolitan University

Toronto

www.torontomu.ca

Trent University

Peterborough www.trentu.ca

University of Guelph Guelph www.uoguelph.ca

University of Ottawa

Ottawa www.uottawa.ca

University of Toronto Toronto www.utoronto.ca

University of Waterloo Waterloo www.uwaterloo.ca

University of Windsor Windsor www.uwindsor.ca

Western University London

www.uwo.ca

Wilfrid Laurier University

Waterloo www.wlu.ca

York University Toronto www.yorku.ca

ɗ PRINCE EDWARD ISLAND

University of Prince Edward Island

Charlottetown www.upei.ca

ɗ QUEBEC

Concordia University

Montréal www.concordia.ca

Polytechnique Montréal

Montréal www.polymtl.ca

McGill University

Montréal www.mcgill.ca

Université de Montréal

Montréal www.umontreal.ca

Université de Sherbrooke

Sherbrooke www.usherbrooke.ca

Université du Québec Various www.uquebec.ca

Université Laval Québec City www.ulaval.ca

ɗ SASKATCHEWAN

First Nations University of Canada Regina www.fnuniv.ca

University of Regina Regina www.uregina.ca

University of Saskatchewan

Saskatoon www.usask.ca

ɗ YUKON

Yukon University

Whitehorse www.yukonu.ca

R&D CENTRES

Advancing Canadian Wastewater Assets

University of Calgary

www.ucalgary.ca/acwa

Annacis Research Centre

Delta, B.C.

www.annacisresearchcentre.ca

Brace Centre for Water Resources Management

McGill University

www.mcgill.ca/brace

Canadian Rivers Institute

University of New Brunswick

www.canadianriversinstitute.com

Centre for Advancement of Trenchless Technologies

University of Waterloo www.catt.ca

Centre for Environmental Engineering Research and Education

University of Calgary www.schulich.ucalgary.ca/ceere

Centre for Water Resources Studies

Dalhousie University www.centreforwaterresourcesstudies. dal.ca

ECO Canada

www.eco.ca

Global Institute for Water Security

University of Saskatchewan water.usask.ca

Global Water Institute

Carleton University

www.carleton.ca/gwi

Ontario Rural Wastewater Centre

University of Guelph

www.ontarioruralwastewatercentre.ca

Ontario Water Consortium

www.ontariowater.ca

Pacific Water Research Centre

Simon Fraser University

www.sfu.ca/pwrc

Pulp and Paper Centre

University of British Columbia

www.ppc.ubc.ca

Research and Technology Institute

Walkerton Clean Water Centre

www.wcwc.ca

The Beaty Water Research Centre

Queen’s University, Royal Military College of Canada

www.waterresearchcentre.ca

The Centre for Advancement of Water and Wastewater Technologies

Fleming College

www.cawt.ca

Urban Water Research Centre

Toronto Metropolitan University

www.torontomu.ca/water

Water & Climate Impacts

Research Centre

University of Victoria

www.uvic.ca/research/centres/wcirc

Water Institute

University of Waterloo

www.uwaterloo.ca/water-institute

TRAINING PROVIDERS

Accessible Water & Wastewater Solutions Ltd. Atlantic Canada

www.awws.ca

Acute Environmental & Safety Services

Waterloo, ON N2V 2J4

Tel: 519-747-5075

info@acuteservices.com

www.acuteservices.com

ACUTE is committed to partner with our customers to exceed corporate and legislative requirements by providing our services from motivated and knowledgeable people. ACUTE assists our customers with health and safety services for more than just legal compliance, but to help their employees stay safe and work successfully. ACUTE believes in developing strong partnerships with our clients to ensure that we are meeting their health and safety requirements and exceeding their corporate safety goals.

Alberta Water & Wastewater Operators Association

Alberta

www.awwoa.ca

Associated Environmental Site Assessors of Canada

Canada

www.aesac.ca

ATAP Infrastructure Management

Saskatchewan

www.atap.ca

Atlantic Canada Water & Wastewater Association

Atlantic Provinces

www.acwwa.ca

BC Water & Waste Association

British Columbia

www.bcwwa.org

Canadian Association for Laboratory Accreditation

Canada

www.cala.ca

Canadian Water Quality Association

Canada

www.cwqa.com

Colleges and Institutes Canada

Canada

www.collegesinstitutes.ca

ECO Canada

Calgary, AB

www.eco.ca

Environmental Training Institute

Atlantic Provinces

www.etivc.org

IBI Group

Ontario

training.ibigroup.com

Keewaytinook Centre for Excellence

Ontario

www.watertraining.ca

Manitoba Water and Wastewater Association

Manitoba

www.mwwa.net

North Shore Micmac District Council – Circuit Rider Training

New Brunswick

www.nsmdc-crtp.com

Ontario Clean Water Agency

Ontario

www.ocwa.com

Saskatchewan Polytechnic

Saskatchewan

www.saskpolytech.ca

Team-1 Academy

Ontario

www.team1academy.com

Walkerton Clean Water Centre

Ontario

866-515-0550

519-881-2003

inquiry@wcwc.ca

www.wcwc.ca

The Walkerton Clean Water Centre (WCWC) is an agency of the Government of Ontario, established in 2004, to ensure clean and safe drinking water for the entire

province. WCWC coordinates and provides education, training and information to drinking water system owners, operators and operating authorities, and the public, in order to safeguard Ontario’s drinking water. Through partnerships, WCWC also provides training for the 134 First Nations communities in Ontario.

World Water Operator Training Company

Ontario

www.wwotc.com

Quality Service since 2002

In-house Engineering

In-house 3D Drafting

In-house Machine Shop

Service and Repair

Field Services

Preventative Maintenance Program

Welding and Hard Surfacing

Dynamic Balancing In-house

Parts Inventory

FLARE FITTING FOR VENTED BALL VALVE

Asahi/America’s PVC/FKM Type-21a vented ball valve has a 1/8" factory-drilled on the upstream side of the valve to relieve potential for pressure buildup in the ball cavity. Now available is the option to add ½" flare end connectors, PFA flare nut and FKM seals; ideal for sodium hypochlorite applications.

Asahi/America

T: 800-343-3618

F: 800-787-6861

E: asahi@asahi-america.com

W: www.asahi-america.com

STORMWATER MANAGEMENT

The Platin tank features signature quality in a low-profile design for belowground rainwater harvesting. Minimizing the installation depth makes for faster installation and reduces excavation costs. Available with either the standard pedestrian loading lid or a cast iron vehicle loading lid. Its rugged design is paired with lightweight material to ensure easy handling and includes a 15-year warranty.

Barr Plastics

T: 800-665-4499

E: info@barrplastics.com

W: www.barrplastics.com

ULTRASONIC METER MEASURES CHEMICAL FEED

Accurately monitoring the amount of chemical being dosed to a system is crucial to ensure effective water and wastewater treatment. An overdose or underdose of chemical can adversely affect the quality of the treated water and leads to wasted chemical. SonicPro® MS6 Flow Meter uses transit time ultrasonic technology to provide immediate and easily accessible data on the amount of chemical being dispensed.

Blue-White Industries

T: 714-893-8529

F: 714-894-9492

E: info@blue-white.com

W: www.blue-white.com

DOUBLE CONTAINED PIPING SYSTEM

Duo-Pro® is an engineered double containment piping system made from polypropylene, PVDF, or ECTFE (Halar®). It is used for drainage applications, pressurized transfer lines, underground installations or installations that a lot of people will be in close proximity to. Chemical applications include sodium hypochlorite or bleach, sodium hydroxide, aqueous ammonia, sulfuric acid, or hydrofluoric acid. Leak detection options are also available.

Asahi/America

T: 800-343-3618

F: 800-787-6861

E: asahi@asahi-america.com

W: www.asahi-america.com

CHEMICAL METERING PUMPS NOW WITH 4-20MA FEATURE

Blue-White® now offers 4-20 mA signal out from their CHEM-FEED® MD1 Multi-Diaphragm Metering Pump and the FLEXFLO® M1 Peristaltic Metering Pump. The 4-20mA signal can be sent from the pump to a SCADA system where operators can remotely monitor the pump, allowing for improved automation and monitoring. The mA signal can be used as an input for another device to control multiple devices.

Blue-White Industries

T: 714-893-8529

F: 714-894-9492

E: info@blue-white.com

W: www.blue-white.com

ROTARY LOBE PUMP

The BLUEline Nova Rotary Lobe Pump sets new standards in pump technology and achieves unrivaled volumetric efficiencies. The newly developed DIUS rotors and the flow-optimized pump chamber ensure perfectly smooth operation at all pressure levels. Contact us today for more information! 612-4357300 or america@boerger.com

Boerger

T: 612-435-7300

E: america@boerger.com

W: www.boerger.com

BLOCK WATER FROM ACCESSING ASSETS

Road erosion, premature concrete failure or water ingress into wastewater systems? Denso’s 12" LT tape has been proven for nearly a century to block water from accessing assets. It won’t harden or crack and is the perfect solution to protect concrete and prevent I&I. Applied in minutes, requiring minimal surface preparation, no mixing or curing, it can be buried immediately.

Denso North America

T: 416-291-3435

E: sales@densona-ca.com

W: www.densona.com

CHEMICAL DAY TANK SCALE

The CHEM-SCALE™ from Force Flow allows operators to accurately monitor chemicals such as sodium hypochlorite, polymer and fluoride, when stored and fed from day tanks. Systems prevent over and underfeed conditions, and enable the documentation of amount fed. Available with Century™ hydraulic dial, advanced multi-channel Wizard 4000™, and other indicators.

Force Flow

T: 925-686-6700

E: info@forceflow.com

W: www.forceflowscales.com

FIGHT THE FOG CLOG

Operating lift station wet wells can be tough. “Flushable” wipes and fats, oils and grease (FOG) can cause ongoing problems. A GridBee© AP500 Air-Powered Wet Well Mixer will keep materials in suspension for easier grinder pump pass-through. Constant mixing also helps minimize grease layer formation, prolonging the time between vac and cleaning! See the results for yourself with a FREE TRIAL!

Greatario

T: 866-299-3009

E: info@greatario.com

W: www.greatario.com/greatwater

INSTRUMENTATION SUPPORT

Ensure dependable operation of your field devices with Smart Support by Endress+Hauser. Smart Support, the instrumentation support from Endress+Hauser, provides timely remote guidance on service operations, allowing you to increase your expertise, cut diagnostics, troubleshoot issues, save maintenance time and costs, and improve your process availability. Learn more about our customized service level agreements: https://eh.digital/43pSG5I

Endress+Hauser Canada

T: 800-668-3199

F: 905-681-9444

E: info.ca@endress.com

W: www.ca.endress.com

BOD SENSOR

The BOD EVO Sensor offers the most convenient way to get reliable results automatically on the analysis of BOD, also known as biochemical oxygen demand, for water and wastewater quality control. The sensor measures the progressive decrease of the internal pressure and it provides a direct measurement of the oxygen consumed by microorganisms in ppm (mg/l).

GENEQ inc.

T: 800-463-4363

E: info@geneq.com

W: www.geneq.com

CHLORINE EMERGENCY SHUTOFF

The Terminator™ Actuator from Halogen Valve Systems can be used on chlorine ton containers and 150-lb cylinders to instantly stop the flow of chlorine in case of an emergency. Shutoff is initiated when the controller receives a close contact signal from a leak detector or included emergency shutoff switch.

Halogen Valve Systems

T: 949-261-5030

W: www.halogenvalve.com

CATCH BASIN INSERT

The LittaTrap Catch Basin Insert is a low-cost, innovative technology that prevents plastic and trash from reaching our waterways. Designed to be easily retrofitted into new and existing stormwater drains, the LittaTrap is installed inside storm drains and when it rains, catches plastic and trash before it can reach our streams, rivers and oceans.

Imbrium Systems

T: 800-565-4801

E: info@imbriumsystems.com

W: www.imbriumsystems.com

CARTRIDGE-LESS SCREEN FILTERS

Orival Water Filters remove unwanted organic and inorganic suspended solids to protect nozzles, RO and ion exchange units, ozone and UV treatment systems or chlorination systems. With models from ¾" to 24" and filtration degrees from 5 to 3,000 microns, Orival Automatic Self-Cleaning Filters are designed to withstand the day-in and day-out rigours of POTWs and stay on-line during the rinse cycle, providing uninterrupted flow of clean water.

Orival

E: filters+ese@orival.com

W: www.orival.com

MAG-DRIVE PUMPS

Vanton Chem-Gard CGM-ANSI magnetically driven end suction pumps are sealless, single-stage process pumps which meet ANSI B73.1 specifications and conform to Hydraulic Institute Standards. All wet-end components are homogenous, injection-molded polypropylene (PP) and polyvinylidene fluoride (PVDF), eliminating metal-to-fluid contact, making them ideally suited for handling corrosive, hazardous and ultrapure fluids. Flows to 450 GPM, heads to 180 ft, and temperatures to 225°F.

Vanton Pump & Equipment Corporation

T: 908-688-4216

F: 908-686-9314

E: mkt@vanton.com

W: www.vanton.com

OGS/HYDRODYNAMIC SEPARATOR

The new Stormceptor® EF is an oil grit separator (OGS)/hydrodynamic separator that effectively targets sediment (TSS), free oils, gross pollutants and other pollutants that attach to particles, such as nutrients and metals. The Stormceptor EF has been verified through the ISO 14034 Environmental Management – Environmental Technology Verification (ETV).

Imbrium Systems

T: 800-565-4801

E: info@imbriumsystems.com

W: www.imbriumsystems.com

VERTICAL SUMP PUMP WITH RUN-DRY CAPABILITY

Vanton cantilevered vertical thermoplastic SGK pumps are engineered for the dependable handling of corrosive process fluids, plant effluents and wastewater, over broad pH ranges. Available in polypropylene, PVC, CPVC or PVDF, these rugged pumps are widely used across various manufacturing industries and water treatment facilities. Every Vanton pump is performance tested to the specified service condition intended.

Vanton Pump & Equipment Corporation

T: 908-688-4216

F: 908-686-9314

E: mkt@vanton.com

W: www.vanton.com

CONTROL CONTAMINATED GROUNDWATER OR SOIL GASES

Waterloo Barrier® is a containment wall for the control of contaminated groundwater or soil gases. Formed of steel sheet piling with interlocking joints that are sealed in-place in the ground, the Barrier offers a long service life, exceptionally low hydraulic conductivity, and documentable construction QA/QC. Installation is clean and rapid with minimal site disturbance.

Waterloo Barrier Inc.

T: 519-856-1352

E: info@waterloo-barrier.com

W: www.waterloo-barrier.com

Biological ion exchange shows promise to deliver safe water for island community

By William S. Chen, Jaycee Wright and Madjid Mohseni

Gillies Bay is one of two communities located on Texada Island, a 300-square kilometre island found off the Sunshine Coast along the southern shores of British Columbia.

While the several hundred visitors that come each year might know the island for its beautiful sunsets along rocky beaches, the 450 residents that call Gillies Bay home have not enjoyed stable access to clean, safe water for years. Several times each year, without fail, the community finds itself under a boil water advisory, requiring that residents boil their water before use due to the risk of harmful pathogens.

However, results from a 16-month pilot study conducted in collaboration between Gillies Bay Improvement District (GBID), which manages the water treatment and distribution infrastructure in Gillies Bay, RESEAU Centre for Mobilizing Innovation (RESEAU CMI), and researchers at the University of British Columbia, may finally point the path forward for the community to have clean and safe water.

NATURE OF THE CHALLENGE

Gillies Bay faces challenges shared by many small and hard-to-access communities, including a lack of funding. The limited revenue collected from its small user population is not sufficient to finance conventional treatment options like coagulation, sedimentation and filtration, which require large and expensive equipment.

Moreover, the town is separated from Vancouver, the nearest major city, by three ferry crossings, which delays servic-

ing and the delivery of parts and chemicals. A suitable water treatment solution therefore needs to be robust, reliable and cost-effective.

The primary treatment challenge for GBID is the removal of natural organic matter (NOM). Water is sourced from Cranby Lake, which sees an annual average dissolved organic carbon (DOC) concentration of 9 mg/l that reaches upwards of 18 mg/l during the summer. NOM in water, which forms from natural processes like plant decay, is not inherently harmful to human health. However, it interferes with disinfection processes and gives water an unpleasant taste and colour.

The current water treatment system at GBID is comprised of only a coarse screen at the inlet and disinfection using sodium hypochlorite (bleach) injection. Disinfectant contact time is provided by the transit time of the water through the distribution network.

When high water demand meets high DOC, as often happens during the summer months, the combined effects of decreased disinfection efficiency and decreased disinfectant contact time result in bacterial detection and the subsequent issuance of boil water advisories.

One of the key stages missing in the treatment train is thus the removal of NOM. However, with conventional meth-

A GBID water operator replacing the header on the 100-litre biological ion exchange filter vessel.

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ods being prohibitively expensive for the small community, a solution for removing NOM has remained elusive.

PROSPECTS OF BIOLOGICAL ION EXCHANGE

Ion exchange is a known method for NOM removal. It takes advantage of the negative charge of NOM at the near-neutral pH of raw surface water. Polymer beads (resins) embedded with positively charged active groups are used to bind to negatively charged NOM, thereby removing them from the water.

In the process, anions previously attached to these resins (typically chloride) are released. Once the resins are full of NOM, removal capacity can be restored by rinsing with a salt solution. This forces NOM to be released and chloride to be taken up once more. However, the waste brine produced by the regeneration process can be difficult to treat and dispose of, especially for remote communities.

Biological ion exchange (BIEX) is a new spin on ion exchange, coined through a collaborative effort by researchers at the University of British Columbia and Polytechnique Montréal. By simply reducing the frequency of regenerations and allowing native bacteria to populate the ion exchange resins, BIEX was found to sustain NOM removal for prolonged periods of time.

This method has been successfully piloted in Des Praires, Quebec, and implemented full-scale at the Dzit’lain’li community in Middle River, B.C. (Tz’latzen First Nation) to end a long-term boil water advisory.

Following the success of these past experiences, RESEAU CMI and GBID agreed to conduct a pilot study to assess the feasibility of BIEX filtration for the town of Gillies Bay.

PILOT STUDY AT GILLIES BAY

A pilot treatment system fabricated by BI Pure Water Inc. for RESEAU CMI was mobilized to Gillies Bay in May 2020. The system consisted of two parallel trains for biological ion exchange filtration, and granular filtration using activated carbon (coconut shell based), to compare the performance of these treatment methods.

Raw lake water was piped to the

pilot system from the existing network, where large particulates greater than 5-μm were removed through a series of bag and cartridge filters before being distributed to the 100-litre BIEX and activated carbon filtration vessels.

Filter effluent was discharged to the environment. Treatment capacity was

3 litres/min (26 min empty bed contact time [EBCT]) for activated carbon filtration and varied from 3.5 to 7 litres/min for BIEX filtration (10 to 20 min EBCT).

The pilot system was operated for 16 months from May 2020 to October 2021.

continued overleaf…

SUPERIOR DOC REMOVAL VERSUS ACTIVATED CARBON

Results of the pilot study confirmed the viability of BIEX for NOM treatment. Greater than 50% NOM removal was achieved using BIEX for 70 days of operation, whereas activated carbon only sustained this removal rate for less than one day.

A corresponding improvement in ultra-

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violet (UV) transmittance, an important parameter for UV disinfection systems, was also observed. UV transmittance increased to greater than 80% using BIEX for 70 days, whereas activated carbon filtration again only achieved this performance for less than a day.

Transition of activated carbon to a primarily biological mechanism of DOC removal (biological activated carbon [BAC]) occurred in less than two weeks and resulted in DOC removal averaging 10%. This remained unchanged until the end of the study.

As for BIEX, upon complete resin exhaustion, removal rates also decreased to 10% as biological removal became dominant. Again, this reduction in BIEX performance occurred more than 10 weeks after start-up, compared to less than two weeks for activated carbon/BAC.

Furthermore, two BIEX regenerations were performed over the course of the 16-month pilot study, each time resulting in successful restoration of NOM removal performance. These results confirm the long-term reusability of biological ion exchange media, which has important cost-saving implications for the community.

As part of ongoing efforts to further improve BIEX operation, the pilot study also involved experimenting with different protocols for backwashing. This included the flow of fluid in reverse through the filter vessel to flush out debris and restore

flow. Working together with the community’s water operator, UBC researchers discovered that injecting air (air scour) prior to a water flush was significantly more effective at removing suspended solids from the BIEX media. It improved NOM removal from 13%, up to 50%, averaged over four backwashing events.

These results are being further investigated using benchtop BIEX systems in the UBC laboratory, as researchers continue to optimize BIEX operation to make it viable for more communities.

WHAT THE FUTURE HOLDS

Following the pilot study, GBID is pursuing the design and construction of a full-scale water treatment facility that will utilize BIEX. The utility operator has been long expectant of a new treatment system, but needed to ensure that whatever technology they invested in would be effective long term.

The promising results of the pilot study suggest that biological ion exchange may finally offer the solution needed to provide clean and safe water to the residents of Gillies Bay.

William S. Chen, Jaycee Wright and Madjid Mohseni are with the University of British Columbia Chemical and Biological Engineering. For more information, email: wschen@mail. ubc.ca, jaycee.wright@outlook.com, madjid.mohseni@ubc.ca

GBID pilot treatment system comparing DOC removal with BIEX and activated carbon/BAC filtration. Fluctuating DOC removal of BIEX (300-400 days of operation) reflect the effect of air scour backwashing that temporarily increased DOC removal rates.

Battery-powered

Multi-Point Insertion Magnetic Flowmeter

Introducing TORPEE-MAG – the groundbreaking new battery powered multi-point insertion magnetic flowmeter from Flow-Tronic. This evolutionary waterproof self-contained insertion flowmeter is powered with batteries for on-site power offering near real-time profiling for virtually any flow monitoring application!

Graphite electrodes

Long term stability

Improved sensitivity at low velocities

Guaranteed calibration stability for a minimum of 5 years

No on-site calibration required

Multiple electrodes across the flow section

No installation error possible

Near real-time profiling

A fully developed profile is not required

Applications

District Metered Areas

NRW, water balance and night flow analysis

Any flow monitoring application without mains power available

• 100% removal of floatables and neutrally buoyant material debris 4.7mm or larger.

• Self-cleaning screen reduces maintenance costs.

• Internal bypass eliminates the cost associated with additional bypass structures.

• Multiple pipe inlets and 90-180º angles provides design flexibility.