Water Journal December 1982 by australianwater

ISSN 0310- 0367

Official Journal of the

, Et•k-i i;f!1 ! M: l!Wi =I ;f~: I•) '1%~i i=Wffi i=I ;W-$i•XeJ f!lit•)~ 1

I Registered by Australia Post - publication no. VBP 1394

Vol. 9, No. 4, Dec. 1982-$2.00

More sizes. More options. Amillion ways to specify the DeZURIK eccentric valve. 28 sizes , Â˝"-72". 15 body materials . 5 end styles . 5 packing materials . 9 resilient plug facings . 5 actuators and 29 accessory options . Over a million combinations, and DeZURIK controls the quality every step of the way. The DeZURIK foundry and rubber molding operations assure material quality and valve performance. Actuators are designed and built to valve requirements. Versatility. Quality control. Proven per1ormance. That's why DeZURIK eccentrics are specified for the toughest municipal applications. Eccentric action and resilient plug facings-for a lasting, dead-tight shutoff .

Rugged, machined bearingsprevent binding and assure lasting , easy operation without lubrication. Corrosion resistant nickel seatminimizes plug wear on all 3"-72" cast iron valves . Multiple ring stem seal-seldom , if ever, requires adjustment or

replacement, even under continuous operation . For more information contact : DeZURIK OF AUSTRALIA PTY. LTD. P.O. Box 204, Vineyard Road Sunbury, Victoria 3429, Australia, Telephone : 03-744-2244 Telex: AA33732

__;~ ...,._-- TOTALLY ENCLOSED POWERED OR MANUAL ACTUATORS

--WELDED-IN NICKEL SEAT

CORROSION RESISTANT BEARINGS A UNIT OF GENERAL SIGNAL

DeZURiiK

FEDERAL PRESIDENT F. Bishop, Scott & Furphy, 390 St. Kilda Rd., Albert Park , 3004

FEDERAL SECRETARY F. J . Carter, Box A232 P.O . Sydney South, 2001.

FEDERAL TREASURER J. H. Greer, Cl- M.M.B.W. 625 Lt. Co llins St., Melbourne, 3000.

BRANCH SECRETARIES Canberra, A.C.T. J . E. Dymke, 4 Story St., . Curtin, 2605. Office 062 (81 9385)

New South Wales D. Russe ll , Camp Scott & Furphy, 781 Pacific Highway, Chatswood 2067. (02-412-2688)

Victoria J. Park, S.R .W.S.C. Operator Training Centre, P.O. Box 409, Werribee, 3030. (741-5844)

Queensland K. Strick land , C. I.G. Ltd ., P.O. Box 40, Rock lea 4106.( 07 275 0111)

South Australia A. Glatz, State Water Laboratories, E. & W.S. Private Mail Bag, Salisbury, 5108. (258-1066)

Western Australia R. Loo, 455 Beach Rd ., Carine, 6020. (09-447-6550)

Tasmania G. Nolan , 21 Browne St. , W . Hobart, 7000. (002-28-0234)

Northern Territory M. Wyatt, P.O. Box 37283 Winnellie, N.T. 5789.

Official Journal of the AUSTRALIAN WATER AND WASTE WATER ASSOCIATION

Vol. 9, No. 4 December 1982

CONTENTS Viewpoint . .... . ....................... . ......... ii<•••

Association News, Views and Comment ................ .

IA WPRC News . . . .............. . .......... .. ..... ... .

Recent Overseas Developments in Biological Surveillance -J. F. Skidmore .................. . ... . . .. ...... .

Technical Interests . . ............. .. ... . ... .. ...... . . .

Your Federal Convention-April 11·15th International Content ........ .. ... . ... .. . . ....... .

Extended Aeration Treatment of Saline Waste waters -L. Applegren ......... . . . .... .. .. .. ..... . ... .. .

Calendar ......... . ....... . .......... . .. . ... .. . . .... .

Perth Upgrades Treatment Plants ........... . .......... .

Water Filtration Using Locally Available Sand -Olusola Ogedengbe . ...... .. ........... . . . .... .

Book Review, Company Announcement ........ , ....... .

Plant and Equipment .. . ..... . . ... .. . .............. . . .

COVER Water at (ow level in Maroondah Reservoir, one of the eight storage reservoirs which provide Melbourne 's water supply, which is administered by the Board of Works. The prolonged drought, which has resulted in the lowest winter and spring rainfalls on record, has been a cause of concern for several months and has necessitated the introduction of restrictions on the use of water in Melbourne from December 1. The whole of Australia is now feeling the impact of a near record drought. 'Vanishing water supplies, devastation to the man on the land, dying stock, financial disaster to country centres and advancing effect upon our cities. The lesson is old, not new. We have a thirsty land; conservation, economy in use, and re-use must be our watchwords.

Th e statements made or opinions expressed in 'Water' do not necessarily reflect the views of the Australian Water and Wa stewater Association, its Council or committees.

WATER December, 1982 I

AUSTGEN-BIOJET INTERNATIONAL PTV. LIMITED Th is company is seeking to appoint a Manager for its Victorian State Office. The successfu l Appointee will be a graduate eng ineer with a marketed oriented approach . Total responsibi lity for State Operations w ill res ide with this position. The company's major area of activity is in Waste Water Treatment whi lst a significant involvem ent in other areas of B iotechnology over the last two years has been founded. We want a Top Man and we w ill pay Top money for the rig h t person. The company has offices in Queens land, N.S.W., U.S.A. and .Japan at present. App li cants in the first instance shou ld send a brief resume marked Private and Confidenta l to Mr. S . .Jones, Manag ing Director, P .O. Box 626, Chatswood N.S.W. 2067 Australia.

ENVIROSHIELD Âˇ~ Laboratory (Queensland) For Independent Analysis of Water and Wastewater

For further information: C.I.G. Enviroshield, 1688 Ipswich Road, Rocklea, Brisbane 4106 Phone: (07) 275 0196 Telex: CIGAS AA40498 2 WATER December, 1982

Technolo ical advances in water an • waste management t t xt Up tO th e mInU e e S from Butterworths Tools '11 use every day 0 U Y I

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POLLUTANTS IN NATURAL WATERS Atmospheric Pollutants In Natural Waters

Ed. SJ Eisenreich Un iv. of Minneapolis. Topical work looks at occurence, Ahnoo,prn'rK PollulJnh transport and anthropogenic organics In N.atur,11 W.tlt-r~ to natural (primarily fresh) waters. Examines wet, dry and gaseous deposition, prior to covering accumulatory mechanisms at air/ water interfaces. .-;:::.::......-....,;.::.,...i:~ Subsequently discusses nutrients , toxic metals and anthropogenic organics to freshwater lakes. No. 70639 . . $52.00 Adsorbtfon of lnorganlcs at Solfd · Liquld Interfaces . MA Adderson and AJ Rubin

1981. Compares the behavior of inorganic ion adsorbtion at the solid liquid interface. Readily applicable to lake systems . Soils chemists will benefit from up to date presentation of nutrient adsorbt ion. No. 65878. . ......... . .... $56.00 - - - - - - - ~ Chemistry of Natural Waters SD Faust & OM Aly.

u------..i 0l[MISTRY OF NATURAL WATLRS

New(1981)work examines the natural chemical factors affecting water quality. Provides essential chemical bases Provides essential chemical bases that control dissolved constituents in natural waters, An invaluable text in assessing water problems No. 63264 .. ... .. $52 .00

Water Chlorination : Environmental Impact and Hea lth Effects

source of practical research in this rapidly changing field. Includes a 10 year comprehen sive index (both subject and author) of current and previous volumes. No. 70611 ... $95.00

New Concepts and Practices In Activated S ludge Process Control. RA Arthur

INDUSTRIAL WASTE Purdue 35th Industrial Waste Conference Proceedings

JM Bell(Ed.) Purdue Univ. (1981) The most complete coverage of solu tions to industrial waste problems in any single volume . The Proceedings give you case histories with operating data on every facet of the subject. Invaluable for anyone involved in waste treatment. The most comprehensive and advanced

..............

------"""" ftCHHO\.OGY

Decomposition of Toxic and No~Toxlc Organic Compounds In Solis

MR Overcash and D Pal North Carolina State Univ. 1981 . Innovative new book offers latest information on toxic , hazardous and non-toxic orga nic compounds. Information vital for land treatment of industrial wastes. ... $94.00 No. 73315 . Water Reuse . E Joe

Middlebrooks (Ed). Full analysis of engineering , legal , social , administrative, monitoring and marketing considerations. Has design data , case histories , health and monitoring information , social implications and legalities. No.7351 0 . .... . $54.00

RL Jolley, WA Brungs , RB Cumming . Vol 3 (Just publi shed) . This important new book presents the current state of knowledge, with emphasis on chlorinated organic compounds and associated biomedical and environmental effects. Problem areas , research needs and alternatives to chlorination are discussed. No. 37613 ... $4 7.50

ii~Err~~i~ :;~;~ent. ~:~~aast~r~~dterrestial ecosystems as related ~f:~f:~ i:~r~l~~~ent. hydrocarbons on p lants and animals , ammon ia on aquatic organisms and pipeline constructions on stream ecosystems. No. 103621 ... ·$54.00 Treatment & Disposa l of Wastewater Slu dges

1982. New control strategies includ ing a new concept of food to microorganism ratio and a new method to control return sludge. Includes anticipatory control of aeration. No.103514 .. .... $40.00

Land and Water

2nd Ed. P. Aarne Vesilind 1979,80 . Covers the analysis and design of sl udge treatment and disposal systems. Concentrates on the systematic organisation of sludge processing operations. Several new chapters and improvements are included in the second edition. No. 67509 . . . $43.50

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~ 'I

Dictionary of Waste and Water Treatment

JS Scott & PG Smith 1981. The most comprehensive dictionary on the subjecl yet available. Over 6000 terms defined , with both US and UK terms and process design data where relevant. An essential reference for engineers and students working in all aspects of ... $56.00 environment con trol. No. 24958

Butterworths WAllll REUSE

2 71 -2 73 Lane Cove Road , N ort h Ryde 2 11 3. Phon e (02) 887 34 44 ' All books are available on 14 days trial. If you are not completely satisfied with any ol the books purchased , simply return them with in 14 days for a lull refund. Please supply the following books :

:--- a,...... ·,::,!'..·•\t··"·

~--

_-:-::.;. - ·

D D D D D D D D D D D D

No. 70639 . . ... $52 .00 No. 65878 . . . . ... . $56 .00 No. 63264 . . ..... .. $52.00 No. 37613 . .. ...... .. .... . .. ... $47.50 No. 706 11 . . . . . . .. . . . .. . . . .... $95.00 ... ... $40.00 No. 103514 No. 73315. . .. . .... $94 .00 No. 7351 0 . . ... $54.00 No. 66706 . . .. . . . .. .. . . $39.00 No. 103621 .. $54 .00 No. 67509 . . .... $43 .50 No. 24958 . . .......... . ..... . ........... $56 .00

D Cheque/ Money order enclosed Please debit my credit account as follows: D Bankcard D Diners Club D American Express Card No:

~ I I I - - - -- - -- - - - - - - - - - - - ---ii Expiry date: /

WASTE WATER

! Signature

-ln_d_lv_l_d_u-al- 0- ns_lt_e_ W_a_s_te_w_a_t_e_r _Sy _s _t_e_m_s_ _ _ _ _ _~ Name·

NI McClelland (Ed) 1980 Sixth Annual Conference. Covers applications of alternative technologies being used to resolve onsite wastewater problems .Covers problems being solved , identify criteria and describe effective management programs . No. 66706 . . . $39 .00

I Address .. I Postcode . I Recommended Domes tic Retail Prices include postage and are subject to change wi thout notice. This order is subject to I acceptance by the Head Office of Butterworths.

---------------WATER December, 1982 3

TORRENS INDUSTRIES Tl 1003

~~EUWA

GENERAL ALARM MONITOR AND PAGING SYSTEM

WATER TREATMENT p

FIELD PROVEN The Tl 1003 ,s a fleld·proven alarm

momtormg and alerting system which amongst othe r appl1cat1ons 1s particularly suited for mon1tonng waste water pump s1at1ons MICROPROCESSOR BASED

The system ,s microprocessor based and will report and log alarms lrom up to 64 pump sta11ons with 8 mpuls each UHF RADIO PAGER Unattended alerting 1s via self -contamed

UHF Radio Tran smitter and pocket pagers which have a lypical range ol 30 kilometres SYNTHESISED VOICE

When an alarm occurs and the sys tem 1s 1n the " remote " mode . lhe microprocessor .. speaks .. the synthesised s1a11on and alarm 1nlorma11on via the pockel pager units and also by phone . when the operator acknowledges recei pt ol !he alarm FUTURE EXPANSION An important featu re of the system allows unskill ed

personnel

add

luture

stations by plugging a c1rcu1t card mto the base and adding a Transponder ,n the remote station The m1croprocessor ,s pre-programmed to accept up to 64 stations No adJustments are reqwred DATA GATHERING PANEL

Allows unskilled operalors to expand syslem lrom 1 10 64 pump s1a11ons by plug-in cards and adding remote Transponders Fron! panel LED 's display all alarm points . the system 1s lully Telecom approved (No C79·26·41 ) MICROPROCESSOR MODULE Incorporates prin1er . date and time display , voice synthesiser . phone acknowledge c1 rcu11. audible alarm sounder and accept key All s1a11on and alarm mlorma11on 1s prtnled together with date and 11me . PAGER MODULE

Includes pager encoder and UHF rad io tran smi tter Front panel keyboard allows manual page lac1h1y for contacting personnel within a typical 30 km radius CHARGER AND BATTERY MODULE

Separate vented enclosure includes ·· no maintenance·· battery which ensures 24 hour continued operation in the event of power ta,lure No power 1s required in the fleld . as all Transponders receive their power lrom the base ol Telecom ltnes Torrens Industr ies manufactures a lull range of equipment including

7000 ser,es V.F Remote control and md1ca11ons equipment Tl 1000 Fire Reporling Systems and Tl 1010 Portable Evacuation Alarm Unlls

For more information on the Tl 1003 or other product lines, conta ct: Field Transponders

IITarren~col~te~~ieV.}f.!5 P1y l1d Orb House, 95 Wollongong Street , Fyshwick A.C .T. 2609. Telex: 62044 P.O. Box 41, Torrens, A.C .T. 2607 , Australia Telephone : (062) 80 6609, 80 6897 4 WATER December, 1982

EUWA-INFO-COUPON Please inform me in detail of the following systems. (Place cross against information requested and post today.)

1o 2o 3o 4o So

EUGEMAT. Countercurrent regenerating ion exchange ELECTROQIARESE Electrically regenerating ion exchange ELDEC "A". Electrical Ionization measurement of carbonates in water Differential conductivity control of cation ion exchange Degaslfying and Thermal DegasifyinQ , Deacidlflcation and Oxidation

SterllizinQ and Disinfecting

EUDOMAT system for removal of Nitrates

Water treatment for Breweries, and Soft Drink plants

EUWA (AUST.) PTY. LTD. Water lreatment Plants 196 Magill Road NORWOOD SA 5067 Tel. (08)3321133 Telex 87286

:~EUWA

EDITORIAL Chairman , E. A. Swinton F. R. Bishop B . P. Maguire · Dr.Wayne Drew W . Rees B. Robbins J . H. Greer R. McGrath J . E. Dymke D. Hammerton G. Nolan R. Vass G. Jackson Dr Barb. Bowles D. Simpson Ed itor: Publisher: G. R. Goffin A .W.W.A . BRANCH CORRESPONDENTS CANBERRA A.C.T. J . E. Dymke 4 Story St. , Curtin 2605 Office 062-54-1222

NEW SOUTH WALES W. H . Rees Inv. Eng ., Advance Planning M.W.S.&D.Bd . P.O. Box A53 Sydney South 2001 02-269-6595 VICTORIA R. Vass, M.M.B.W. , P.O. Bo x 4342, Melbourne 3001. 03-615-4362 vUEENSLAND D. A . Simpson Munro, Johnson & Ass. P/L P.O. Box 57 Spring Hill 4000 07-221-6616

VIEWPOINT TRAINING AND EDUCATION FOR THE WATER INDUSTRY Ed ucation a nd tra ining is a vita l in te rest a nd co ncern of the Associatio n a nd the Wa ter In d ustry. One o f the Associa tion obj ectives is th e di sseminatio n o f the ad va n~ s in enginee rin g sc ience and public health in th e water industry. This can be achieved by publi catio n of tec hn ological in fo rm a ti o n a nd by the spo nso ring of conve ntio ns, sym posia, worksho ps a nd meetings. O ur J o urn a l Water meets in part this need a nd in 1983, the third yea r in th e UN Wa ter a nd Sanitati o n Decade, the Associati o n will be ac tive in runnin g two major scientific co nfere nces. Firstl y th e 10th Federal Convent ion in Sydn ey fr om I Ith -15th April , 1983 with a du al stream th eme of clean o r pota ble water a nd wastewater. P a pers will be presented by engi neers and scient ists fr o m A ustrali a, E uro pe, Uni ted Kin gdo m , No rth Ameri ca, Midd le East, Asia, New Zeala nd a nd South Africa. T his conventio n will be foll owed by a specialist co nference in Da rwin fr om 4th to 9th September, I 983 on the th eme " Water Regime in relation to Mining, Milli ng a nd Was te Treatment including Reha bilita tion with emphas is on Ura nium Mining", with pa rti cipa tion by overseas specia lists. T hese conventi ons will pro vide a n in tercha nge of skills a nd kn owledge on ma ny fa cets o f the water industry, no t o nl y in Australia bu t in ma ny ot her pa rts o f th e wo rld , which may lead ultima tely to better solutio ns fro m socio-econ o mic, tec hnological , environmental a nd resource manage ment view po ints.

SOUTH AUSTRALIA B. P. Maguire I. & T. Branch E. & W . S. Dept. Victoria Sq . Adelaide 5000 . 08-227-3966

The second obj ecti ve stems fro m the need for flexibility to meet the cha ngin g needs of the eighties, namely progressive think ing a nd educa tion not o nl y of technologists in th e water industry but o f the pu blic at la rge a nd o ur, governments who need to be kept in fo rm ed o f iss ues and solutio ns in the cha nging wo rld of the wa ter industry.

W ESTERN AUSTRALIA B. Robb in s , Camp Scott & Furphy 47 Ord St. , W. Perth 6005 09-321 -4582

The Association in the past , like most lea rn ed societi es, has kept a lo w profile on public sta tements. Federal Co un cil resolved a t th e November l::o un cil Meeting th a t the Associa tion sho uld speak res po nsibl y o n matters of publi c con cern - a lbeit such sta tements will be fact ual, logical and based on so und scientific principles. I commend this approach to Members as benefi cial to the Natio n a nd th e general public.

TASMANIA G. Nolan , 21 Browne St. , W . Hobart , 7000 . 002-28-0234 NORTHERN TERR ITORY G. Jackson, P.O. Box 37283 Winnellie 5789 , 089-84-4063 . EDITORIAL & SUBSCRIPTION CORRESPONDENCE G. R. Goffin, 7 Mossman Dr., Eag lemont 3084 , 03-459-4346 ADVERTISING Miss Ann Sykes , Appita, 191 Royal Pde. , Parkvi I le 3052 . 03-347-2377

FRANK R . BI SHOP Federa l President

AWWA MEMBERSHIP Requests for Application Forms for Membership of the Association shou ld be addressed to the appropriate Branch Secretary. Membership is in four categories: • Member - qualification s suitab le for membership of the In stitution of Engineers (Aust.) or equiva lent qualifications of similar profe ssional organisations . Fees $20 p.a. • Associate-E xperience in the water and/or wastewat er industry without formal qua lifications . Fees $20 p.a. • Student. Fees $5 p.a. • Sustai nin g Member-an organisation or firm invo lved in the water and wastewater indu stry , w ishin g to support and further the aims of the Asso ciation. Fees $100 p.a. W ATER December, 1982 5

ASSOC/A TION NEWS VIEWS AND COMMENTS PRESIDENT'S MESSAGE The November meetin g of the Federal Council on the 5th followed a meeting of the Executive Committee on the preceding day. Some of the key issues discussed were:

FRANK BISHOP FEDERAL PRESIDENT At the November meeting of the Federal

Council, Doug Lane stepped down after two meritorious yea rs as Federal President and is succeeded by Frank Bishop from Melbourne.

Rev iew of Standing Committees: President Doug Lane tabled a report reviewing the role, sit uation and future of the various Standing Committees which are State based but enab le Federal Council to react prompt ly to key issues.

ERRATA

21st Annua l Report The final draft is being rev iewed and edited prior to printing.

Conferences Detailed arrangements by the N .S. W. Organizing Committee are well advanced for the 1983 Sydney Convention. Active promotion of the Convention by all States is essential. Some 43 of the 85 papers in the technical programme have been received and are being reviewed. Planning for the Northern Territory Conference later in 1983 is well under way under the Chairmanship of John Paul. Elections The Federal Counci l elections were he ld at the November Meeting with the incoming President a nd Vice President being Frank Bishop (Victoria) and Bob Lloyd (N.T.) respectively, and Secretary John Carter, Treasurer Jim Greer, and Assistant Secretary Rex Dengate continuing their good work . Doug Lane steps down as Federal President after two years in office, and the thanks of Federal Counci l and the Association are extended to him for his efforts and initiatives to promote and develop the Association .

FRANK BISHOP Federal President 6 WATER December, 1982

PLEBISCITE Th e recent ples biscite on amendment to th e rules of the Association yielded the following resu lts: Voting papers issued to Members 1470 47 1 Replies for adoption Replies against adoption 4 Inform al 2 The '1982 Rules' now become the ' Rules' of the Association Members are asked to make the following corrections to the newly issued 1982 Rules. Page 2, Clause 3(2) to read' Recognise, declare ... ' Page 12, Clause l4(a), 3rd line to read'advantage of . . .' Page 12, Clause l 5(a) to read, A plebiscite of ... ' Page 14, Clause I 7(b) to read 'The Annual Meeting of ... ' Page 15, first line to read' ... payments of the debts and ... ' Page 15, Clause 22(c), last line to read'Meeting of the Council'.

Plebiscite on Rules of A WWA (1982) The plebiscite found. 471 members in favour, four against a nd two informal, thus the revised Rules now become the Ru les of the Association.

Public Statements The vital interest of Councillors in matters of public concern in the water industry evoked co nsiderab le di sc ussion an d resulted in a decision that the Federal President be encouraged to speak out on matters of public concern to the Association and that State Branches should also be encouraged to take th e initiative in making statements providing the subject matter be first referred to the Federal President who has authority to act on behalf of the Association in these areas.

ASSOCIATION RULES

NORTHERN TERRITORY BRANCH ACTIVITIES

Frank is currently Chairman and Managing Director , Scott & Furphy Consulting Group, having commenced with that firm in 1949 after previous experience with a civ il contractor and with the Australian Army 1942-46. He has had most extensive experience with many water resource, hydrology, water treatment, sanitary engineering and environmental engineering projects in Australia, Papua New Guinea, Indonesia, Malaysia and Vietnam, and has developed expertise widely recognised in these fields. In the Association he has served as Victorian Branch President, and Comm ittee Member for many years. He is a foundation member of the Journal Committee and one-time Chairman, and has been a Federal Councillor si nce 1977. Frank is Past Chairman, Civil Branch, Institution of Engineers, Australia, and Past Chairman, Victorian Local Association, Insti tution of Civil Engineers, London. He holds the Fellowship Diploma, R.M.I.T. and Master of Engineering from the same Institute, and is Member, Groundwater Appeal Board (Victoria) and Lecturer, Melbourne University - Appropriate Technology for Water Supply and Sewerage. The Council and Members congratulate Frank on his election and the Association looks forward to a profitable period of growth and advancement under his Presidency.

Committee and Office Bearers for 1982/ 83 are: President, John Paul; Vice-President, Ron Freyling;, Hon . Sectretary, Michael Wyatt; Hon. Treasurer, Ron Frey ling; Committee - Peter Ball, Graham Jackson, John Kenworthy, Con Mappas, Percy Wijenayake. On 28 October some 30 members attended a talk on the Reuse of Sewage Effluent at North lakes Estate presented by Rod Jackson and Norm Allen from the Department of Transport and Works, Water Division. The proj ect involves the pumping of treated sewage from the Leanyer Sewage Ponds to the Northlakes Estate - a residentia l development associated with the Darwin Golf Club. The effluent is chlorinated on leaving the ponds and rech lorinated on being pumped from the ho lding ponds at the golf course, before being used to water the freeways and greens. The 5 km delivery pipeline has several take-off points for future use by the Darwin City Council. The effluent quality is being monitored by the Water Division Laboratories for the framing of a management programme in conjunction with the Department of Health. Coming Events

As we go to press the programme has reached us for the balance of this year and

ASSOC/A TION

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well int o 1983 and it reflects an energetic approach by the innovators meriting solid support by members. December 16th-Film evening plus wine and cheese. January 27th-Polluti on of N.T. Underground Water Sources, Graeme Porte. February 24th-Occupational Health, John Erkins. March 24th-Ciquatera in N.T. Fish-Effects of Temperature, Pollution on N.T. Fishing industry-Pearling Industry-Green Prawn Industry, Koolpinya by Dr. J. Quinn and Max Chambers. Apri l 28th-P lanning Darwin's Next Water Source, Rod Jackson. May 26th-Water Filtration Plant, Katherine . June 30th-Clean-up of Rum Jungle, John Paul. . Jul y 21st-Problems in Operating a Municipal Dump, Duncan Beggs . To be advised-Trade Wastes and Their Disposal Act, Percy Wijenayake. September 4-9th- Darwin Specialist Conference. September 22nd-A.G.M. STATE NEWS

A water treatment plant installed by William Boby & Co. has recently been commissioned at Katherine. The plant treats water from Donkey Camp on the Katherine River with an upflow clarifier using alum and soda ash for pH adjustment , followed by rapid sand filters. This water source replaces ground water from the Tindal Limestone aquifer which has been the main so urce for the last 12 years. The first stage (22 km) of the duplication of the pipeline from Darwin River Dam to McMinns Pumping Station with a 1400 mm nominal size M.S.C.L. pipe is well advanced . When completed in 1983/ 84 the pipelines are expected to have sufficient capacity for the needs of Darwin well into the 1990s.

QUEENSLAND BRANCH ACTIVITIES

The program for 1983 is being prepared and will include a Regional Conference. The first Regional Conference held at Broadbeach on the Gold Coast in 1975 was attended by some 40 delegates a nd was a great success. It is hoped that the 1983 Regional Conference will be even more popular. More news of the I 983 program and Regional Con Ference in later issues. At the General Meeting on October 27th, Vince Schmidt spoke on 'Experiences in Papua New Guinea in Organising Water and Wastewater Treatment'. The talk made

members aware of the significant differences encountered in moving away from the usual local urban scene and encountering the problems of developing communities. On November 24th Leon Henry's talk was most topical in this dry period - 'Water Resources of Australia - Usage and Ways of ConservinJ? Supplies'. He emphasized that

NEWS

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VIEWS

while the householder is usually the target of appeals for water saving measures, even in cluding the time honoured 'brick in the cistern' there are other avenues of savings offering better returns and less hardship to hou seholders. Extension of available resources by reclamation and recycling featured amongst the measures discussed. The Queensland Branch finances are in a healthy position and the Committee will be looking at increasing the services to members in vario us ways. The survey of Members' Preferences on the Format of General Meetings closed on 30 November 1982. Results should be known in the near future. Several changes have occurred in the Branch Committee. Robin Black has resigned as a Comm itteeman. Ian Bell has resigned as Secretary a nd this positon will now be held by David Pettigrew. Norm Whyte has resigned as Treasurer and Julie Ivison has been seconded to the Committee to fill this position. Both Ian and Norm will remain on the Committee. Many thanks to Robin, Ian and Norm and in particular to Norm who has been a most capable Treasurer for the last two years. Su bseq uent to our September comment the Town Water Supply and Sewerage Branch of the Department of Local Government is now undergoing a long-awaited reorganisation. The reorganisation was proposed years ago and includes the formation of a Research and Development Section, and it follows the retirement in August last of the Chief Engineer Jim Turnbull. The Queensland Branch Newsletter is alive and well and is a valuable form of communication with the members. The November issue was accompanied by some most interesting notes on the 'Effects of Tidal Barrages on Estuarine Water Quality' (M. Miller) with comment on existing barrages and studies of various proposals a nd 'cases' . Also with the November issue was an article by Mr. John Wheeler on the 'New Queensland Marine Parks Act' and its relationship with the Commonwealth 'Great Barrier Reef Marine Park Act' . All with considerable detail of the impact and value in implementing environmental protection. Other and most informative notes ranged from topical references to water quality criteria, the new National Water Research Council, cheaper pumping to ozone sterilization of sea water for oyster farmirig.

WESTERN AUSTRALIA BRANCH ACTIVITIES

The old order changeth and after a lengthy and well appreciated stint as Correspondent Charles Tucack has handed the communication reins to Barry Robbins who takes up the burden with this issue. Editor. Hi there! Members of A WW A, this is Barry Robbins

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COMMEN~

- who volunteered for the position of WA Branch Correspondent during the utter si lence at our last committee meeting when the job was declared vacant. Other committee members were studyi ng their shoes, or a tree outside the window, or anything other than the face of Chairman Noel Plate! who had just requested a nomination for the job . The minutes record that I was nominated, seconded and elected unanimously . In order to make this column as diverse as possible, would any WA members who have newsworthy or humorous items kindly phone me on 321 5036 so that I can spread it around the country in subseq uent issues of "Water". Comir..it Events

As we go to press, on November 24th, the Branch will hold its Annual Social at 'The Waterfront'. A complete and frank account of the festivities should lighten the next issue of Branch News. Meetings planned for the new year are: February 9th, 5.30 p.m. - at Institution of Engineers Headquarters, Dr. B. Kavanagh, Chief Chemist of the Metropolitan Water Authority and Dr. E. Wajon of W.A. Institute of Technology, will present a paper entitled 'Odours and Tastes in Drinking Water'. Dr. Kavanagh will review factors considered responsible for tastes and odours in our Metropolitan drinking water - and the treatment processes available for their removal. Dr. Wajon will outline a program of investigation being undertaken to isolate the causitive agents associated with tastes and odours in potable water supplies. During March 1983 (date and venue to be advised) Mr. J. Abbott of Public Works Department, Mr. J . Hall of Geological Survey of W.A. and Dr. G. Ho of Murdoch University, will give a paper on 'Recent Developments in the Disposal, Neutralization Mechanism and Monitoring of Laporte Effluent at the Leschenault Peninsula'. The

paper will deal with the history and problems associated with disposal of the Laporte effluent, the hydrology of the disposal area and processes, and the chemistry of neutralization and immobilization of iron in the dune system in which the effluent is discharged. Hong Kong Tour 1983: There are thoughts of an Eastern tour September 10th-23rd to follow the 1983 Darwin Conference. Provisional cost for the round trip from Perth is $1250. For details see Waisted Warters of October 30th or contact our indefatigable secretary Rein Loo. STATE NEWS

The

University

of Western

Australia

(U.W.A.) recently named its new research

vessel the Djinnang II, the vessel will be used primarily for research work in environmental dynamics by the Centre for Environmental Fluid Mechanics at U.W.A. - which is under the direction of Professor Jorg Imberger. For three years, members of the Centre have worked on the design of a replacement WATER

December, 1982

ASSOC/A TION for the Djinnang I, which served as a development model for a new concept in lake and ocean monitoring on location. Much of the equipment for Djinnang II had. to be designed, developed and constructed at U. W ,A. The boat was constructed locally by Court Marine. The hardware costs are approximately $350,000 and the development costs of both the hardware and software involved some six to eight man-years effort. The Djinnang II is equipped with three separate computer systems which are interlinked and which allow complete data transferability. The first computer is a data acquisition system, the second is a dedicated processor for image enhancing the echo sounding signals and the third serves as the numerical simulation system. In addition a series of new instruments has been developed to measure the salinity, temperature, velocity and water quality fields . Salutation

On behalf of our President and Committee may I wish all state and federal members and their families a Merry Christmas and a prosperous New Year. The best way to guarantee the latter is to burn your wife's bankcard!

TASMANIA BRANCH ACTIVITIES

Committee and Office Bearers for 1982/83 are: President: Mr. D. Walters Vice President: Mr. P. Spratt Immediate Past President: Mr. H . McFie Secretary: Mr. G . Nolan Treasurer: Mr. A. Young Committee: Messrs. B. Healey, J. Lawrence, McEwan and J. Stephens Federal Councillors: Mr. D. Walters and Mr. H. McFie At the meeting on the 6th September, Alan Robson, Executive Director of the Water ' Research Foundation of Australia gave a talk on the aims and background .of the Foundation. Membc;rs and guests who were present at the talk appreciated the opportunity to be brought up to date with the status of current research projects being funded by the Foundation. The Branch's Annual General Meeting, held on the 30th September was attended by 30 members and wives. The venue was the Customs House Hotel and the meeting was addressed by the Federal President of the Association Mr. D. Lane. Members enjoyed the opportunity to hear first hand details of the Association's activities at a Federal level. Branch President Mr. H. McFie presented the annual report and also expressed appreciation to the outgoing Branch Secretary Mr. P. Spratt who had filled the position for the past eight years,

8 WATER December, 1982

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VIEWS

On the 5th November Mr. F. Burns talked to the Branch on the Artificial Destratification of Reservoirs. Mr. Burns has had some 30 years experience with the State Rivers and Water Supply Commission at Victoria and has specialised in water quality for the last decade of this period . He has been consulting for the last 18 months. Mr . Burns spoke on the principles and effects of stratification and the methods of artificial stratification and described in detail the application of these to Tarrago, Eppalock, Little Bass and Eildon Reservoirs. The final event for the year will be the Branch Christmas Dinner on November 24th as we go to press.

NEW SOUTH WALES BRANCH ACTIVITIES

In a most interesting talk on August 12th, Mr Richard Connolly, Director and Chairman of the Metropolitan Waste Disposal Authority explained how the Authority handled the problems offered by 6000 tonnes daily of solid waste and the annual complement of two million motor tyres and 70 million litres of liquid waste. The Authority has established planning objectives extending beyond the turn of the century and has · rationalised collection and disposal throughout the area with sophisticated depots, transfer stations and a liquid waste disposal depot. Documentation has been prepared for a comprehensive industrial waste treatment plant and sites are under investigation. The Branch's annual dinner dance was held on the 17th September at the Sebel Town House, Elizabeth Bay. Over 120 members and their friends enjoyed an evening of fine food and good company and dancing continued until closing time with a large proportion of 'stayers'. A highlight of the night was the presentation of the Water Board Gold Medal for Public Health Engineering to Mr. Robert Mackellar, a student at the University of New South Wales . In making the presentation, the Board's President, Eric Warrell, drew attention to Mr. Mackellar's outstanding academic record and wished him well in his future career. After dinner, the gathering was entertained by Professor Noel Martin, Dean of Dentistry at the University of Sydney who spoke on 'Fossils, fluxes and fluoridation'. Professor Martin said that it was recognized, more than a century ago, that certain fossil specimens were more Jong lasting ,than others and that there appeared to be some relationship with the geology of the area in which they were found. Also, people living in some areas of Europe were found to have teeth that were less prone to rapid decay even though they presented a rather blackened appearance. However, it was not until the 1930s, when suitable analytical techniques had been

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developed , that a connection was established between tooth decay and the intake of fluoride. Further research determined the concentration of fluoride that could provide protection without darkening the teeth. A number of fluoridation methods were tried and the most effective, and cheapest, was found to be the fluoridation of water supplies. Professor Martin concluded an entertaining address with a review of the wide ranging public debate that had; occurred when water supply fluoridation was introduced. On 26th October a combined meeting was held with the Civil Branch of the Institution of Engineers at Milson's Point. A disappointingly small audience of about 50 heard Bob Cadden from the Sewerage Maintenance SubBranch of the Sydney Water Board present a paper on 'Rehabilitation of Sewerage Systems Using the Insituform Process'.

Mr. Cadden remarked that the rehabilitation of sewerage system s is attracting more attention throughout the world due to the potential effects of sewer failure. The various rehabilitation techniques now available have a number of advantages and disadvantages and all have an impact on the environment to varying degrees. When taking all factors into account, the 'lnsituform' process provides an economically efficient method of providing a continuous watertight structural lining in a defective sewer with minimal impact on the community environment. The process is an extremely simple system of placing a reinforced plastic lining into a failed conduit. The choice of resin type used in the liner depends on the type of service required and can be selected from a number of polyester or epbxy resins. A needle interlocked polyester felt is used to absorb the resin, hold it in position, maintain dimensional thickness stability and provide sufficient strength to allow the liner to be placed ihto position in the conduit. Plain felt can be obtained in various thicknesses and weights so that, by building up a number of layers of felt, a liner of any desired thickness can be prepared. Thicknesses may vary from 3 mm to 18 mm in 3 mm increments. The lecture was supplemented by slides and an excellent, 'well-exposed' film. A lively discussion and question session concluded a stimulating evening. On November 16th, a technical meeting was held in the Sydney Water Board Theatrette. Professor Rolf Prince , Head of the Department of Chemical Engineering at the University of Sydney spoke to an audience of about 50 on the subject 'Modelling of the Hawkesbury'.

Professor Prince traced the history of river modelling employing, principally, box modelling techniques and discussed the important work done on the modelling of the Thames estuary. A linear type model had been used to determine the behaviour of the river as the treatment of sewage discharging

ASSOC/A TION to it was improved. By this means it had been possible to determine a relationship between treatment costs and anticipated river water quality improvement. He went on to speak of the modelling work that had been done on the Parramatta River between Homebush Bay and Parramatta Weir using, in this case, boxes on two levels to model vertical sali nity, dissolved oxygen and B.O .D. effects. Professor Prince then discussed briefly the nutrient modelling of the Hawkesbury River but advised that a lot of work remained to be done before the full effects of nutrient discharges could be satisfactorily modelled by his Department. Once again the Branch's Christmas Party was held at the Mandarin Club, this time on Thursday, 25th November. A 10 course Chinese Banquet was provided to make an early season assault on the waistlines of members and over 110 friends. Fred Randie's organising was first class, our President's wife, Fay, provided gifts for the ladies and festivities were still running high when your correspondent left (late!). Visit by Prof. Marais

Gutteridge Haskin's & Davey's Sydney office was fortunate enough to have the company of Professor G v R (Gerrit) Marais recently for an afternoon of technical interchange with the Firm's Engineers and others. Prof. Marais hails from the University of Cape Town and his fields of speciality are activated sludge systems, biological nutrient removal, D.A.F. systems and the basics of lagoon operations. His comments on the South African approach were interesting and instructive, particularly the emphasis placed on COD: • as a prerequisite (together with a 6-8 per cent ratio of TKN) for high efficiency P removal; • for uniform equalized application of loads utilizing a COD algorithm; • as a principal measurement of sewage strength, and a parameter which can be 'balanced' through the plant. Marais' team has developed a computer model for activated sludge incorporating nitrification, denitrification and phosphorus removal, which GHD intends to use at the Penrith (NSW) nutrient removing treatment works augmentation. Prof. Marais is also commencing research on activated sludge bulking. His visit is hopefully a foretaste of closer communication and technical interchange across the Indian Ocean . Coming Events

6th February. A Sunday morning inspection of the Tank Stream, Sydney's first water supply and now a stormwater drain running underneath the Central Business District. Numbers will be limited and old clothing will be required! 16th Febryary. A lecture in the Sydney

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VIEWS

Water Board Theatrette on 'Hazardous Waste Management' by Paul Dougas (Sinclair Knight and Partners) and Errol Samuel (Metropolitan Waste Disposal Authority) following their tour overseas to study these matters. Early March. A lecture by Dr. W. Knisel of the U.S. Department of Agriculture on modelling projects conducted by his Department into the effect of land uses on water quality. Jlth -J5th April. The Tenth Federal Convention (see further details in this issue). May. A lecture by Bob Dixon, Foundation Engineer for the Sydney Water Board, on foundation problems associated with water supply and sewerage structures. NEWCASTLE GROUP

The 15th Annual General Meeting of Newcastle Sub-branch was held in the form of a smorgasbord meal at the Belmont 16 Ft. Sailing Club on Saturday night, 25th September, 1982, at 6.30 p.m. Members and guests were welcomed by outgoing Chairman John Roberts . Official guests were - Dr . J . Paterson (President of the Hunter District Water Board) and Partner, Lance ·Bowen (A WW A NSW Branch President) and Mr. and Mrs. David Ward. Dr. J. Paterson presented David with the Hunter District Water Board's Gold Medallion. David was an undergraduate of the University of Newcastle in I 98 I and received the award for proficiency in Hydraulics and Water Resources. Officers elected for I 983 are: Chairman, Lindsay Black, Sr. Vice Chairman, John Roberts; Jr. Vice Chairman, Brian Clulow; Secretary, Kevin Young; Treasurer, Ian Finney; Committee - John Roberts, Ashley Pepper, Bill Johnson, John Fleming. Dr. J. Paterson, after presenting the Gold Medallion, gave a very entertaining address on 'Water Usage', covering the new 'User Pays' system operating in the Hunter District Water Board area. Twenty three members attended the 59th General Meeting of the Sub-Branch held on I Ith October. Mr. David Anderson Chief Engineer of the Hunter District Water Board and Rex Dengate from the Metropolitan Water Sewerage and Drainage Board covered the topic 'Water Reuse in Australia'. The talk covered the literature search achieved to date, existing water reuse projects, and potential areas that could economically benefit from the use of treated effluents. The 60th Meeting of the Sub-Branch took the form of an excursion to Tomago Aluminium Smelter in the Hunter Valley. Twenty-two members inspected Stage I of the works which is 40 per cent complete. The tour finished in the Education Centre of the plant where the aluminium process was discussed and a light snack and refreshments were provided by the Company.

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COMMENT SOUTH AUSTRALIA

BRANCH ACTIVITIES

At the Branch Annual General Meeting on 24th Septemberr, Bob Clisby was re-elected President and Peter Norman elected VicePresident. Tony Glatz continues as Secretary and Mary Drikas as Treasurer. The new Committee consists of Scott Cameron, Arthur Greenhough, Doug Lane, Brian Maguire, Moss Sanders, Kevi Trevarton and Ralph Wood. The AGM was addressed by Brian Stone, a Perth Consulting Engineer with wide international experience in the water treatment field. His talk 'Water Treatment - Comparing Performance with Design' began with a brief description of the aims of municipal water treatment and he then presented typical stateof-the-art results achic;ved with comment on physical and chemical problems commonly encountered and typical plant performance problems. Hydraulic and process related problems accounted for about 80 per cent of all the performance problems listed. Other less frequent problems involved sludge disposal, corrosion and computer facilities. Problems in plant performance compared with design can be traced to insufficient pilot testing and inadequate checking of hydraulic computations. On 27th September at the Branch Committee Meeting, Brian Maguire was appointed Journal Correspondent for 1983 and Messrs Lane and Clisby were reelected as Federal Councillors., The Committee is pleased to welcome new members, Dr. Calder and Messrs Catalano, Vassiliou, Palmer, Hunt, Van der Wei, Morran, Kilmore, Kracman, Parsons, Spangler and Associate Membels, Messrs Schmidt and Jones. On 2nd November a special meeting heard Dr. Michael McGarry speak on 'Low Cost Technology for Water Supply and Sanitation in Developing Countries'. Dr. McGarry is an internationally ·recognised expert and is a coauthor of the book, "Water, Wastes and Health in Hot Climates". The meeting, arranged at short notice was well attended. Dr. McGarry spoke on the problems facing the period 1981-1990 which has been declared as the international water supply and sanitation decade. Slides provided a graphic insight into the deplorable water supply and sanitation conditions existing in developing countries, with overcrowding, scarcity of water and absence of sewerage and with defecation often taking place in open areas or unhygienic communal pit latrines. Water is often only intermittently available through communal taps with washing and bathing performed in public. Enteric water-borne diseases is devastating, an estimated 25 million children die each year in developing countries from such diseases. Considerable progress was being made in countries such as Thailand and India through community projects that provide safe, WATER December, 1982 9

ASSOC/A TION

hygienic and affordable water supply and sanitation facilities. Funding for such projects is provided by international agencies such as the World Bank, and by the co untries themselves. The success of projects in a community depends greatly on the motivat ion a nd enthusiasm of the local municipality and local contractors. Sanitation problems in India were being overcome through the introduction of the pour-flush latrine provided at one-tent h the cost per household of a conventional sewerage scheme. In concluding his address Dr . McGarry mentioned that the purpose of his visit to Adelaide was to obtain information on the 70 or so common effluent drain age schemes being operated in the State, with a view to possible application in developing countries commencing initially in Pakistan . The 1982 programme ended on an entertaining note with the annual Guest Night held on 12th November, when the guest speaker, Mr. Len Beadell, addressed an a udience of about 90 guests, choosi ng as his topic, 'Too Long in the Bush', the title of one of six books he has published. Mr. Beadell, who has been called, 'the last of the true Australian explorers' is a surveyor cum roadmaker cum explorer and was responsible for making some 6500 km of roads in central Australia . His work in building one of these roads, the famous Gunbarrel Highway, earned him the British Empire Medal award in 1958. He fascinated the audience with the history of his work in the outback of Australia, beginning in 1946 with the surveying of the site for the Woomera rocket range, followed by the site surveys for the atomic bomb site at Emu field and then in later years, the eight year construction of the Gunbarrel Highway. His description was interspersed with en tertaining anecdotes of the numerous adventures he and his team experienced during the many years spent in some of the most arid and isolated parts of Australia. In our September issue we carried a happy group picture of the Minister and members at the Disinfection Seminar. The group included David Martin, a stalwart of the Branch, now retired from the E. W .&S., but we omitted his

10 WATER December, 1982

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name from the caption - black mark to the Editor! Apologies David. To balance the ledger and for all to recognise, here is David Ma rtin as a solo presentation . STATE NEWS

On 7th November, the Premier, Mr. Tonki n officially started site works for the State's newest and biggest (720 ML/d) water filtration plant at Happy Valley. When completed, the $65 million project will provide filtered water to about 40 per cent of the Adelaide metropolitan area, or 180,000 homes, covering the foothi lls to the sea. Included in the proposal are headquarters for the E.&W.S. Department construction and maintenance groups coveri ng the southern metropolitan area. The E.&W.S. Department held an open day on 23rd October at the Christies Beach Sewage Treatment Works to give Adelaide residents the chance to see how a modern sewage treatment plant operates. The open day coincided with the commissioning of the $4.1 million second stage of the works, which duplicates the first stage capacity, and giving now an ep capacity of 100,000. The following week, on 30th October, the Premier commissioned a $12 million saline drainage disposal scheme near Loxton on the River Murray. It is hoped the scheme will reduce salinity levels in the South Australian section of the river by allowing highly saline drainage water from the Renmark, Berri and Cobdogla irrigations areas to be pumped to a natural depresion at Noora for evaporation . The Scheme is part of an overall $60 million project to control salinity levels in the River Murray a nd improve irrigation practices. The fo llowing day the Premier officially opened the new $18 million Barossa Water Filtration P lant with a design capacity of 160 ML/day . This plant, the third of six plants that will ultimately provide filtered water to the entire Metropolitan area, will serve up to 140,000 consumers in the Northern Adelaide plains area. The official opening was an 'open' day for the general public.

VICTORIA BRANCH ACTIVITIES

At the Annual General Meeting on September 15th, after a right royal smorgasbord dinner at the State Rivers, Robin Povey handed over office to Ian Lowther of Geelong, and then presented his retiring President's address. Based on his considera ble experience as manager of the Operator Training Centre, he summarised what he considered to be the areas of concern for water and wastewater treatment in Victoria. Graphic examples of some of these areas were shown in his slides. Thankfully, some of them were in the 'before and after' category. The main problem seems to be the lack of backing for the treatment plants by the City Engineers. This is reflected in safety; staffing levels; process control; operator facilities (and morale) and in checking on performance and equipment. Some system of assessing and monitoring overall performance of the many and varied Au thorities is needed. It will be difficult to

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formu late the cri teria, but Robin recko ns it wi ll be worth it. This sa me point was taken up during the Panel Discussion session during the Sprin g Breakout Conference at Bendigo on October I Ith-13th. T he discussion was so va lu able that a separate report is being drawn up. The conference was held in historic, but dry , Bendigo, and 30 members with wives and fami lies attended, Saturday being devoted to addresses by four speakers. The first speaker, Nei l Burns, Engineer of the Bendigo Sewerage Authority, provided a vivid insight into the problems of maintaining an old sewerage system. His ta lk was libera lly illustrated by footage from the Authority's televi sion sewer inspection progra mme . The Authority's an nual sewer maintenance budget is $150,000 a nd this inclu des very little preventative maintenance. Ingress of tree roots was highlighted as the major single problem causing blockages and increasing infiltration. Bendigo strata is generally 3 m to rock, thus the sewers are shallow . The summers are dry and the trees are thirsty. The Authority experiences up to 40 sewer blockages every week due to tree roots. The tree policy on private property is the firs t blockage free, with a warning that the nex t one will be paid for usually the householder then removes the tree. The peak wet weather flow is six times average dry weather flow. Neil' s paper was a timely warning to all Authorities of the high maintenance costs which can be expected as the sewerage system ages. Lac hl an Campbell, Engineer of Horsham, presented a heart-rend ing paper on the much publicised prob lems of the Horsham Sewerage Authority which is required, by a recent decision of the Environment Protection Appeal Bpard, to cease discharge to the Wimmera River. This cou ld cost Horsham some $3.5 million and conseq uently the case is now being taken to the Supreme Court. The paper illustrated the power of a wellorganised and emotional pub lic campaign in opposition to scientific and economic reality . Lachlan now is haunted by Phragmites A ustralis, the macrophyte which (it is claimed) is enriched by nutrients from HSA so much so that he carries a fine sampl wherever he goes as a warning to the six other Authorities who might have been on the nodischarge hit list (including Bendigo .and Shepparton) but for a 100 mm difference in rainfall. Jonathan Crockett of G.H .&D. then presented an interesting paper on Trends in Sewage Trea tm ent in V ictoria. He highlighted the advantages of lagoons but concluded that newer would be activated sludge and probably of th e race-track type. Biological nitrogen and ph osphorus removal were explained and the first plant in Australia to include them, at Penrith, was described. He also stressed the need for improving design and operation of plants and highlighted the lack of assessment of plant operating efficiency at present. Wayne Drew of SRWSC fi nished the morning with an excellent description of the Eppalock water

quality study. The heavy use of Eppalock for recreation has led to significant physical, chemical and bacteriological pollution with resulting urgent need for controls on further development. Local Councils are pressing fpr more subdivision in the new catchment, but the Commi ssion would like to see such restri cted to one house per 40 hectares. Some of the problems of carrying out such a catchment study were highlighted , in particular the difficulty of timing sampling to co in cide with inflows . Despite these difficulties, th e study has led to a usefu l water quali ty management st rategy. Other highlight s of the weekend included a visit to the Sand hurst Reservoir in course of construction, and the many ;nterestin g tourist features of the city. Despite wi ld dancing on the Saturd ay night , all were up early to join in the lively discu ssion mentioned above. At a join t meet ing wit h the Institution of Engineers in November Dr. M. McGarry, recently of the developments fundin g organisation of the World Bank , now a consultant in the same fi eld, spoke on the problems of water suppl y and disposal of human waste in developing countri es, and the application of appropriate technology. His message, however, was virtua lly th e same as Robin Povey' s. The technology, whether advanced or 'appropria te' is there. The bottlenec k is management. In Dr. McGarry's terms, 'software' must be established before the ' hardware' will work effectively. As we go to press, the Branch Meeting on November 23rd will hear Mr. Graham J. Davies on the related themes of 'accountability' and 'pricing policy' in relation to the water industry in Austra li a. Mr Davies is an Econom ist specialisi ng in the economic, manpower and organisati onal aspects of water and sewerage. The com mittee for 1982-83 is as fo llows: President, Ian Lowther; Vice-President, Alan Howard; Imm . Past President, Robin Povey; Secretary, John Park; Minute Sec., Reg McMillan; Treasurer , Warren Wealands; Committee, Frank Bishop, Alan Strom (Federa l Councillors), Bill Dul fer, Sam Rogerson, Wayne Drew, Prof. Lawson, Peter Nadebaum , John Parker, Bob Swinton, John Scroggie, Roger Payne, Peter Roberts, Roger Vass, Russel Patterson. Alan Longstaff declined re-nomination a fter a number of years as a sterling member of Committee, and so did Ken Wood, Hon . Treas urer for 13 years. Robin thanked Ken specia ll y at the A.G.M. and handed him a token of the appreciation of the Victorian Branch.

AWWA 10th FEDERAL CONVENTION

Sydney,April 11-15

1983 EVENTS

NEWS

SYMPOSIUM ON INTEGllATION OF ECOLOG ICAL ASPECTS IN COAST AL ENG INEERING PROJECTS 6-IOth June-Rotterdam

THIRD RIVER BASIN MANAGEMENT CONFERENCE 4-7th July-University of York, U.K.

NEW CHAIRMAN FOR ANC After a lengthy and busy term Leon Henry steps down and J. S. (Sam) Rogerson takes up the cares of office as Chairman of the Australian National Committee.

Sam, a Bachelor of Civil Engineering (Melbourne) , Engineer of Water Supply and Fellow of the I.E . Aust is Deputy Chairman of the State Rivers and Water Supply Co mmi ss ion of Victoria . After wide ex perience in the areas of major dam construction , urban supply, design and co nstru ction and water a nd sewerage infrastructure management, he became a Commissioner in 1975 and Deputy Chairman in 1977 .

THIRD INTERNATIONAL CONFERENCE ON ANAEROBIC DIGESTION 14-20th August-Boston University SPECIALISED SEMINAR ON RAINFALL AS THE BASIS FOR URBAN RUN-OFF DESIGN AND ANALYSIS 24-26th August-Copenhagen DESIGN AND OPERATION OF LARGE WASTEWATER TREATMENT PLANTS 19-23rd September-Vienna ENERGY SAVINGS IN WATER POLLUTION CONTROL 26-29th September-Paris, France

ROTATING BIOLOGICAL DISCS 6-8th October-Stuttgart 1984 AMSTERDAM CONFERENCE CALL FOR PAPERS-BY NOV. 15, 1983 Further details from Hon. Sec. IA WPRC Box A232, P.O. Sydney South 2001

AWWA

INTERNATIONAL SPECIALISTS CONFERENCE Darwin, N.T. - ' 4-9th Sept. '83 Covering water regime related to mining, milling, waste treatment and rehabilitation with emphasis on uranium mining.

In addition to hi s duties with the Commi ss ion, he serves a number of Governmenta l and Profe ss ional organisations including the Australian Water Reso urce s Counc il , the Env ironme nt Protection Council, th e Land Conservation Council , the Victor ian Water Resources Council and has played an active part in the AWW A, the IA WPRC a nd the Institute of Water Management. His interests have involved numerous overseas study investigations and attendance at IA WPRC Conferences and associated study tours .in addition to technical study courses and a session at the Australian Ad ministrative Staff College. Members of IA WPRC wish Sam a fruitful Chairmans hi p.

BE THERE ... For the com ing year IA WPRC has listed an impressive line-up of intern ational events in cluding:

Enquiries: Secretary, Specialist Conference Committee, P.O. Box 37283, Winnellie, N.T. 5789, Australia.

ODOURS FROM HIGH RATE BIOFILTERS HELP WANTED! The Auckland Regional Authority and the Christchurch Drainage Board both have high rate plastic media filters about six metres deep and both are experiencing odour problems . The N.Z. Ministry of Works and Development would appreciate advice of any similar problems encountered in Australia and any comment on such. Replies to the Ed itor are invited and will be forwarded. WATER December, 1982 11

RECENT OVERSEAS DEVELOPMENTS IN BIOLOGICAL SURVEILLANCE J. F. Skidmore INTRODUCTION This paper summarises the results of a study tour in Europe and North America during 1980. The tour was sponsored by the Office of the Supervising Scientist for the Alligator Rivers Region, the objectives being to observe current developments in biological surveillance and in aquatic toxicology, with reference to the environmental problems in uranium mining in northern Australia. In the course of the tour, 21 laboratories were visited in Britain, Canada, the United States of America and Switzerland . Many of the overseas developments are relevant to Australian problems generally, and an attempt will be made to highlight the most applicable innovations. BIOLOGICAL SURVEILLANCE

Surveillance has been defined as 'a continued programme of surveys systematically undertaken to provide a series of observations in time' Hellawell, 1978, p .2). All levels of biological organisation may be utilised, from cells through organisms to ecological communities. Biological survey methods are generally simple and usually involve the field collection of biological material for subsequent analysis and interpretation in the laboratory. The information obtained may be used to demonstrate the ecological effects of both known physiochemical changes and also of unsuspected and intermittent pollutants . In all four countries visited, biological surveillance is practised to some extent in assessing water quality. Most progress has been made in Britain. Surveillance methods feature prominently in short courses held periodically by the National Water Council on biological aspects of water pollution control. Routine use is made of indicator species, that is to say, of species which provide some indication of environmental conditions, either by their presence or by their abundance or by the accumulation of pollutants. Data on the abundance of a particular organism, or on the diversity of species at a particular site, are generally summarised in the form of biological indices, which may be used in the interpretation of levels of pollution. The best modern review of the literature is by Dr. J. M. Hellawell, now at the Severn-Trent Water Authority (Hellawell, 1978). The presence of a species implies that suitable living conditions have existed throughout the lives of individuals then present, and in that sense provides reliable data concerning the weeks or months prior to the inspection. In contrast, chemical data of water quality refer to conditions merely at the instant of collection. Biological surveys before and after major environmental impacts (such as mining or urban development) can detect quite subtle ecological changes - although natural perturbations of animal and plant populations must first be recognised. However, such surveys can only describe events after they have occurred: they are of no value in predicting changes before they occur. The use of biological surveillance in monitoring water quality in Australia is an obvious application of recent developments in northern hemisphere techniques. The methods are readily adapted for local use . The big difficulty is the lack of taxonomic keys and the scarcity of distribution data for many Australian groups of animals and plants . SIMULATION MODELS OF WATER BODIES

As an aid to the prediction of environmental change, there is at present considerable interest in the USA, Canada, UK, Switzerland, West Germany and Denmark , in the use of model water bodies simulating the natural environment. Such models allow the simultaneous evaluation of several potential levels of man-made stress on a simplified ecosystem. Model streams were visited at the University of Aston in

Dr John Skidmore is a Principal Lecturer in Environmental Biology at the New South Wales Institute of Technology, PO Box 123, BROADWAY, NSW 2007. He is at present working on the toxicity of heavy metals to Australian native aquatic animals. This paper was first presented to the New South Wales branch of the A WWA in January 1981 . 12 WATER December, 1982

Birmingham (Mr. H. A. Hawkes), at Eidgenossische Anstalt fur Wasser, Abwasser und Gewassershultz (EA WAG) in Zurich (Dr. E. Eichenberger) and at the Virginia Institute of Technology in Blacksburg (Dr. A. Hendricks). In the Aston installation, the effects of cadmium and domestic sewage on communities of fish and invertebrates have been compared in three stream s each 300 m long (Balloch , 1977). The EAWAG work is principally to determine the growth rates and species composition of diatoms and other algae in the presence of heavy metals (Wuhrmann & Eichenberger, 1975). Nine channels each 75 m long and six channels 250 m long have been constructed. A combination of low levels of cobalt, zinc and copper was found to be sufficient to cause the total replacement of diatoms by filamentous green algae (Eichenberger, pers. comm .). Model 'lakes' were visited at the University of Rhode Island at Narragansett, RI, and at the Canada Centre for Inland Waters at Burlington, Ont. The installations are refinements of an original concept of Dr . J . W . G. Lund of the Freshwater Biological Association in the early 1970s. He had established vertical cylinders of Polythene sheeting in Lake Windermere, to isolate complete vertical sections of the lake from the general circulation within the lake. The projects at the University of Rhode Island, and at CCIW, are each centred around several robust, free-standing cylinders about 6 m high, containing water and sediments from Puget Sound and from Lake Ontario, respectively. Elaborate measures are taken at Narragansett to simulate tidal exchanges within Puget Sound. The purpose of both projects is to predict the effects of organic pollutants on the respective ecosystems, and on the capacity of the environment to assimilate and biodegrade industrial wastes . At EA WAG, model aquifers up to 30 m deep have been used to predict the ability of natural aquifers to absorb and re-purify lake water polluted with phenolic wastes. Various microbial nutrients have been added to the model aquifers, to investigate the feasibility of recharging the ground water beneath Zurich, for use in the event of nuclear attack . There are probably no Australian projects at the present time which would warrant the expense of model water bodies as elaborate as those just described. However, the concept could be applied quite simply ancl inexpensively through the use of ij0rtable swimming pools. One suggested use is to predict the fate of mining pollutants in billabongs or in other bodies of shallow water, before the actual mining takes place or any of the billabongs become polluted. USE OF TOXICITY TESTS

Prediction of the effects of pollutants on aquatic organisms is most efficient and most economical under controlled conditions within the laboratory. Prediction is the main business of all the aquatic toxicology laboratories in the four countries visited. Up to 30 years' work â&#x20AC;˘ has resulted in the accumulation of numerous and conflicting data on the comparative sensitivity of large numbers of test organisms , under a variety of environmental conditions. This work has recently been reviewed (Skidmore & Firth, in prep.) and shows that the range in sensitivities is due mainly to changes through the life cycle, to the effects of certain environmental parameters (such as water hardness and pH) and to differences between test species . Dr. D. I. Mount of the U.S. Environmental Protection Agency at Duluth, Minnesota, considers species differences to be paramount. He advocates numerous extensive comparative tests of acute toxicity, that is tests of up to seven days' duration under similar and constant conditions, using several prominent species from an aquatic ecosystem at risk, in order to determine 'safe' water criteria. On the other hand, Dr. J . B. Sprague of the University of Guelph advocates the intensive study of a few key species through their life cycle, to identify the most sensitive life stages for determining safe water quality criteria. Dr . D. Hansen of the USEP A at Gulf Breeze, Florida, has pointed out that juveniles and fry are usually the most sensitive stages, but exceptions

have been found, such as inhibition of reproduction in adult fathead The British apparatus was initially developed by Mr. F. S. H. minnows by zinc and copper, and the inhibition of moulting in Abram, now at the Water Research Centre, Stevenage (e.g. Abram, shrimps by pentachlorophenol. 1970) with significant modifications by Mr. D. G . SJilurben, also of It should be made clear that most workers now advocate the use of Stevenage (e.g . Shurben, 1978) . The earlier siphons were activated by chronic toxicity tests (tests of greater than seven days' duration) to . moving floats and kinking tubes . Later, pneumatic power was inderive water quality criteria for toxic substances. Maximum accep- troduced. In recent designs, the delivery of pollutant from large table toxic concentrations - MA TC values - are now generally hypodermic syringes is controlled by computer tape. The apparatus is preferred in framing regulations for northern hemisphere countries. very reliable and accurate over several months through a wide range of These values are based on a var iety of lethal and non-lethal tests ; the flow rates, but requires substantial expertise in manufacture. Diluters use of acute toxicity tests plus application factors has now been largely may be purchased from Measureite Ltd., of Royston near Stevenage, superseded. U.K. 'Brungs 's apparatus' (e.g . Mount & Brungs, 1967) is an all-glass The selection of available toxicity tests, and of more subtle bioassays of non-lethal responses to pollutants such as growth and diluter without.moving parts, and has been adopted by the USEPA, avoidance, has now become quite extensive, and was discussed at the by CCIW, by the Ontario Water Resources Branch, and gy several International Associ.a tion for water pollution Research workshop on North American contract laboratories. It is very reliable and fairly acecotoxicology at Toronto in June 1980. Chronic tests of survival, curate through several months, but required skill in glass cutting and growth and reproduction of brook trout in the presence of heavy several weeks' adjustment before toxicity tests. It is not suitable for metals have been continued through three generations for up to 1200 low flow rates. Working drawings are available from USEPA, Duluth days at USEPA, Duluth (e.g. Holcombe et al., 1979). Generation tests (Lemke et al., 1978). At the Virginia Institute of Technology, and at with microcrustaceans and algae are naturally far briefer (e.g. Bies- Beak Consultants Ltd., of Toronto, the siphons have been replaced by inger & Christiensen, 1972) . Work at the Water Research Centre, solenoid valves. Stevenage, U .K . on the comparative sensitivity of British freshwater At USEP A, Narragansett, the dilution apparatus is devised from fish to heavy metals (Cooper & Solbe, pers . comm.) is very similar in rather expensive peristaltic pumps plus header tanks. Apparatus of aim to parallel work on Australian freshwater fish and invertebrates at this type is technically simple, is suitable for all flow rates, and is reliable and accurate for experiments of several days' duration. Failthe New South Wales Institute of Technology. At CCIW, Hodson (pers . comm .) has shown that low levels of lead safe devices either cut off the water supply in the event of power can decrease metabolism in trout (for example, by inhibiting appetite) . failure, or disconnect power if the water fails. Similar equipment has Work at USEPA, Narragansett, RI, suggests that low concentrations been independently developed at the New South Wales Institute of of cadmium may disrupt metabolism in barnacle larvae, causing ab- Technology. normal moulting or decreased activity. A major interest of Dr. J. A simple modification of the Mariotte bottle has been described by Conch at USEP A, Gul f Breeze, Florida, is in the pathobiology of Leduc (1966) and used successfully in Dr. J. B. Sprague's laboratory tumour induction by aquat ic pollutants . The 'International in Guelph, alongside Brung'.s apparatus. It is particularly useful in the Musselwatch' programme sponsored by USEPA assays the bioac- field, provided that a constant flow of dilution water is available. A cumulation of pollutants in marine mussels, and the growth of simpler development of Brung's apparatus, also without moving transplanted and self-estab lished mussels, in field tests lasting several parts, has been devised by Dr. D . Benoit of USEP A, Duluth (Benoit et weeks. This program has included Australian workers and will be al., 1982). It is particularly useful for accurate and long-term studies discussed at a workshop to be held in Canberra on 22 November 1982. with low rates of flow. It is normally made of glass, but is being An assay of the growth of the shell rim in oysters, devised by Dr. P. fabricated at N.S.W .I.T. using Perspex, and is recommended for field Butler of USEPA, Gulf Breeze, is now a routine toxicity bioassay con- and laboratory use in Australia . ducted by EG and G Bionomics at Pensacola, Florida (Mr. R. Parrish, · Test animals in use overseas are not recommended for routine use in pers . comm_.). Dr. R. W. McCauley (pers . comm .), of Wilfred Laurier Australia, because none of them occur here naturally. A few interna· University has compared CTM (critical thermal maximum) values for tional reference species are obviously necessary, to attempt to standarseveral species of fish. This approach is of particular relevance to dise the performance of different test laboratories, and to compare the work in northern Australia, where pollution can be expected at sensitivities of different test species . Two widely adopted reference species are rainbow trout (Sa/mo gairdnen) and zebrafish temperatures very close to the upper lethal limit. In the light of overseas experience, predictions of pollutant toxicity (Brachydanio rerio), and both are in use at the N.S.W.I.T. Rainbow in Australia can best be made initially by comparing the sensitivities of trout have been widely introduced into cold waters in south-eastern representative test species in acute toxicity tests . This should be Australia, are sensitive to many chemicals and are regularly used in followed by chronic tests both lethal and sublethal, aimed at identify- cool water toxicity tests in U.K., U.S.A. and lanada. Zebrafish have ing critical stages in the life cycles of sensitive species . Work on the ef- not been introduced into Australia, but are freely available through fects of environmental parameters (hardness, pH, temperature, the aquarium trade from Singapore. They are of intermediate senalkalinity) has largely been completed for northern hemisphere toxici- sitivity, are widely used in warm toxicity tests in many countries, and ty problems, but the results are not much help in predicting toxicity in are easy to breed in the laboratory . They were first used in toxicity Australia, where environmental conditions are often outside the work in Australia in 1963 (Skidmore, 1965). Both trout and zebrafish ranges tested in Europe and north America. For example water are recommended by the Organisation for Economic Co-operation temperatures regularly reach 38°C at Jabiru, NT, with total water and Development (OECD), which has issued provisional protocols for hardnesses as low as 4 mg CaCO,/ L, whereas there are few toxicity fish toxicity tests in all countries . Copies of the protocols are available data world-wide for temperatures above 25°C, or for hardnesses from Mr. I. Carruthers, Department of Home Affairs and Environbelow 30 mg CaCO,/ L. It is suggested that work in Australia should ment, Canberra. be aimed at extending previous work, not repeating it, so that the world literature·may be utilised in attempting to predict toxicity under DISCUSSION AND CONCLUSIONS Australian conditions. Biological surveillance of environmental impact is a valuable In every country, the earliest toxicity tests have been static, with the test solutions unchanged during the test. Such tests are simple to ar- method of detecting subtle ecological changes after they have occurrange technically, but are unstable chemically, because of progressive red. Northern hemisphete methods are directly relevant to Australia, changes in pollutant concentration and composition. Metabolites but northern hemisphere species of aquatic animals and plants build up. Continuous-flow tests, in which the test solutions are chang- generally do not occur here. Many Australian species have yet to be ed regularly are therefore necessary to maintain acceptable, stable, described. Application of surveillance methods depends on the prior chemical conditions . They have led to design of complex dilution ap- development of taxonomic keys and distribution data for Australian paratus, in which a stock solution pollutant is mixed with a constant species. flow of dilution water to produce a suitable range of test concentraThe use of model water bodies to simulate natural ecosystems has tions . made great progress in both Europe and America. Through the addiDilution apparatus was developed independently both in Britain and tion of potential pollutants, it is possible to predict their environmenin America. In both countries, it consists essentially of pollutant and tal impact before pollution occurs. The use of simulation models is exdiluent being mixed intermittently by gravity and discharged by siphon, pensive, but it is suggested that the use of portable swimming pools without the necessity of electric power. A failure of water supply may be of value in Australia, to predict the impact of mining wastes suspends the siphon, allowing temporary continuation as a static test. on billabongs and other bodies of shallow standinjl water. WATER December, 1982 13

The most valuable predictive method in aquat ic tox ico logy is th e use of toxicity tests within the laborator y. A vast amount of data has bee n accumulated in the last 30 years, co ncern ing th e tox icity of comm on pollutants to European and American species of aquatic animals. Fish have been mainly studied , under a vari ety of enviro nmental co ndi tions. Generally, newly hatched fry have been the most sensit ive life stage. Elaborate inethods have been refin ed, whereby th e required test conditions can be mainta ined und er continu ous flow fo r long periods. The north ern hemisphere results cann ot be directly app lied to Australia, because the test species are largely unrepresented here and because tem perature, water hardn ess and ot her environmenta l condi tion s in Australia are not always within the range of avail able data. Three approaches are suggested for Austra li an studies in aquatic toxicology: (I) A comparison of the sensitivities of representative native species in acute tests . (2) The identification of critical li fe stages of sensitive species in chronic tests. (3) The extension of work on the effect s on tox icity of environmental parameters, under the extremes of Australian conditions. The design of dilution apparatus is the most critical tec hnical feature of aquatic toxicology laboratories. For work in perma nent laboratories, a modification of the new diluter developed by Dr . D. Benoit is recommended for Austra lia n use. For work in field laboratories, the Mariott bottle is recom mend ed, as used a t the University of Guelph. ACKNOWLEDGEMENTS I wish to thank all those colleagues and institutions mentioned in the text for their generous provision of information, and for their hospitality. Facts have been checked from published records as far as possible. Any errors are my own . I also wish to thank Mr. R. M. Fry, Supervising Scientist for the Alligator Rivers Region , for financial support in North America. The

study tour was made whilst I was on stud y leave from the New South Wa les Institu te of Technology. REFERENCES ABRAM, F . S. H . (1970). Automatic water mixing device . Lab. Proc. / 9: 915-916. BALLOCH, D . (1977) . Effects of a n oxidised sewage effluent on freshwater fisheries. Summary report 1974- 1977. 11 9 pp. Uni. Aston , Birmingham , U.K. BENOIT, D. A., MATTSON, V. R. & OLSON , DIANE L. (1982). A continuous-flow mini-diluter system for toxicit y testing. Wa ter Res. / 6 (4) 457-464. BIESINGE R, K. E . & CHRISTIENSEN , G. M . (1977). Effects of vario us metals on survival, growth , reproduction and metabo lism of Daphnia magna. J. Fish. Res Bd Canada, 29, 169 1- 1700. H ELLA WELL, J. M. (1978). Biological surveillance of rivers. 332 pp. Water Research Centre, Stevenage. HOLCOMBE, G . W. , BENOIT, D. A . & LEONARD, E . N. (1979). Longterm effects of zinc exposure on brook trou t (Salvelinus /ontinalis) . Trans. Amer. Fish. Soc. 108: 76-87 . LEDUC, G. ( 1966). Une bouteille a debit constant pour petit s volumes de liquides. Nat. Can. (Que) 93: 6 1-64. LEMKE , A. E., BRUNGS, W. A. & HALLI GAN, B. J. (1978). Man ua l for construction and operation of toxicity-testi ng proportional dilut ers. U.S. Environ . Protect. Agency , Dulu th. Repo rt No. EPA-6PP/ 3-78-072, 70 pp. MOUNT , D . I. & BRU NGS, W. A. (1967). A sim plified dosing apparatus for fi sh toxicology studies. Wat. Res. I: 2 1-29. SH UR BEN, D. G. ( 1978). A self-brea king concent ric siphon dosing apparatus. Lab. Pract. Feb. 1978. SKIDMOR E , J . F. (1965). Resistance to zinc sulphate of the zebrafi sh (Brachydanio rerio Hamilton-Buchanan) at different phases of its li fe history. Ann. Appl. Biol. 56: 47-5 3. SK IDMORE, J . F. & F IRTH , I. C. Acut e sensitivi ty of selected Australian freshwater an imals to copper and zi nc. Aust. Wat. Resources Cou nci l Report, in prep. WUHRMANN, K. & E IC HENBE RGE R, E. ( 1975) . Experiments on the effects of inorganic enrichment of ri vers on periphyton prim ary production . Verh. lnternat. Verein, Limo!. / 9: 2028-2034.

TECHNICAL INTERESTS Bond, H. Lawson , J. Malone and G. Williams , Prof. W. Musgrave, M. Lindner, K. Idle and R. Rollinson . Enquiries: Dr R. Wheway, Dept. of Mechanical Engineering , University of Wollongong (042) 28 2460.

ADVANCE NOTICE

AWWA FIFTH SUMMER SCHOOL Canberra, 6-10 Feb., 1984 Selected themes are: • Assimilative capacity of lakes and streams for effluents . • Monitoring and modelling of urban waterways. • Unit processes for wastewater treatment.

water

and

INTERNATIONAL MEMBRANE SYMPOSIUM Preliminary Announcement SYDNEY - 8-10th Nov. '83

• Finance and management for the water industry.

Coverage will be the widest possible range in Membrane applications and fun damental research .

Further information: AWWA Summer School Cl· School Applied Science, Canberra College of Advanced Education, P.O. Box 1, Belconnen, A.C.T. 2616.

Papers sought: new developments in reverse osmosis, ultra filtration, crossflow fi ltration, dialysis , electro dialysis , facilitated gas transport and gas permeation .

WRFA SYMPOSIUM

Applications may include water and waste treatment, biochemical processes, biomedical , food and dairy industry, separations in chemical and mining industries etc .

ENERGY AND ECONOMICS IN WATER UTILISATION Univ. of Wollongong-Feb. 25th

Speakers are from the private and Departmental spheres and include: K. 14 WATER December, 1982

Official call for papers in December, abstracts due May 1983. Further information: Dr. A. Fane or Prof. C. Fell, School of Chem. Eng. & Ind. Chemistry, University of N.S.W., P.O. Box 1, Kensington 2033.

CHURCHILL FELLOWSHIPS 1984 The Churchill Trust now invites applications from Australians 18 years and over from all W5'lks of life for fellowship s tenable in 1984. Fellows are provided with return economy class overseas air-tickets and living allowance for approved overseas study projects. Potential applicants should apply now for the Trust 's Information Brochure to: Winston Churchill Memorial Trust (M) , P.O. Box 478, Canberra City, A.C.T. 2601 . * • • * COLORADO UNIVERSITY

DESIGN OF WATER QUALITY NETWORKS June 13-17, 1983 Short course in development of monitoring networks determining am bient water quality and assessing trends.

Emphas is on groundwater monitoring automatic sampling and analysis procedures. Enquiries: Thomas G. Sanders, Program Leader, Environmental Engineering , Dept. Civil Engineering , Colorado State University, Fort Collins , Colorado 80523, U.S.A.

YOUR FEDERAL CONVENTION-APRIL 11-lSth INTERNATIONAL CONTENT "At the present time about 1. 2 billion people of the world population suffer from disease caused directly by drinking contaminated water or by the insanitary waste water installations ... up to 70,000 human beings die of these diseases every day - 25 million per year ... " T hese words by Maarten Schalekamp , the Director of Zurich's Wasserversorgung (Water Supp ly), introduce a bookl et on this fascinating authority which must be one of the most forward thinking in the world. The man driving this dynamic organisation is a keynote address speaker at A WW A's Federal Convention in Sydney on II-15th April. Maarten Schalekamp is also President of the International Water Supply Authority, Chairman of th e Swiss Water and Gas Association and the President of th e World Ozon e Society. His keynote in Sydney will concentrate on the various prob lems faced by the Authorities around the world in providing sa fe water with particular reference to Europe, where water recycling is common . Ozonation, his other love, wi ll be the topic of another address and is bound to attract di scussion of the fears of so me specialists of chlorination of partially treated water. During a recent whirlwind world business trip which took in eight countries in less than four weeks, and included a bout of the 'flu and two IO-hour train journeys through du sty and hot central India, Mike Dureau , Managing Director of Kent Instru ments (Au stra li a) Pty. Ltd., visited Mr. Schalekamp at hi s Z urich headquarters w h ere Maarten Schalekamp hosted his visit, and even mustered an Australian flag to fly beside the flags of Switzerland and of the Water Authority.

Maarten Schalekamp

The Groundwater P lant Hardof spreads out behi nd the cheery blue mu lti-storey administration centre which looks across the Limmat River to hillsides coated with vineyards. A wa lk around the plant is in park-like surrounds. Over 150,000 square metres of green zones and sports facilities cover the underground water extraction plant and only the top of the maintenance building and garage is obvious. The bores and the Control Room are in Nuclear proof

underground concrete caverns which ensure that th e capacity of 150,000 mJ per day is guara nt eed even und er wart ime cond it ions a str iking co ntrast with war-torn Beirut where safe water is worth more than go ld . The water is co nstantly monitored by a wide range of ana lyti ca l instrum ents as well as very sop histicated biological watchdogs (fish). The activity levels of a tank full of fi sh exposed to the water flow are monitored and alarms are raised if the fish become too sluggish (or too active?). The sin gle operator too, locked away in hi s command ce ntre, is monitored in case of sickness or accident. The control room is dominated by a huge map of Switzerland and a mimic of the water network and any feeling of isolation is relieved by pleasant art.ificially lit gardens behind glass at each end of the room.

ment processes with remarkable results and Dr. L. Van Vurren, Assistant Director of the National Institute for Water Research in South Africa, where sewage is purified so thorought ly that it can be co nsumed - a nd is. Joining these wor ld greats are spea kers from Egypt, Japan , England, Germany, Thai land , Sweden a nd New Zea land and th e U.S.A. Our third key note speaker, John H . Stacha, the 1983 President of the powerful American Water Works Association, will address the Conference on Water Quality and Treatment Activities in the .S.A. Surprisingl y, John Stacha is a Geological Engineer, but thi s Texas waterman has a long career with A WW A and other Water Association s such as WPCF, th e Texas Water Conservation Association and the Texas Water Utilities Association.

Dr, R. F. Packham

In a different sp here Dr. Ron Packham, a Director of the Water Research Centre in Medmenham, England, continues his studies into the relationships between water quality and heart disease, the results of which have won him world wide acclaim. The quiet country-s ide hides a sprawli ng bui lding bristling with the most sophisticated electronic equipment studying vaporised mo lecu les and feedin g data into constantly chattering banks cf computers. This keynote speaker at our International Con Ference is no ordinary water researcher. Among his many degrees and international honours he has a Ph.D. in Electro Chemistry from the University of London and a postDoctorate Research Fellowship in Applied Chemistry at Harvard University. His two papers will concentrate on the hea lth aspects of drinking water with special emphasis on the heart, but he wi ll be available for discussion on water quali ty. The magn ificent line up of Australian speakers at the Conference and the high standard of our local authors will add to the presence of such world authorities as W . Wesley Ekenfelder Jnr. of the U.S.A., who first applied his discipline of Chemical Engineering to Water and Waste Water treat-

John H. Stacha

The organising committee hopes you wi ll do all in your power to come to this heavily subsidised Convention - your Convention - and have des igned the programme so that you can: • Hear a top line up of Austra lian and Internat ional speakers . • Challenge the tenets th ey proclaim in lively discuss ion by sending out preprints before the Con Ference for you to study. • Choose between a stream concentrating on water qua lity and one on waste water treatment. • See a wide cross-section of manufacturers' exhibits, including instrumentation, treatment equipment, pipes and pumps. • Meet and share your problems , solu tions and opportunities with up to 400 other delegates in the same fie ld as yourself many of them key decision makers. Come along - make the effort - this will be a Conference that will be ta lked about for years to come. All Sydney based members are waiting to welcome you to dur beautiful city by the sea. WATER

December, 1982 15

EXTENDED AERATION TREATMENT OF SALINE W ASTEWATERS L. Appelgren 1.00

INTRODUCTION

Part of the water suppl y for a north Queensland tourist resort island is derived from a shallow bore system which draws freshwater from a Ghyben-Herzberg lens ie a lens of freshwater floating on salt water. At the beginning of the year after the monsoon season, the water from the bores is fresh, but, as the source is depleted during the year, the quality deteriorates due to sea water intrusion. This effect manifests itself as an increasing salinity in both the island' s water supply and wastewater. Increases in salinity can be observed up to the onset of the next monsoon which very quickly recharges underground freshwater supplies. A reduction of salinity (as TDS) from 12 000 mg/ L to 700 mg/ L has been observed over 12 hours from the commencement of the heavy rains. Investigation s to improve the potable water supply on the island are continuing but these have not been encouraging, particularly in economic terms, and it is considered probable that there may always be a requirement for the sewage treatment plant to treat saline wastes. A new treatment plant is to be constructed and this study was undertaken to determine whether a treatment process could be adopted which would be capable of adapting to an increasingly saline wastewater and also adjust quickly to a non -saline wastewater. Topographic constraints on the island necessitate that the new treatment plant be very compact. Therefore, initial process investigations have concentrated on the activated sludge treatment process. 2.00

LITERATURE REVIEW

Some previous investigations on the effect of high or variable salinities on the activated sludge process have been reported. Stewart, Ludwig and Kearns (1962) studied the effect of seawater on an extended aeration pilot plant to assess the applicability of this process for the treatment of shipboard wastes. Temporary reductions in treatment efficiency were noted when severe changes in salinity were combined with heavy hydraulic and organic loadings. It was observed that the mixed liquor sludge concentration continued to increase after a freshwater to seawater change but the concentration decreased temporarily when the seawater was replaced with freshwater. Ludzack and Noran (1965) investigated the effects of chloride concentrations (as NaCl) up to 20 000 mg/L on the activated sludge process. It was found that increasing salinity stimulated the oxygen uptake rate. In general, high chloride concentration led- to -decreases in flocculation and -

Lex Appelgren is an Associate of Ullman and Nolan Prop. Ltd., Consulting Engineers, Mackay, Queensland. 16 WATER December, 1982

oxygen-demand removal efficiency . Kincannon and Gaudy (1965) found, in a batch activated sludge study, that high chloride concentrations (as NaCl) could cause a severe decrease in substrate removal rate. Longterm exposure to high salt concentrations caused a significant change in the ratio of respiration to synthesis. In a later study, Kincannon and Gaudy (1966), found that an activated sludge developed in a freshwater medium was less drastically affected by a slug dose of salt than were sludges developed in high salt concentrations by a rapid change to a freshwater environment. The effect of the shock variations (0-45 000 mg/ L and vice versa) was an immediate release of cellular components. Burnett (1974) operated a bench-scale activated sludge plant that was subjected to salinity variations reaching 37 000 mg/ L NaCl, and it was observed that the plant did recover its treatment ~fficiency_ albeit slowly. Grigg, Shatrosky and van Eepoel (1971) carried out an investigation of the operating efficiencies of package plants on the island of St. Thomas in the Virgin Islands . It was found that two of the best performed plants were satisfactorily treating wastes of widely varying salinity. 3.00

BENCH-SCALE STUDY

A bench-scale study with an activated

sludge plant operated in the extended aeration mode was undertaken to assess the treatability of the anticipated wastewater at the isl;rnd-resort. 3.1

EXPERIMENTAL APPARATUS

A schematic diagram of the experimental plant is shown in Figure I. The feed solution was pumped into the outer cone of the 6.6 litre aeration chamber. Re-circulation of the MLSS was achieved by an airlift action around the inner cone. Compressed air was delivered to the plant at a rate of 150 litres/ hour. Effluent was removed from a central cylindrical clarifier (44 mm ID) at an

(1) (2) (3) ,(4)

Air Supply Air Diffusers Aeration Chamber Settling Cylinder

(5) Feed Supply Line (6) Sludge Wastage Line (7) Effluent Removal Line

Figure 1. Experimental apparatus.

average velocity of 4.8 to 5.5 m/ day. The hydraulic detention time in the plant ranged from 19.5 to 23.7 hours. Apart from effluent solids and MLSS samples no sludge was intentionally wasted from the system. The experimental work was carried out in a 20-22Â°C temperature controlled environment. TABLE 1: COMPOSITION AND CHARACTERISTICS OF SYNTHETIC WASTEWATER Constiruent C, H,,O, (NH,), SO, Mg SO,.7H,O Mn SO,.H,O Fe Cl,.6H,O Ca Cl, KH, PO, K, HPO, Tap water BOD, pH

Concentration

Day I-Day 31 mg/L

Day 36-Day 47 mg/ L

500 00 250 50 5 0.25 3.75 263.5 535 to volume 357 7.45

440 250 50 5 0.25 3.75 263 .5 535 to volume 314 7.41

Table I lists the constituents and characteristics of the synthetic wastewater used in the experiment. The feed became contaminated between Day 32 and Day 36 and the available oxygen-demanding substances were reduced to as low as 266 mg/ L BOD,. Although this was unintentional, it did serve to simulate the dilution of waste strength due to high wet weather infiltration which occurs simultaneously with the ~hock change to a non-saline waste. The waste strength was intentionally reduced after Day 36 to model the effects of wet weather infiltration. Seawater sali11ity of 34.10 g/ kg was prepared from the constituents given in Table 2 and is based on a published seawater ion analysis (Armstrong and Miall) and two analyses made at the island by a consulting analyst. The seawater was diluted to produce a feedwater salinity of 17 000 mg/ L as TDS. 3.2

OPERATION

The bench-scale plant was seeded with MLSS from a municipal plant and the experimental apparatus operated on a nonsaline feed for 3 weeks to prove the process and acclimatize the sludge. The whole apparatus was then stored in a cold room for 4 TABLE 2: CHEMICAL COMPOSITION OF SIMULATED SEAWATER Consrituent

Concentration mg/ L

Na HCO, Ca Cl, KCI NACI

134 1,154 716 27 153

Mg Cl,

2 390

K,CO,

14 3,419

Mg SO,

days prior to the experimental period. From Day l to Da y 16 a non-saline feed was used to allow th e sludge to furth er acclimatize. On Day I 8 the feed water salinity was in creased to 17 000 mg/ L and the saline feed continu ed until Day 29. From Day 30 to the end of the test period , a non -saline feed was used .

= ....

120

CJ) CJ)

5"' t-

w :::,

3.3

Generally analyses were carried out in ac·cordance wit h Standard Methods. The exception being that the BOD dilution water was brought to the same salinit y as the environment from which the seed organisms or unseeded effluent was taken. A comparison of BOD tests of the feed having the same glucose concentration, in saline and non saline periods, revealed comparable results. A number of invest igations have been carried out to determin e the effects of salinity on the BOD test e.g. Gotaas (1949) , Kess ick & Manchen (1976), Davis et al (1978). Generally, it has been found that the oxygen demand of the particulate matter is reduced in saline wastes and that there is a gradation of this effect with increasing salinit y. In this experi·ment, the effect of reduced demand of the particulate matter was observed . The BOD test method adopted for fi ltered of soluble wastes was confirmed by comparison of TOC data and known carbon concentrations. 4.00

RESULTS AND DISCUSSIONS

Figures 2 and 3 show the variation of test results throughout the experimental period. 4. I

..J

ANALYSES

Effluent suspended solids

From Day I to Day 16 the plant was essentially attaining a steady state performance but the carryover of suspended solids (SS) was always less than 30 mg/ L. It seems probable that the effluent SS concentrations in this period were larger than would normally occur for the same settling velocity. The feed salinity and settling veloci-

u.. u..

w 18 _

7000

6000

::::

1/0

e MLVSS

1 u

5000

w :::, ..J

CJ)

ty from Day 38 onwards·was similar but the effluent SS did not exceed 8 mg/ L. It is considered that the suspended solids washed out in th e ea rli er period were non -v iab le organisms. This explanation is suggested by the slow rate of increase of mixed liquor concentration during the Day I to Day 16 period . Also, during thi s earl ier non -saline period, the SVI decreased from a value of 190 at the outset to 150 at Day 16. The wash out of dead cells is a li kely explanation when ii: is-further considered that the sludge had been stored for several days without feed in a cold room prior to the start of the testing programme .

u.. u.. w

'g' 8 0

Salinity

....:

:::,

CJ)

..J

z ..J <(

u.. u..

"' >-

Filtered T0C

--------70:..

§ ~

•

CJ)

TIME ( Days )

/o "'E

Figure 3. Mixed liquor and effluent suspended solids variations throughout experimental period.

IIl

5"'

•

I ..-+--.~-----------.

Cl 0

g"'

= ....

....

Salinity

0 MLSS

T IME ( Days )

Figure 2. Variation of effluent organics throughout experimental period .

The cells may have undergon e endogenous metabo lism, possibly to the point of sta rvation and death. Durin g the saline feed per iod, i. e. Day 17 to Day 30, the effluent SS concentrations were considerably greater ·than during both non-saline feed periods. However, it is seen that the SS washout was decreasing as the exposure period increased . The reason for the damped oscillations in effluent SS is not apparent, but it is possible that this was due to changing spec ies dominan ce in the MLSS. The washout of SS was I'lot at its most severe during the shock changes in salinity. The maximum SS values occurred about two days after the beginning of the salinity changes. The reseatc h of Kincannon and Gaudy ( 1966), Kincannon et al (1966) and ot hers indicates that lysis of cellular constituents will occur after an osmotic shock. After this cell lysis the sludge will contain a proportion of empty cell membranes which have poor settli ng character. The loss of these membranes over several days is a likely explanation of the increased effluent SS values after sal inity changes. Eckenfelder (1979) has noted that high salt concentrations result in poor sludge flocculation with consequ ent high effluent SS carryover from sedimentation tank s. 4.2

Effluent organics

Effluent organics were measured as filtered TOC, filtered ·BOD, and total or unfiltered BOD, . Inhibition of the oxygen demand of suspended solids has been shown to occur in saline environments and the usefulness of total effluent BOD, data during the saline period may therefore be considered a doubtful measure of the organic effluent material. The filtered effluent TOC values have remained essentially constant at about 10 mg/ L through the saline and non-saline periods. An increase to 29 mg/ L was observed on Day 33 WATER December, 1982 17

i.e. after th e fres hwat er shock. This in crease

wou ld be due to th e release of solub le lysate and indi cat es that severa l days might be required for recovery of trea tm ent effi ciency after a fr es hwat er shock. Severa l days after th e fr es hwat er shock the fi ltered or soluble BOD, also in creased but not to the same extent as the TOC . The reco rded TOC for Da y 33 ma y indica te that a greater upset in treat ment efficiency occurs th an is indi ca ted by th e filtered effluent BOD, . ThÂˇe total efflu ent BOD, at thi s time is more than 40 mg/ Land reflects th e effect of th e high suspended solids co nt ent. It is noteworth y that the total and filtered effluent BOD, had both reduced to pre-s hock levels wit hin a week. Th e exerim ent al work indi ca tes that, apart from a short loss of treatm ent efficien cy after th e fr es hwater shock, a plant operated under these conditions wou ld provide adequate reduction in solubl e BOD, in both saline and non -sa lin e environments . Durin g period s of operation on sa lin e wastes, th ere wi ll be a hi gher ca rr yover of suspended solid s but thi s wou ld not necessa ril y be reflected in a total effluent BOD, test beca use th e oxygen demand of SS in sa lin e wa stewaters is inhibit ed. Kessi ck a nd Manchen (1976) also mention thi s phenomenon . 4.3

Aera tion chamber slud ge behaviour

Both the MLSS and MLVSS co ncentration s have been plotted as lin ear in creases from Da y I to Day 32 and from Day 36 to Day 47. The ava il able data do not co nclu sively support a lin ear increase of sludge co ncentration but they do show greater co ncentration s during the saline feed period than before it , and a marked in crease in the rate of sludge production after the return to a non sa line feed. Microscop ic examination in the pre-s a lin e period id ent ifi ed significant numbers of sta lk ed and motil e ci li ates. During the sa lin e feed period, the stalk ed ciliates were still observed but they were small and relatively inactive. The SV I of the MLSS was initially I 90 indicatin g poor sett ling characteristics. By Day 16 the SV I had decreased to 150 . During the saline test period , th e SV I achieved a steady va lue of about 70 indi cating improved settling character. The SY ! in creased temporarily to 100 after the freshwater change and then continued at a steady value of about 75. The relatively slow increase in sludge concentration through the pre-salin e and sa line periods may be due to low initial numbers of viab le micro-organism s in the sludge or the low operating food to micro-organisms (F/ M) (kg BOD,/ kg MLVSS.day) ratio during the experim ent. 4.4 Operating load and treatment efficiency Table 4 details the operating load and treatment efficiencies achieved by the benchscale plant and these are considered to be typical for the extended aeration process. 5.0

CONCLUSIONS

It has been shown that a viable MLSS can be susta ined and will achieve satisfactory treatment in a saline environm ent of 17 000 mg/ L (as TDS) but sudden changes of salin ity will cause temporary losses of treatment efficiency. References-Continued on page 24 18 WATER December, 1982

CALENDAR 1983

May 9-13, Perth, W. Aust. 53rd ANZAAS Congress.

January 5-7, Jaipur, India. 9th Nationa l Co nven tion on Environmenta l Engineering. Âˇ

May 16-20, Brisbane , Queensland Annual Scientific Meetin g, Soc. of Microbiology .

January 16-19, New York, U.S.A. Meeting of Water Pollution Contro l Federat ion.

May 23-26 , Perth, W. Aust. Geochem ica l Exploration in Arid and Deeply Weathered Environments.

February 25, Wolongong, N.S.W. WRFA Symposium - Energy & Economics in Water Uti lisation.

May 23-27, Florence, Italy 1st World Congress on Desalination and Water Reu se.

February 27-March 3, Jeddah, Saudi Arabia Water Technology in th e M iddle East, 1983 .

May 30, Baltimore , U.S.A. Groundwater Flow and Solu te Transport in Fractured Rock s.

March, Queensland , Aust. Conference on Coastal Engineeri ng . March 1-4, Mexico City Aqua Mex. '83 Int. Water Technology Ex and Conference (Water Decade 1981 / 90) . March 1-5, Mexico City, Mexico Int. Water Technology Ex hibiti on . March 6-10 , Dubai, U.A.E. Arab Water T echnology Exh ibiti on ' 83. March 7-10, Melbourne, Vic. Work shop on non-point so urces of pollution in Australia . March 10-13, Milan, Italy Aquatec, Italia and Geotec. March 14-June 17, Kensington , N.S.W. Grad. course in hydrology-U niv. of N.S.W. March 19-25, Melbourne, Victoria 25th Australian Survey Congress. March 21-25, Darwin, N.T. Agro-Research for Australia's Semi-Arid Tropics. March 29-31, Cambridge, U.K. Pumps-The Heart of the Matter. March-April, Queensland, Aust. Eng . Conference on Tunnelli ng. April 10-17, Crete Environmental Impact Symposium . April 11-15, Sydney, Aust. AWWA 10th Federal Convention . April 12-15, Manchester, U.K. W.R .C. on Stabilization and Disinfection of Sewage Sludge. April 25-26, Kansas City, U.S.A. Wind and Solar Energy Technology. April 25-26, London, U.K. Conference on Control of Exposure to Hazardous Materials . May 2-6, Noordwijkerhout, N'lands Int. Symposium on Methods and Instrumentation for the Investigation of Groundwater Systems.

June 5-8, Florence, Ital~ 1983 Conference of Int. Federation of Consulting Engineers . June 20-22, Basie, Switzerland 2nd European Conference for Construction and Maintenance of Pipelines. July 11-15, Sydney, N.S.W. Sem inar-Management of Toxic, Hazardous and Intractable Wastes (Univ, of' N.S.W.). July 12-14, London, U.K. Congress, World Water '83 . July 15-26, Hamburg, Germany Int. Symposium and Work shop on Hydrological Applicat ion of Remote Data Transmission . August, Newcastle, N .S. W. Computers in Engineering Hydraulics and Fluid Mechanics. August 12-16, Hobart, Tasmania Aust. Surveying Assoc . with Inst. of Mining & Eng. Surveyors.

August 14-19, Perth, W. Austra lia So lar World Congress. August 15-27, Hamburg, W. Germany Hydrological Appli cations of Remote Sensing and Data Transmission . September 4-9, Darwin , Northern Territory Specialised Conference on Water Regime and the Uranium Industry. September 12-16, Brussels, Belgium Aqua-Expo, 1983 & IWSA Exhib ition. September 19-22, Brisbane, Queensland 2nd National Local Government Engineering Conference. October 5-7, Amsterdam, Netherlands Oxidation Ditch Technology. November 30-December 2, Canberra, Australia Symposium on Prediction in Water Quality . December 5-9, Sydney, N.S.W. Int. Conference-Groundwater and Man.

PERTH UPGRADES TREATMENT PLANTS SUBIACO

WOODMAN POINT

The Perth Metropolitan Water Authority (MW A) engaged Consultants Camp Scott Furphy Pty . Ltd. (CSF) to undert ake detailed design documentation , tender documents and co-ordination of construction for a multiphased redevelopment program for year 2001 loading. Estimated cost is $22 m at 1981 prices. Current average inflow to Subiaco WWTP is 41 MLD, with TSS and BOD 5 of 10,400 and 13,300 kg/ d respectively. These are projected to increase to 61.4 MLD , 15,400 and 19,300 kg/ d respectively by the year 2001. Almost every facility within the plant is to be upgraded. Major works including: • New pretreatment facilities. • Upgrading and expansion of the existing aeration faci lities. • High-speed ce ntrifuga l blowers for aeration air co mpression. • Upgrading and expansion of seco ndary clarifiers, using vacuum sludge removal. • New chlorination facilities including pre and post chlorination control a nd postchlorination for disinfection . • Waste activated sludge thickening. • Upgrading and expansion of the existing two-stage anaerobic digestio n faci lities. • New mech a nica l slud ge dewatering facilities. • Distributed process control facilities for plant operation and monitoring. • Upgrade of the power supp ly system throu ghout the plant. Discharge of effluent to the Indian Ocean via the existing outfall is to be conti nued , as is blending of dewatered digested sludge with soil to produce a so il conditioner (by a commercia l enterprise). A major consideration is the h igh tem perature of wastes in summer (up to 30°C) with accompanying nitrification. Accordingly, provisio n will be made for nitrification in the design of aeration faci lities. Incoming was tes can be extremely sept ic, with total su lphides up to 12 mg/ Land odour has been a problem . Pre-chlorination is working effectively at present and the M.W.A. is conducting tests on use of pure oxygen injection into gravity mains as an alternative. The primary cause of plant odours was insufficient oxygen in the aeration system and the inability to quickly remove settled activated sludge from the secondary clarifiers. Interim modifications have temporarily relieved the problem and the proposed upgrade wi ll provide permanent relief. In conj unction wi th the upgrading of the plant, the primary treatment facilities at Swanbourne W.W.T.P. wi ll be abandoned and flows ct iverted to Subiaco . The Subiaco plant is to be ugraded over the next four and a half years, with a staged development of individua l facilities to enable a reasonable cash flow over the proposed redevelopment period. A complex combination of day labour and contract construction

Construction of Extension I of the Woodman Point Wastewater Treatment Plant to cater for the population growth in the southern suburbs of Perth bega n in August 1981 and is now well under way wit h completion of physical work sched ul ed for the end of 1982 and handover in April / May I 983. Estimated value of the completed works is some $ 11.5 million. The plant consisting of primary treatment faci lities is designed to handle 125 MLD by the year 200 1. Provision is made in the plans and site a llocations for a seco ndary treatment. As a res ult of the Metropolitan Water Authority's recent decisions, the primary wastewater will be di scharged from the Cape Peron ocean outlet. Facilities now under co nstruction include two automatic bar screens, two grit chambers wit h grit removal systems and four primary settling tanks. Screenings will be pressed bagged and transport to incinerators located at other plants. Present proposals also allow for grit to be buried and skimmings to be pumped to th e exist ing di gesters. Sludge is to be transferred to th ese di gesters and after digestion will be pumped to the existing dr ying beds for drying and sale as a fertilizer. An Administration Building will house staff offices, control room, data acquisition equipment and an extensive laboratory. Located nearby is the Amenities / Maintenance building which includes staff amenities, first aid, workshops, overhead crane and storage areas. A network of roads allows' for ready access to all major structures. Considerable care has been taken to blend the extensions into the existing terrain a nd at the co nclusion of the civi l work s, considerable planting will be undertak en to complete the landscape . Principal consultants for the project is the Joint Venture of GHD-Dwyer (W .A .) Pty. Ltd. in association with Consoer Townsend Harri s International, Inc. of Chicago. Contractors for the project are Transfield W.A .) Pty. Ltd .

Primary digester under construction.

is being undertaken in order to max imize use of available speciali zed construction and insta llation labour within the M.W.A. The works involved are divided as fo ll ows: • Individual supply co ntracts for all major eq uipment items. • Installation of equi pment and associated piping and serv ices by the M. W .A. • Civil construction (including ta nk s, siteworks, yard piping, channels) by the M.W.A . • Ind ividual co ntracts for construction of most buildings. Staging of construction and spread of the work between seve ral contractors and M.W.A. day labour forces with a multiplicity of design and construction activities involves major respo nsibi lities for Camp Scott and Furphy in co-ordination to ensure minimum effect on plant operation. Contracts have been let for chlorination facilities and the ch lorination building by co ntract is proceeding, completion is due by the end of 1982. Civ il works associated with an additiona l primary anaerobic di gester have been comp leted by the M. W .A. Gasholder covers are now in hand. The M.W.A. will clean out the existing digesters while eac h is out of serv ice for cover modifications . This wi ll be the fir st "clean out" of the digesters since their comm iss ioning 20 years ago . ALLEN J. GALE

H. McKENZIE Woodman Point WWTP under construction.

WATER December, 1982 19

WATER FILTRATION USING LOCALLY AVAILABLE SAND Olusola Ogedengbe ABSTRACT

It is now being said that Technology cannot be tran sferred ; that it can on ly develop in a socio-eco nomic framework. This cou ld ac. count in part for the fact that sand and gravel used in rapid filters in the water works of many Third World Countries are imported (as well as the Treatment plants). The study reported herein attempts to deter mine whet her, and to what extent sand from different local sources are suitable as filter media , and to use a less cumbersome mode of sand specification than 'effective size' and 'uniformity coefficient'. Each of the three sand sources studied (river sa nd , erosion sand, and common sand) yielded more than 50 per cent of silica sand stock in the size range ~0.3 mm. Turbidity removals and headloss development were good. INTRODUCTION

Every set of water treatment equipment and spare parts used in most developing countries of the world is imported from a more technologically advanced country. In all cases known to this author (mostly in Nigeria), the treatment package delivered into the recipient country includes several tonnes of sand to be used in the filtration unit of the water treatment plant. And although a few are now resisting the temptation to do so, many Water Works Management Authorities use imported sands every time replacement is necessary. This situation shou ld be of concern to both the developed a nd developing countries. It is not necessary to ~ait and see whether optimization studies would show that local sands would cost less to obtain (it is reasonable to expect that this would be found to be so). The psychology in importation of sand is bound to develop into a dominant negative factor , which unfortunately, could lead to over-reaction in terms of use of sand and gravel whose hydrau lic and filtration characteristics would be questionable. There is a need therefore to undertake (or sponsor) research into the performance potentials of sands from va rious local sources as filter media so that recommendations can be made on their preparation and use. Conventionall y, filter sand is specified on the basis of 'effective size' and ' uniformity coeffi cient' . The term 'effective size' (0 10 ) seems to have derived from tests (Hirch, 1945) indicating that the size which separates th e coarser 90 per cent from the finer 10 per cent of the sand controls the hydraulic behaviour of the filter. The uniformity coefficient (Uc) is the ratio of the sand size separating the coarser 40 per cent from the

Dr Ogedengbe is Acting Head of the Department of Civil Engineering at the University of Ife, Ile-Ife, Nigeria. 20 WATER December, 1982

finer 60 per cent, to the effective size (i.e.

o••l O,o) , a nd is a meas ure of dispersion . The ranges of 0, 0 a nd Uc commo nly used in rapid filters are 0.35 mm -0.55 mm a nd 1.3-1. 75 respectively (Babbit et al, 1967, ASCE et al, 1969, Fair et al, 1971) . However, these probably reflect predominant filt ration practices in the USA, as there are indications that wider ranges (Uc up to about 5, for instance) are allowable. The use of 0, 0 and Uc as yardsticks for measurin g useability of a sta ndstock in filters can be quite cumbersome. It is relat ively easy, given a stock of sand , to determine its effective size and uniformity coefficient; and , on the basis of these, accept or reject the sand or suggest that its grade-co mpo sition be modified. The process of modifying the grade compos ition of a sand stock, to a given set of specifications of 0, 0 and Uc is not so easy. It is certainly not as easy as suggested in the standard instruction - 'Sc reen off the coarse and washout the fines' . It might help encourage local suppliers of sand and gravel therefore, if use of 0, 0 and Uc co uld be deemphasized in filt er media specifications . The current study is to be viewed as part of

RUBBER HOSE TO PUMP

efforts needed to encourage use of local sands and gravels. The enti re project is planned to be in three phases as fo llows: (a) to identify local sources of sand and gravel, wash and screen them to establish what proportions are useable, based on tu rbidity removal and headloss development; (b) to develop a simple system for wash ing and screening (grading) large quan tities of these materials quickly; and (c) to study overall fil tration and backwashing characteristics in relation to grade compositions so that an econom ic analysis could be made. This write-up is principally a report on the fir st phase of the project. (Work on the 2nd phase is at an advanced stage , a simple screening machine being now under construction) . Specifically, it was intended to determine whether, and to what extent, sands available locally are suitable for use as filter media. It was a lso intended to see if a simpler characteri sation can be used in lieu of (or along with) 0, 0 and Uc in fi lter design specifications. MATERIALS AND METHODS

Materials used included sa nd and gravel from different local so urces, meta lli c

- -- - RUBBER HOSE WITH CLIP ~==:::;-::,=---SAMPLING PpRT ~

HEADLOSS PORTS

f"" (..._ _ _ _ _...s.::;:t=:=-- FLOAT VALVE PLAN

50cm 7-5cm

- - - -HEADLOSS PORT

( 2)

(9 -2 4cr 15cm THE FILTER BOX SAND (60-75cm )

25=<D<56=

ERFORATED PIPE UNDER DRAIN

5·6mm < D < 12-5mm~ Figure 1 -

The components of the filter unit.

materials for con struction of filter box and underdrains, and raw water from a damimpoundment. The ma in act ivities, or operations involved were; procurement, washing and grading of sand and gravel, construction and cha rging of filt er box, preparation of influ ent water, and filtration and data co llection. Based on experience in the local construction industry three main sources of sand were identified; namely, sa nd from rivers (river sa nd), sand which is deposited by storm water (erosion sand), and sand which is found from deposits near seaso nal swa mps (common sand) . A tipper-lorry-load of each type of sand was procured. A tipper load of gravelly soil (locally called 'bush gravel') was also procured. Representative samples of the sand y and gravelly soils were washed t horoughly a nd subj ected to routine tests of speci fic gravity and solubility in 10 per cent hydrochloric acid. These were essentially to confirm what apparently were good quality silica sand s and gravel. . Approximately 1. 1 kg of each soil (air dri ed) was over-dried for 24 hours at I 10° C. One kg of this was weighed into a small handwoven basket (made of palm branches) which had been lined with layers of wire-nettings . This arrangement enabled the so il sample to be washed clean (usin g ta p water) and thus be rid of its soluble components as well as silt a nd sand passing 80 mesh (0.18 mm) . The clean samples were then dried and graded using sieves ranging from 50 mesh (0 .297 mm) through 18 mesh (1.0 mm) for sands and 2.56 mm through 12 .5 mm for gravel. The percentage of each grade found in each was calculated. The standard sieve analyses were performed and D, o, Uc obtained. Filter box was constructed from galvanized iron 2/32" (1 .59 mm) thick. Detai ls of the box are shown in Fig. I . Important features include a float -valve to ensure constant head filtration and an underdrain unit consisting of a galvanized iron pipe perforated on both sides along its length (10 mm holes 10 cm on centres). In placing the filter -media into the box it was decided to keep the height of gravel constant and to vary the height and gradation of sand. Accordingly, in all tests, the bottom 7 .5 cm of tank height were filled with gravel of sizes passing 12.5 mm but retained on 5.6 mm sieves, and the next 15.0 cm with gravel of sizes passing 5.6 mm but retained on 2.56 mm sieves . Depths of sand used were varied between 60 cm and 75 cm; and sand gradations included varied combinations of particle sizes sorted from amongst those passsing 1.0 mm and retained on 0.30 mm sieves. One important constraint in the use of the filter box as constructed was that it had no facilities for backwashing. To ensure a reasonable level of particle segregation (smallest particles at top and coarsest at bottom) every batch of sand taken from the 0.3 mm-1 .0 mm stock was first regraded by sieve nos 18, 20, 30, 40 and 50 (i.e. 1.0, 0.85, 0.59, 0.425 and 0.30 mm) into near uni-sized subbatches . The filter box was half-filled with water and rocked gently as the media were . added in small amounts (starting with the coarsest sub-batch).

TABLE 1. CHARACTERISTICS OF FILTER MEDIA FROM DIFFERENT SOURCES

Colour

Odour

River sand

Erosion Sand

·common'

Moist Dry

Light brown Grey

Brown Brown

Light brown Grey wit h brown specs

Moist

None

No ne

dry

No ne

None

of decomposing vegetables None

2.59-2 .66

2.63-2.65

2.61 -2.67

2.65-2.69

Speci fi c gravi ty ranges (3 tests)

Bush gravel

Sand

Dark grey Dark grey None None

mean

2.66

2.64

2.65

2.66

OJo yield : 0.18 < d < 0.30 mm 0.30<d<0.425 mm 0.425 < d < 0. 59 mm 0. 59<d < 0.85 mm 0.85 < d < l.0mm l.0 < d < 4.75 mm 4.75 < d < 12.5 mm l2.5 < d < l9 .0 mm d > 19

12.4 10.6 12 .0 13.4 9. 1 8. 1 6.0 0.0 0.0

13 .8 14.0 10.5 17.0 14.2 9.3 8.9 0.9 0.3

11.7 9.0 4.2 9.4 12.3 16.4 2.5 0. 2 0.0

0.1 0.2 2.4 4.0 6.0 19.3 41.2 4.4 2.0

Useable sand (.3-1.0) Useable gravel (4 .75- 19.0)

45 . I OJo 6.00/o

55.70/o 10. I OJo

34.90/o 2.70/o

12.60/o 45 .60/o

T otal useable mate ria ls (0.3-19.0)•

59.20/o

75 .I OJo

54.00Jo

79.60/o

• The pe rce ntage shown for 'Total useable materials' include those in the range I.0 < d < 4.75 whi ch is probably on ly marginally useable.

The influent water for the filter was prepared as follows: A half-ta nkerfull of raw water from the Opa Water Works (the Water Works of the University of Ife) was drawn into a tank just outside the laboratory. Preliminary laboratory experiments had indicated that the optimum alum dosage for coagulating the water was about 50 mg/ L if the pH was first adjusted to about 8.5 (50 mg/ L of alum lowered the pH from 8.5 to approximately 7 .0). Rapid mixing had also been found to be good in the velocity gradient (G) range 200 sec- • to 600 sec-•, provided that for the high velocity gradients a good amount of flocculation (slow mixing, G of about 25 sec- ') was mandatory. Measurement of velocity gradients was by use of a Master Servodyne (Product of Cole-Parmer Instrument and Equipment Company, Chicago, Illinois, U .S.A.), using Calibration curves similar to those used by O gedengbe (1975). On the basis of the preliminary tests, coupled with the desire to have a fairly turbid filter influent, the influent water was prepared by using a n alum dosage of 50 mg/ L ; rapid mixing at a G-value of 500 sec-• for 2 minutes; providing no slow mixing; and settling for 10 minutes. The supernatant was collected into a box from which a one Horsepower pump lifted the water into the filter box through the float-valve . The effluent control valve on the filter box was set to pass between 100 litres/ mini m' and 150 litres/ mini m', with filter media in place (at the beginning of the filter run) . This choice was based on the fact that rapid filter s are operated at flow rates ranging from 2 gpm/ft' (81 .6 litres/ mini m') and 6 gpm/ft' (244 .8 litres/ mini m' ) as many published works have shown (Cleasby and Baumann, 1962; Fair et al, 1971, ASCE et al, 1969; and so on). During filtration , the turbidity of the influent water was measured every 30 minutes (or less when deemed necessary) on a HACH Turbidimeter, m·o del 2100A. The turbidity of

the efflu ent was similarly measured . Flow rates were measured at about the same time that turbidity samples were taken . Headloss readings were also taken as the difference between the water levels at the top and bottom headloss ports. Whenever each run was terminated , the tank was washed and the media were replaced by the next batch of clean, graded gravel and sand. A filter run was terminated (generally) when the turbidity increased to about 1.5 NTU or when head loss reached about 100 cm. RESULTS AND DISCUSSIONS

Table I shows the physical characteristics of sand and gravel from various sources and the ranges of sizes c,f their particles after those smaller than 50 mesh (0.30 cm) had been washed off. It can be seen from the table that, of the three types, erosion sandstock provided the highest sand yield (55 per cent useable sand, 10 per cent useable gravel). The river sandstock yielded about 45 per cent sand , 6 per cent gravel; and the 'common' sand 35 per cent sand and about 3 per ce nt gravel. On the other hand, the 'bush gravel' yielded about 13 per cent useable sand and 48 per cent useable gravel. Furthermore, each of the four stocks yielded between 8 per cent and 20 per cent of media in the size range 1.0 mm to 4.75 mm which, though not strictly filter sand nor filter gravel, could be useful nonetheless . When particles of sizes equal to or larger than 1.0 mm were eliminated from the stock sa nd (as well as sizes smaller than 0.30 mm), the analysis of the resulting stocks were as shown in Table 2. The values of the uniformity coefficient (Uc) for the river sand, the erosion sand and the common sand were 2.67, 2.69 and 2.95 respectively. The results obtained when a 60 cm depth of sand representative of each of those described in the preceding section (passing 1.0 mm sieves but retained on 0.30 mm sieves) was WATER December, 1982 21

TABLE 2. SIEVE ANALYSIS OF "USEABL E SAND" FROM EACH SOU RCE River-sand

Erosio n-sand

Common-sand

Sieve No. (US)

Sieve opening, d. (mm)

% retained

Cummularive % pa,sing

% rerained

Cummulative % passing

% rerained

Cummulative % passing

18 20 30 40 50 Pa n

1.00 0.85 0.59 0.425 0.30 0. 18 d 0.30

14.09 20.74 18.58 16.4 1 19. 19 10.99

85.9 1 65. 17 46 .59 30. 18 10.99 0.00

16.80 20. 12 12.43 16.57 16.33 17.75

83.20 63.08 50.65 34.08 17. 75 0.00

20.43 15.61 6.98 14.95 19.44 22.59

79 .57 63.96 56.98 42.03 22.59 0.00

100

Effective size• Unifo rmit y coefficient •

100

0.29 2.67

0.26 2.69

0.22 2.95

• Obtained from plots of "OJo passing" vs diame1er (nOI included in 1his ma nusc ript).

used to filt er the pretreated water, a re prese nted in Fig. 2 It ca n be seen that all the three sa nd stocks are ge nera ll y good filt er media, reducing a n average influ ent turbidit y of about 9.5 NTU to less th a n 1.0 during about 7 hours o f filtra ti o n. The general shape of th e head loss curves is somew hat diffi cult to describe. It appears to be a co mbinat io n of ex ponential in crease a nd declining in crease . Cleasby (1968) states that expo nenti al (concave upwards) curves indi cate stron g surface remo val characteri stics. On th e ot her ha nd , the declinin g aspect of the curves may reflect the fa ct th a t th e fil tration rate was not constant (it declined with time).

A\IERAGE FILTRATION RATE;-105 LITRES /min / m 2

AVERAGE INFLUENT SAND

ffi

The turbidity removal characte ri stics o f the ri ver sa nd a nd th at of th e comm o n sa nd could be sa id to be simil a r , a nd better than the removal charac teri st ics of th e erosio n sa nd . However, head loss development is lesser in the lat ter . Th ese results a re what o ne could have expected if th e sand stock used in the erosio n fi lter bed was coa rser. T hey were, however, no t coarser, judging by the analys is shown in Tabl e 2, no r did they look no ti ceab ly more angular (a lth o ugh it did seem as if th e river sa nd was slightl y more sph eri ca l). Bo th th e sudden deterioration in effl uent qu a li ty a nd th e increase in headloss at a bo ut th e 4th hour of filtration through the

TURBID! TY :- 9·5 NTU

DEPTH :- 60c m

SANO SIZES PASS 1mm , RETAINED 0·3mm

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CONCLUS IONS AND RECOMM EN DATIONS Based on th e results of thi s stud y, it can be stated that locally availab le river sand, erosion sa nd and 'common' sa nd are capable of yielding large quantities of high qua lity sili ca sand in the size ranges suitable for water filtr a tion ; that a sand depth as low as 60 cm can produce good qua li ty filter effluents for sands pass in g 1.0 mm sieves but retained on 0.30 mm sieves, without creatin g excessive headlosses; a nd tha t coarser sa nds (passing 1.0, retained on .425; or pass in g 1.0, retained on 0 .59) co uld be used if sa nd depth s exceed 70 cm and 75 respecti vely. It would seem then that filter sands from these sources could be specified simply in terms of sizes passing sieve No 18 (1.0 mm) and those retained on sieve No 50 (0 .30 mm). However there is need for caution in making specifications in this manner, especially where co nstractors are concern ed. The danger is that a specification such as 'passing l mm and retained on 0.30 mm ', for example would seem to be satisfied by sand stocks: (a) passing 1.0 mm, retained on 0.425 ; (b) passing I mm , retained on 0.59 mm; (c) passing l mm, retained on 0.85 and so on. Ob viou sly sand in category c, though it meets that original specification, is not likely to make a good filter medium. It might be better therefore to specify that the sands be supplied in separate bags, involving at least two different ranges of sizes. For example, one might ask for X tonnes of sand of sizes passing 1.0 mm , but retained on 0.59 mm , and Y tonnes of sizes pass ing 0.59 mm but retained on 0.425 mm. These wou ld be easy to check when the sands are delivered. They would , indeed, be easier to produce by a local contractor, than sand specified in terms of D, 0 and Uc. With the likelih ood that hetero-sized sand would be used under this arrangement, it beco mes imperative to segregate sand par-

15 :t:

'co mm o n' sa nd were due to a sudden increase (by a factor of 1. 3) in t1'e fi ltrat ion rat e, arisin g from a sudden o penin g of th e effluent valve. A sudd en increase in fl owrate cou ld res ult in an increase in shea r fo rce, crea tin g a shock a t th e surface of the filt er suffi cient to brea k the surface deposit. A 'free-way' effect co uld thu s be created for improperl y filtered wa ter to go through. Th e quality subsequent- · ly improved so mew hat. Th ese findin gs are similar to those of Cleasby el al (1963). Figure 3 summarises a set of runs in whic h some of the fin er particles from the 'common' sand stock were removed and the sand depth varied. It can be seen that for these relatively coarse sa nds, turbidity removal improved ge nera ll y with time in the durati ons of the runs. However the fact that turbidity was relatively high during the first few hours of each run is undesirable. It seems to ta ke two to three hours for flocculent solids in the influent water to be deposited within the media , where they apparentl y aid ed filtration . Assuming that the maximum desirable residual turbidity is set at 0.8, then it ca n be sta ted that for sands made up of part icles pass ing 1.0 mm sieves a nd retained on 0. 59 mm sieves, the sand should not be less than 75 cm. For sands passing 1.0 mm a nd retained on 0.425 mm , a sand depth of 70 cm seems satisfactory.

0·2 HEAOLOS S CURVES TURBIDITY

CURVES 6

TIME ( HOURS ) FILTRATION RATE WERE GENERALLY ABOUT 120 LITRES/minlm2 AT BEGfNING, ANO DECLINED TO ABOL)T IOOLITRES/min lm 2 AT END, EXCEPT FOR INCREASE BY FACTOR OF 1·3 FOR COM'<10N SAND AT THE FOURTH HOUR Figure 2 -

Variation of turbidity and headloss with filtration time .

22 WATER December, 1982

C LEASBY , J. L. (1968). Facts about filtration of water through granu lar filters. Engineering Resea rch In stitut e, Iowa ~ate Un iversity (ER l-326) Ames, Iowa . CLEASBY, J. L. and BAUMANN, E. R . ( 1967). Selectio n of sand fi ltration rates. Jour-

1-5 AVERAGE FLOW RATE: 90 LITRES/m in lm2

• •

nal of American Water Works Association 54

(5), 579-602. CLEAS BY , J. L. , WILLIAMSON, M. M. , and BAUMANN, E. R. ( 1963). Effect of fi ltration rate changes o n quality. Journal of American Water Works Association, 55, (7), 869-880. FA IR, G. M ., GEYER, J. C. and OKUN, D. A. (197 1) . ' Element s of Water Suppl y and Was tewater Disposal' . J . Wiley , Lo ndon, Engla nd. FOX , D. M . and C LEASBY , J. L. (1966). Experimental evaluat ion of sand filtration theory .

Journal of the Sanitary Engineering Division, Proceedings of ASCE, (5), 61-82.

10 X

::::, I-

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HIRSC H , A. A. (1945). ' Manual for Waste Wate r Plant Operators'. Chemical Publishing Co. Inc. New York, USA. HSIUNG, K. Y. and CLEAS BY , J. L. (1968). Prediction of filt ration performance . Journal of

a5 a:

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Sanitary Engineering Division, Proceedings of ASCE, 94, (6), 1043- 1069. HUANG , J. Y. C. and BAUMANN , E. R. (1971).

0·5

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•

Least cost sand filt er design for iron removal.

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Journal of Sanitary Engineering Division, Proceedings of the ASCE, (2), 171- 190. IVES, K. J. (1964) . Progress in filtration . Journal of A merican Water Works Association, 56,

(HOURS)

THE HEADLOS.S VALUES WERE LESS THAN 0 ·6METERSINALL RUNS FOR THE DURATION USED AND THEFEFORE 'NERE OF LITTLE CONCERN .

Figure 3 -

1225- 1232. IWASAK I, T . (1937) . Some notes o n sand filtration. Journal of A merican Water Works Association, 159 1- 1597. OGEDENGBE, 0. (I 975). The performance of polyelectrol ytes and high velocity gradients in the treatment of wastewaters. Water Research, 10, 343-349.

Effects of varying depths and graduation of common sand on turbidity removal* .

tides in a new filter bed so that the smallest particles are at the top and the coarsest at the bottom. According to Amirtharajah (1970), segregation is an intrinsic property of fluidi zation of filter beds. If so, it would be mandatory to fluidize a new filter bed (by passing water upwards through the under'. drains until the bed expands - as if intending to backwash) before the start of a new filtra· tion cycle. As stated under ' Introduction ' this study is to be viewed as part of efforts to encourage use of loca l sands in filters in the developing countries. It is still a long way from providing all the answers needed. For example the problems in vo lved in washing and sieving large quantities of sand (from loca l sources) are enormous , especi ally because of the constraints in infra-structural faci lities in most Developing. Countries. Moreover, more filtrati on data should be collected using sands and gravel from the se sources; and backwashing studies need to be carried out on them, before proper cost-effectiveness analysis can be made. Further efforts should also be made towards evolving improved and more straightforward param eters to aid, if not to replace, D, 0 and Uc. Finally , one might suggest th at manufacturers of water treatment pl ant equipment which supply Developing Countries en-

courage use of local filter media, even before all th e answers are in. Experiences gained in the local environment wou ld be ex tremel y important in a field which seems to have defied efforts at performance prediction (Iwasaki , 1937; Ives, I 964; Fox and Cleasby, 1960; Hsiung and Cleasby, 1968; Huang and Baumann , I 97 !). ACKNOWLEDGEMENT

The author wishes to acknowledge the co ntributi on of Mr A. A. Adeyekun, in the construct ion of the filter box and preparation of some of the filter media. Use of Uni versity of I fe Research Fund No 14.24EG is gratefull y ack nowledged.

REFERENCES AMIRTHARAJAH, A. (1970). Expansion of graded sand filter s during bac kwas hing, Unpublished M.Sc. di ssertation, Iowa State University, Ames, Iowa, USA. ASCE, ANWA and CSSE (1969) . 'Water Treatment P lant Design', American Water Works Association Inc ., New York, USA. BABBIT , H . E ., DOLAN D , J. J. and C LEA SBY, J. L. (1967). 'Water Supply Engineering' . McGraw-Hill Book Company, New Yo rk , USA.

RULES FOR WRITERS! The following to augment the more mundane 'Advice to Authors' available from your Editor: • Shun and avoid the employment of unnecessary, excess extra words. • Make certain all ' sentences are full and complete. If possible . At all costs , avoid cliches as you would the plague. • Take pains to spell and pucntuate correctly" .

•

BE Consistent. Don 't approximate. Always be more or less precise. • Sedulously eschew obfuscatory hyperverbosity or prolixity. Avoid pointless repetition, don't repeat yourself unnecessarily . • Observe, in all written expression, it is , of the foremost qualification - if not, certainly not or less than - at least definitely secondary then, the importance, of whenever possible trying , so that when , except where is cannot be avoided and/or in further necessary to omit, yet , remember without fail (for this must not be underestimated) to be brief and clear. This is vital. • •

•

Alzwys remmeber to be accurate nea t and carrful. WATER December, 1982 23

BOOK REVIEW THE RESTORATION OF THE TIDAL THAMES-Leslie 8. Wood. Ada m Hilger Ltd , Bristol 1982, 195 pp. The "clean up " of th e River Thames is amo ngst the most frequently quoted examples of the successful appli cation of water po llution control techniques . Thi s book describes the water quality changes whi ch have taken place in the tidal Thames between the Roma n occupat ion of Engla nd and 1980. The early chapters document the first deterioration of the Thames between 1800 a nd I 850, and its sub sequ ent restoration which resulted from a co-ordinated approach to effl uent disposal. The second deterioration and restoration, covering the years 1900 to 1980 (for wh ich consid erab ly more water quality inform ation was avai lab le) are described more technically , and the formation of water quality standards a nd their legislative implications are also discussed. The latter two chapters of the book descr ibe further measures to be taken to im prove the Thames water quality and also the future fl ood control of the river. T he book also contai ns six appendixes whi ch set o ut t he principals of river purification , sewage treatment and disposal, legislative procedures, hydrography, a nd mathematical modelling. T he account of cha nges in the water quality of the T hames up to 1900 is both entertaining a nd informative . It clearly illustrates the still pertinant problem of persuading organisations to take action over water quality matters. The description of the period 1900 to 1980, with its greater technical content is less readable and does not maintain the promise of the earlier chapters . T he last two chapters are a disappointment as they fa il to develop many of th e ideas, such as the introduction of a salm o n fishery, expressed earlier in the book, a nd offer very few predictions as to the future of the river. Consequent ly th e book is neither a general biography of a famous r iver, nor a technical text, but t reads a n uncertain middl e path between the two. Nevertheless , the history of the Thames a nd the two efforts made to solve its pollution problems are of much interest. This book offers, perhaps, the on ly complete account of the water quality cha nges which have taken place over centuries in this most well kn own , well used a nd sometimes well abused river. 8. BOWLES

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'DISINFECTION OF WATER SUPPLIES' Current practice, technology and effectiveness, side effects and alternatives as discussed by the speakers panel. Limited supply of proceedings available - speakers notes and papers at $6.00 per set. Enquiries: A. Glatz, E. & W.S. Private Mail Bag, Salisbury, 5108. (08) 258 1066. 24 WATER December, 1982

L. APPLEGREN Continued from Page 18

COMPANY ANNOUNCEMENTS

REFERENCES APHA , A WWA , WPC F. Standa rd Methods for th e Examina ti o n of Water a nd Wastewater. ARM STRO NG , E. F . & M IA LL , L. M. Raw Materials fro m the Sea. Const ru ct ive Publications Ltd , Lo nd on . BURNETT , W . D. ( 1974). The Effect of Sa lini ty Va riati ons on the Ac tivated Sludge Process. Water & Se werage Works, Ma rch 1974. DAV IS, E. M ., BISHOP , J. R., G UTHRI E, P . K. & FORTHOFER , R . (1 978) . Proba ble Causes for Reduced BOD T est Resul ts in Hypersaline Wastewaters. Water Research, Vo l. 12, 1978. EC KE NFELD E R, W . W . (1 979). P ri ncip les of Wa ter Quali ty Manage ment presented a t ' W as t e wate r Tr ea tm ent: D es ign a nd Operati on' , a continuing edu cat io n course at Surfers Parad ise, 19-23 Marc h 1979. GOT A AS , H . B. (1949). The E ffect o f Seawater o n the Biochemica l Oxida tio n of Sewage. Sewage Works Journal, Vo l. 2 1, No. 5, September 1949 . GR IGG, 0. I. , SHATROV SKY , E. F. & VA N EEPO E L, R . P . (1979) . Opera ting Efficiencies of Package Sewage Pla nt s on St Tho mas , v. i. August-September I 970. Caribbean Research Centre o f the Co llege of the Virgin Isla nds, May 1971. KESS ICK, M.A . & MAN C H E N, K. L. (1 976). Salt Wa ter Do mestic Was te T reatment. Jo urnal WPCF, Vol. 48, No . 9, September 1976. KINCA N NON , D. F. & GAUDY , A . F. ( 1965). Biological Respo nse to Salt Co ncent ra tio ns. Southwest Water Works Journal, Vo l. 47, No . I , A pri l 1965. KINC A NNO N, D. F . & G AUDY, A . F. ( 1966) . Some Effects of Hi gh Salt Concentrati ons on Activa ted Sludge. Journal WPCF, Vo l. 38, No. 7, J uly I 966 . KINCANNON , D. F ., GAUDY , A . F . & GA UDY , E . T. (1966) . Sequentia l Substrat e Removal by Acti vated Sludge a ft er a cha nge in Salt Co ncentration. Biotechnology & Bioengineering, Vol. VIII , 1966. LUDZACK, F . J . & NORA N, D. K. (1965). Tolera nce of High Salinities by Co nve ntional Was tewat er T rea tment P rocesses. Journal WPCF, Vol. 37, No. 10 , O ctober 1965. STEWART, M. J ., LU DW IG , H . F. & KEA RNS , W. H . ( 1962) . Effects o f Varying Sa linity on the Extended Aera tion Process. Jo urnal WPCF, Vol. 34, No. II , Nove mber I 962.

DROUGHT TIMES TWIN PROBLEMS Water shortages and cost prompt Municipalities and Shires to seek underground for water for public purposes. Borehole pumps provide the means to tap the 97 per cent of water resources found underground.

The Mono borehol e pump is versati le, can be driven by any met hod ava il abl e, has co ntroll ed output s to suit all bore capacities and high head capabilities. The range of 19 Mono pumps ca n handle th e most difficu lt silt laden, hard or brackish waters up to 240 m deep . Enqui ries: Mr D. Dawson, Aust. Marketing Manager, Mono Pumps (Aust.) P/L, P.O. Box 123 Mordialloc 3195

WORMALD STAFF MOVES Wormald Machinery Division of Wormald International has announced formation of a Valve Group under the direction of Operations Director, Mr. J. D. Bonthorne. The Group com bin es the resources of John Valves , James Kemp , Gordon Marr and Ri c hard Val ves & Controls. Mr. Bonthorne anno un ced the foll ow ing appo intm ent s f or th e Valve Group Mr. B. A. Richard s as Div ision al Manag er, Geebung Works (Bcisba ne), Mr. H. E. Beiers as Divis ional Manager, Currumbin Wo rks , Mr. R. J. John as Market Deve lop ment Manager and Mr. T. P. Kee ling as General Sales Manager. A single sa les force has been c reated for the Valve Group w ith a Nation al Sales Offi ce at 22 Cato Street , Hawt horn East 3123. Vi c. and Regiona l Sales Offices aro und Au stralia. Mr. Kee lin g anno un ced th e app o intments of the fo ll owing Reg ion al Sa les Managers-Valve Group. J. A. Aitken for Qu eens land and North ern Territory based in Brisban e, C. Mickleburgh for Vi ctoria, South Australia and Tas mania based in Melbourne, W. A. Shelton for New South Wal es based in Sydney and R. A. K. Palme for Wes tern Austra li a based in Pert h. Market Managers have been appointed as fo ll ows : K. Finley-Water Di stribution ; C. Marshall -S tandad Products; F. J. Outram- Ri c hard s Produ ct s and T. Spence-Power Generation . An ad diti o n to the staff is Mr. Ray Smith recently of Wes tinghou se Brake and Signal Security Sys tems who is no w Manager John Products, locat ed at â&#x20AC;˘ Bal larat. Mr Roger Mansell has been appointed Divisional Manager-Ballarat Work s

FRINGS AUSTRALIA STAFF Fri ngs Australia, agents for Henri c h Frings GmbH . & Co. KG . of West Germany, announce the appointment of Mr. Richard Mason as Project Engineer. Du e to th e very high leve l of success obtained by Frings with Immers ible Aerators for wastewater and sewage treatments , it has beco me necessary to appoint a Projec t Engineer to s upport the Environment Engineer Manag er, Mr. Toni Fitzgerald , in the market ing and installation of thi s equipment. Rich ard Mason has had cons iderable experi ence in the des ign and marketing of aeration equ ipm ent , pumps, etc. and will provide his ex peri ence in th ese areas to Frin gs to help ensure that th e c urrent , very high growth rate is maintained.

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EUWA (Aust.) Pty. Ltd. , a newcom er to Australia will be exhibitinlJ at AWWA 's Sydney Convent ion . This entirely new electro-chemical demineralising system combines electrodialysis and electrophoresis in a revolutionary ion exchanger re-generated electrically. Requires no chemicals , re-generat ion system , neutralising equipment or expensive pre-treatme nt. EUWA also manufacture conventiona l plants for ion exchange, pH contro l, degasifying , oxidation , steril ising and disinfecting liquids. Further information , see advertisement page 4.

A new transmitter option with Kent Rotary Shunt meters makes possible remote reading and flow rate recording Type RS/C. Totalisat ion of steam f lows (suitable for the measurement of vio lently fluctuating flows) . Type RW/C. Totalisat ion of water f lows (e.g. for the measurement of bo iler feed and condensate returns). Type RA/C. Totali satio n of flow of c lean air, methane, argon , nitrogen , hydrogen and other gases.

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Acromet metering pumps have application in the food , process, mining , municipal and petrochemical industries. The wide ra nge of materials avai lab le for wetted part s makes the 'Acromet 900 ' extreme ly versat il e, as we ll as being both an accurat e and rugged performer. For information: Acromet (Aust.) P/L, P.O. Box 491, Clayton 3168.

KENT VERIFLUX MAGNETIC FLOWMETERS Th e new range of d.c. pulse and a.c. f lux sensing magnetic meters are now in fu ll prod uction in Austra lia. The meters are ava ilab le in 12 mm to 750 mm nominal bore with a wide se lect ion of lining and of electrode materials and are supp lied with NATA calibration certificates . Enquiries : Douglas Rickland, Marketing Manager, Kent Instruments (Aust.) P/L, 40 Box Road, Caringbah 2229

E. A. Stanson & Coy Pty Ltd The 1982 edition of this catalogue is now available . The instrument range covered inc ludes : • Dissolved oxygen meters • Salinity and conduct ivity meters • Waste water samplers • Ope n channe l f lowmeters • Spectrop hotomet ers • Fluorometers • Nephe lometers • TLC/FID analyser • CO2 incubators • ATP photometer and reagents • pH meter • Co unting ce lls For free copy write: A. E. Stansen & Coy P/L, P.O. Box 118, Mount Waverley 3149. Phone (03) 544 8022.

WORMALD CAPABILITY BROCHURE The Machinery Group of Wormald Machinery now makes available a capability brochure, in colour, giving an overview of the various operating companies facilities and principal products, made in Australia.

The Wormald Mac hinery companies in Australia are formed into two operating groups as follows , Pump Group with Kel ly & Lewis Pumps, KL Giles & Gaskin Pumps , KL Worthington Pumps and Kelly & Lew is Machinery. The Valve Group comprises John Valves including Kemp and Marr Prod ucts and Richards Valves & Contro ls. The brochure also gives details of the company's complete capabi lity in the des ign, contracting and appl ication of pump , valve and allied equipment for the transport and contro l of fluids. Write to Group Communications Dept., Wormald Machinery, P.O. Box 160, Springvale, Vic. 31471 .

Kent Rotary Shunt Meters are avai lable for direct in-line mounting in 50 mm , 75 mm and 100 mm piplelines or for by-pass mounting across an orifice plate in pipelines up to 600 mm diameter. For information: Douglas J. Rickard, Kent lnstrument.s Australia P/L, 70 Box Rd., Caringbab 2229.

DROUGHT DEFENCE Look down for water as well as to the skies. In suitable locations, Wellpolnts are providing a welcome augmentation to surface water supplies. In the mid north-west of N.S.W., Vortec Industries have been successful In applying 'de-watering' techniques for water supply purposes. The system of Gulgong has be nefited from We llpoint instal lat ion and Mudgee and other centres are fol lowing along similar lines with points or we ll s. Further information: Mr. R. Gray, Vortec Industries P/L, 62 Mandoon Rd., Girraween, N.S.W. 2145. W A T ER D ecember, 1982 25

•

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Capital Controls hopes you never have to use yours.

RIVER SANDS PTY. LTD.

High Quality If yo u work with chlorine gas, you do not need to be told how dangerous it can be. But you should be warned of its presence long before it becomes a hazard - to personnel and equipment. Yo ur nose is dependable. Our ADVANCE Series 103 0 c hlorin e gas detector is more dependable. In fact, all of its features many of them exclusive - combine to make it the safest and the most reliable in th e industry . The Series 103 0 's dual monitorin g capabi lity is one such exclusive . Separate alarm and warnin g circuits provide backup alert in th e event of either slow gas accumulation or a major chlorine leak. Perhaps we should say in any event, because the Series 1030 is the only gas detector that is se ismically and radiation qualified . Other credentials include a totally solid -state design (no chemicals required). a fail-safe operating mode, radio freq uency interference (RFI) protection, and output alarm contacts. We have built our gas detector for quick response to extremely low chlorine levels . It is field adjustable in the alarm mode from O to ~ 1 O parts per million chlorine . Li ke most systems, the Series 1030 uses a remote se nsor that mounts at the detection poin t. But unlike most, it permits separation of up to 1000 meters between sensor and electronics. For safety, a reliable chlorin e gas detector is a must. And for reliability , the ADVANCE Series 1 0 3 0 is the best. Lt is as simple as that. Call or write us for a free product bulletin.

ADVANCE ... at your service.

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A CAOME T ( AU S T.) P TY. L T O .

FILTER MEDIA Manufacturers at REDLAND BAY ROAD CARBROOK, Q. 4130 07-2098344

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NOTIFY ADDRESS CHANGES TO YOUR BRANCH SECRETARY OR THE EDITOR

VICTOR IA: 14 Winterton Rd ., Clayton . 3 168. Telephone: (03) 5 44 7333. Telex: AA 3 0 9 18 N.S.W. : 19 Gibbes St. . Chatswood , 2067 . Telephone: (02 ) 4 07 02 01 Telex : AA 225 86 ACR1 5

28 WATER December, 1982 Primed by Exchange Press, Brunswick 03 380 8 I94

SEWAGE ODOR CONTROL with ACTIVATED CARBON SIMPLE

RELIABLE

V ECONOMICAL

The AQUA-WRIGHT SOC units are specially designed for sewage odour control. Utilising GRANULAR ACTIVATED t CARBON they have proven completely effective in elim inating citizen odour complaints. Consu ltants and Authorities recognise AQUA-WRIGHT Sewage Odour Control Units as the most effective means to remove sewage odours. Already more than 30 of these units are in operation throughout Australia, giving simple, reliable, economical service. Hydrogen Sulphide and odour causing organics are removed by passing the odorous airstream through a bed of act ivated carbon. Purified air is vented to the atmosphere. AQUA-WRIGHT S.O.C. units are effective for high, low or varying concentrations of odorants, in large or small airflows. Our systems are based on improved activated carbon technology to give you a more efficient and economic approach to sewage treatment plant odour control. Complete packaged adsorption units are availab le in flows from 25 to 3000 litres/second. The units are built w ith corros ion resistant materials and are eng ineered so that noise and maintenance are minimised. The on ly moving part is the blower/motor assemb ly. For SIMPLICITY, RELIABILITY & ECONOMY in sewage odour control , write or telephone us today.

AQUA-WRIGHT A division of Wright and Company Pty. Ltd. Head-office 32-40 Maddox St . , Alexandria, NSW 2015, Tel. 51-3371, Telex 24237 Branches in Brisbane, Melbourne, Adelaide, Perth

For Resource Recovery and Pollution Control there's just one name to remember...

EIMCO Thickeners - Centre Drive/Column Type

EIMCO Belt Filter

There are a lot of important names in the fields of resource recovery and pollution con trol - names like EIMCO, WEMCO, Shriver, Goslin, Carrousel<", BSP and ASH. But one name - Envirotech - covers them all. Together with broad engineering design and manufacturing skills, Envirotech offers the continually up-dated technology of acknowledged world leaders. When you need equipment for. .. Flotation Heavy Media Separation Thickening & Clarification Vacuum, Gravity & Pressure Filtration Sewage Treatment ... there's only one name to remember.

WEMCO H.M. Separation Drum

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Envirotech Australia Pty. Ltd. A Company in the Engineering Division of Mitchell Cotts Carruusel Sewerage Treatment Plant

Syd n ey

Perth

102) 449 4222

109) 321 4541

Telex: AA2 l 775