Water Journal September 1980 by australianwater

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0310 - 0367

Official Journal of the AUSTRALIAN WATER AND

l\~ii=VMi=l;6i-i•XeJrtiit•1~1

I Vol. 7, No. 3, September, 1980 Registered tor posting as a periodical -

Category 'B'.

$1.00

EDITORIAL

Chairman, C. D. Parker F. R. Bishop Mary Drikas E. A. Swinton T. M. Smyth B. S. Sanders Joan Powling T. Fricke W. Nicholson J. H. Greer W. E. Padarin B. J. Murphy P.R. Hughes H. Wilson J. Bales Editor: Publisher: G. R. Goffin A.W.W.A. BRANCH CORRESPONDENTS

CANBERRA A.C.T. To be announced.

CONTENTS Viewpoint ... . . .... . .. . .. . . .. ... .... . . .. .. .. .. .... . . .

Association News ... . .. . ... .. ... . . .... . . ....... . . . . . . .

IAWPR News . ..... . . . .. . ............ . .. . . . .. . . ...... .

Mercury in Aquatic Environments - A General Review - L.A. Nagy and B. H. Olson .. .. . ... . . . ... .. . . .. ... .

The Philosophy of Australian Water Legislation - Part 1 - Sandford D. Clark . . . ... .. . . .. ... ..... .. ........ .

SOUTH AUSTRALIA Mrs. M. Drikas, State Water Laboratories E. & W. S. Private Mail Bag Salisbury 5108. 08-258-1066

Sirofloc - A New Water Clarification Technique - A. J. Priestley and P. R. Nadebaum

Toxicity of Wastewaters - Some Practical Implications - W. D. Williams ....................... . ... . .. . .. .

WESTERN AUSTRALIA C. M. Tucak, 18 Ventor Ave., W. Perth 6005 09-321-2421

Water Quality Management of Storage Reservoirs - W. D. Lynch ........... . .... ..... .. . .., . ... ... .. .

TASMANIA

Conferences and Comments .. . .... . ... . .. . .......... .. .

NEW SOUTH WALES T. M. Smyth, G. H. & D. Pty. Ltd., P.0. Box 219, Neutral Bay Junction, 2089. 02·908-2399 VICTORIA J. Bales, E.P.A., 240 Victoria Parade, East Melbourne, 3002. 03,651-4685 QUEENSLAND P. R. Hughes, P.O. Box 276, lndooroopilly, 4068.

R. Camm, Cl· Met. Water Board, Macquarie St., Hobart. 002-30·2330 NORTHERN TERRITORY H. Wilson, Water Div. Dept. of Transport & Works, P.O. Box 2520, Darwin NT 5794. 089-81-2450 EDITORIAL & SUBSCRIPTION CORRESPONDENCE G. R. Goffin, 7 Mossman Dr., Eaglemont 3084, 03-459-4346 ADVERTISING Mrs. L. Geal, Appita, 191 Royal Pde., Parkville 3052. 03-347-2377

WATER

PAPERS REQUIRED FOR 'WATER' Members and others are invited to submit artic les or proposa ls for such for publication in this journal. Articles should be of original thought or reports on original work of interest to fhe members of the A.W.W.A. In the range of 1000 to 5000 words and accompanied by re levant diagrams or photographs. Full instructions are available from Branch Correspondents or the Editor. CSIRO style Guide will assist.

COVER STORY " Victoria has established at Werribee, a Centre for training of operators of water and wastewater plants. Capital costs of the Centre were provided as part of a joint Commonwealth -State program. ,The Centre is managed by a Committee established by the Victorian Water Resources Council and is developing a range of courses appropriate to its needs for water and wastewater treatment. These courses are available to applicants from the Commonwealth and other States . The photo shows a training session in progress."

Have you a sulfide odour or corrosion problem? Have you considered ·hydrogen peroxide? When you've got a sulfide odour or corrosion problem you want a complete, reliable solution notjust a'cover up~ And you want it to be simple. A solution that freshens septic sewage, thereby improving treatment plant performance. Preferably this system should be non-polluting. After all-removing pollutants is your business. You, also, want ready technical back-up and on-site assistance. . You've just specified the ideal answer to your problem, the solution you thought couldn't exist. Ask us about lnterox hydrogen peroxide .

•

I Hydrogen peroxide.The natural solution. INTEROX CHEMICALS PTY LTD. NEW SOUTH WALES. 20-22 McPHERSON STREET, BANKSMEADOW, NSW 2019. PO BOX 18, BOTANY, NSW 2019. TELEX 20628. CABLE PEROXIDE SYDNEY NSW. TELEPHONE 6668000. VICTORIA. 480 SOMMERVILLE ROAD, WEST FOOTSCRAY, VICTORIA 3012. TELEX 33512 . TELEPHONE 3146899. QUEENSLAND. HEDLY AVENUE, HENDRA, QUEENSLAND 4011 . PO BOX 502, HAMILTON CENTRAL, QUEENSLAND 4007 . CABLE PEROXIDE BRISBANE QUEENSLAND TELEPHONE 2686000. SOUTH AUSTRALIA. 195 GRENFELL STREET, ADELAIDE, SA 5000. CABLE PEROXIDE ADELAIDE SA. TELEPHONE 2234046. WESTERN AUSTRALIA. 643 MURRAY STREET, PERTH, WA 6000. TELEX 92490. TELEPHONE 322 5991 . NEW ZEALAND. BUCKLEY & YOUNG LIMITED. 17-21 MAIDSTONE STREET, GREY LYNN, AUCKLAND NZ. TELEX 742546. TELEPHONE 762127. LAP4037

WATER

• For expertise in difficult applications

• compression plant• blowers •valves

Donkin provide conventionally lubricated reciprocating compressors, or oil free units suitable for applications where no trace of oil must mix with working gases. Single and multi~stage centrifugal units are also,available. Working up to 48 MPa gauge, Donkin compressors can be particularly suitable for 'difficult' gases such as coal and natural gas, petroleum refinery process products, ammonia and carbon dioxide.

Donkin supply rotary blowers, boosters and exhausters - either centrifugal or the simple and robust Roots type. Major uses include smelter gas exhausting, fuel gas boosting, sulphur dioxide handling in acid plants, materials handling and providing air for sewage treatment. These low-pressure machines are available for high volumes - up to 170,000 cubic metres per hour.

The Donkin valwe range includes gate, butterfly and non-return valves for the control of fuel gas mains, air, coke oven hot gases, corrosive sulphurous gases, or process gases in industry. Units are available from 600 to 1200 mm, even to 1800 mm pipe bore size.

Donkin products, associated with the gas industry for 150 years, are utilised in gas compression and control for process engineering, industrial gas supply and pneumatic conveying in every part of the world .

~ Hawker Siddeley Engineering Pty. Limited Incorporated in NSW

Head office : 262-284 Heidelberg Road, Fairfield Vic. 3078. Tel : 489 2511 Branches: Sydney, Brisbane, Perth. Hawker Siddeley Group supplies electrical and mechanical equipment with world-wide sales and service.

3397HSE

WATER

METERING PUMPS

~THE BETTER BUY -

EVENTUALLY CHEAPER'

YOUR CHECKLIST TO RELIABILITY AND ACCURACY

•

Robust cast-iron gearbox. •

Totally enclosed mechanism. •

Hardened & ground wormdrive. •

Heavy duty bronze gears. •

Oil bath lubrication and oil flow inducer. •

The unique 'Acromet' balanced reciorocatina mechanism. - Eliminates gear backlash. - Reduces wear in gears and bearings. - Incorporates automatic wear compensation to maintain accuracy in stroke length. •

'Acromet' microlinear adjustment - Fine adjustability - manual, pneumatic, electric . - Large easily read scale 100 clear graduations - All protected from corrosion and damage under glass lens and hinged metal cover.

•

THE WAYI

Capacity adjustment by both length and duration of stroke and minimum head capacity at any setting . For positive valve action & accuracy. - For best purging of solids & entrapped gases. •

Double diaphragm or plunger type pump head. •

FOR QUALITY

Double valves on suction and discharge.

EQUIPMENT AND SERVICE 80 head size and speed combinations to give the capacity and pressure rating required.

BE ASSURED

NOMINATE YOUR SUPPLIER SIX models to choose from you can have a very robust, simple and inexpensive pump for the less demanding service.

'ACROMET' CHEMICAL FEEDERS ACRISON - Dry materials feeders ACROMET - Metering pumps ADVANCE - Chlorination equipment

PUMPS NIKKISO -Glandless centrifugal and metering SUNOYNE Single stage high head also SUNFLO - compressors and blowers VANTON -Plastic glandless , centrifugal and sump JUNG -Submersible drainage and sewage

METERS VALVES BRUNER -Filter and softener controllers KATES -Automatic flow rate controllers MUESCO -Automatic valves for level and pressure PLAST-O-MATIC -Plastic valves electric and pneumatic

ERDCO -Variable area liquid and gas BALL -Vortex totalising KEENE -Positive displacement MUESCO-Propellor meters tor water supply and irrigation PODDY -Acrylic manometers and flow meters CHLORSCALE-Ch lorine c yli nder scales

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WATER

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QUEENSLAND (07) 44-7044 SOUTH AUSTRALIA (08) 46-6847 WEST AUSTRALIA (09) 381-4477

1. The DeZURIK® V-Port Ball Valve A rugged and unique control valve that comb ines high capacity and lo w cost. Offers precision control for a variety of applications to 740 psi with temperature ratings to 1000 °F. Sizes ½" -20". 2. The DeZURIK PERMASEAL® Plug Valve This simple, tough valve features a self-adjusting plug that compensates for wear and temperature changes, plus " true top entry" for in-line maintenance . Bi-directional shutoff to 1480 psi. ANSI 150, 300and 600 in sizes ½" -6 ". 3. The DeZURIK C Series Knife Gate A proven performer in the toughest abrasive and corrosive services. Available with lever, handwheel , electric motor, on -off or positioning cylinder actuators . Sizes 2"-72".

4. The DeZURIK FIG 660 RS Butterfly Valve A unique seat design ensures bi· directional shutoff to 150 psi and a streamlined disc delivers high flow capacity . Choice of seat materials, actuators and wafer or lug in sizes 2"-12". 5. The DeZURIK FIG 632 RS Butterfly Valve The resilient seated butterfly valve that offers unequalled performance and an exclusive double-seat in sizes 2" -20". Wide choice of actuators. Choice of wafer or lug body in al l sizes : 2"-36". 6. The DeZURIK HP Butterfly Valve A high performance valve that features an exclusive TFE/titanium seat design to assure a lasting, bubble-tight shutoff. Excel lent corrosion resistance and temperature accommodat ion in

si zes 2" -20 " . ANSI 150 and 300 to 740 psi . 7. The DeZURIK Eccentric Valve 28 sizes and a hoi t of options assure the exact combination for any application. Eccentric action delivers a lasting dead-tight shutoff in si zes from ½"-72" . 8. The DeZURIK 3-Way & 4-Way Valves Rugged performance for virtually any shutoff or switching application . Lever, handwheel , onoff or positioning cylinder available in sizes 3" -16 " . 9. The DeZURIK Rotating Sensor Consistency Transmitter Electronic or pneumatic contro l assures unmatched sensing accuracy. Unique involute ribs are influenced only by stock consistency.

A UNrr OF GENERAL SIGNAL

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WA T ER

!AUSTRALIAN WATER AND!

VIEWPOINT

!WASTEWATER ASSOC IATION!

FEDERAL PRESIDENT A. Pettigrew, P.O. Box 94, Rocklea, 4106. FEDERAL SECRETARY P. Hughes, Box A232 P.O . Sydney South, 2000. FEDERAL TREASURER J. H. Greer, Cl- M.M.B.W . , 625 Lt. Collins St., Melbourne, 3000. BRANCH SECRETARIES Canberra, A.C.T. D. Coucouvinis, C/- River Murray Commission, .P.O. Box 409, Canberra City, 2601. (480-177) New South Wales R. M. Lehman, Sinclair Knight & Partners, 2 Chan dos St., St. Leonards, 2065. (439-2866) Victoria R. Povey, S.R.W.S.C., Operator Training Centre, P.O. Box 409, Werribee, 3030. (741-4171) Queensland J . Ryan, C/- Gutteridge Haskins and Davey, G.P.O. Box 668K, Brisbane, 4001. (221-7955) South Australia A. Glatz, State Water Laboratories, E. & W.S . Private Mail Bag, Salisbury, 5108. (258-1066) Western Australia C. M. Tucak, 18 Ventnor Ave., West Perth, 6005. (321-2421) Tasmania p. E. Spratt, C/- Fowler, England & Newton, 132 Davey St., Hobart, 7000. (237-591) Northern Territory K. Sajdeh, Water Div. Dept . of Transport & Works, P.O. Box 2520, Darwin, N.T. 5794. (895-511) WATER

WATER MANAGEMENT -~HE FUTURE

Water managers have been concerned with and must increasingly consider the integration of demands on the water resource (in its broadest term) with all facets of society's needs and objectives. Victoria has a complex _allocation of functions relating to the use and control of its water resources. There are issues emerging which are forcing a re-examination of these institutional arrangements. Over recent years, studies related to wastewater management in both the Yarra Valley and Westernport catchment, water supply in Gippsland including particularly the Latrobe Valley and, more recently, the establishment of "sunset Legislation" (Public Bodies Review Committee) raised questions which should concern all those involved in water management. Increasing public debate on 'big' versus 'little' government and the questioning 9f government at all levels, leads to the need to define what is The function of government in relation to resource development. It would be generally accepted that the State has four broad objectives:• • • •

Increase of income to achieve self-sufficiency Re-distribution of consumption Preservation of the quality of the environment Retention of historical, cultural and scenic values

It would, I think be accepted that these objectives apply not only to the State as a whole, but also to the Nation, and to regional and local areas. The community, temporary residents of these areas as we are, has developed increasingly complex water and related land resource systems - systems in which public intervention in the form of investment, regulation and management are necessary. As water managers, the responsible Authorities have always been concerned with hydrological unity and the consequences flowing from decisions or activities which affect land use. In recognising (accepting?) that any government must be free to combine or separate the planning of its land and water resources based on its concepts of the necessary divisions of governmental power, we also acknowledge that our duty is to define the influences affecting the use of our natural resources, to integrate these with the planning process, to provide advice professionally, and to resolve conflicting interests and seek consensus on community values . Th ere are clear indications in a number of regions in Victoria that we are approaching limit s to the use and development of our water resources. This will pose new challenges for management, challenges to be met by the use of a much wider range of measures than have hitherto been applied . Considera~on of the use of these measures will inevitably lead to a questioning of our economic and socia l valu es and ma y significantly influence quality of life issues. Regardless of the wa y a government divides its function s institutionally, management of the water resource will alwa ys be essential, it will become increasingly more complex and will involve a wider range of disciplines th a n those which have traditionally been involved in the past. John N. Mann Director of Wat er Resources , Victoria Ch airm an, Water Resources Counci l, Victoria

A.W.W.A. MEMBERSHIP Requests for Application Forms for Membership of the Association

should be addressed to the appropriate Branch Secretary. Membership is in fo ur categories: Member-qualifications suitable for membership in the Inst . of Engineers, or other suitable professional bodies. ($15 p.a.)* 2. Associate-experience in the W.&W.W. Indu stry, with formal qualifications. ($15 p.a.)* 3. Student. ($5 p.a.) 4. Sustaining Member-an organisation involved in the W.&W.W. Indu stry wishing to sustain the Association. ($65 p.a.) *P lu s State levy where app li cable. 1.

ASSOCIATION NEWS PRESIDENT'S COMMENT CONFERENCES - THEIR POSITIVE VALUE

I am pleased to advise all memb ers that the Australian Water Co-ordina ting Committee, initiated by A.W. W.A ., continu es to gain impetu s. In addition to the establ ished valu ed participants we were pleased to welcome th e interest of th e Water Research Foundation and th e Water Resources Co uncil at our meeting in Sydney recently. On e of the ma in topics for di sc uss ion was th a t of Co n ferences. By the time th is issue goes to print, I hope to be in U.S.A. where it will be my privi lege to represent this Association at the Annual Conference of th e Water Po llution Control Federation in Las Vegas. this in vitat ion was iss ued by Geoff Sco tt during his visit to our 8th Federal Convent ion last November when our two Associations moved closer in their id eas and co-operati ve efforts. Th e value of co nferences is enormous much beyond the presentation of th e papers, or even the for ma l discussions of them. The capac it y of people of like interests (or sometimes of op pos ing ones) to express their views, and to li sten to other ideas and developm ent s is imm easurabl e. Of equal import ance is the opportunity created for peo pl e to make ac tive and persona l contacts within the framework of the indust ry, to become more than just a signature or a name on a newsletter, or a committee memb er who we never see. This is vital to the progress of any organisation. Th e int erchange of id eas goes far beyond th e sub stance of th e formal gath erings. Th e Federal cou ncil has of recent years been pressing for closer co-operation between organi sat ions, and we are happy to report that with in this fr a mework we envisage com bin ed conferences in the near futur e, with th e active and enthusiastic support of two or more of o ur affiliated organisation s. This can be of cons id era ble benefit on a regional level (e .g. regional Pacific Area Conferences) keeping in mind the escalating cost of International travel. Nearer to home, the Perth Conference shows signs of being one of the best yet mounted by thi s Ass ociation. The Organising Co mmittee at thi s stage have reason to be pleased with progress, but the vita l ingredient is still to come - PEOPLE. The meeting of minds for technical discussion , and for the furtherance of the AWWA, together with the practical ass istance from such bodies as In stitution of Engineers Aust.

as Secretariat, the increasing multi disciplinary aspect of the Association - all this combined with the hospita lity of our friends in Western Australia will MAKE PERTH A GOOD PLACE TO BE IN APRIL '81. ALLAN P ETTIGREW

NORTHERN TERRITORY Memb ers of th e Branch joined members of the Institution of E ngineers in a joint meeting arra nged by the In stituti on on July 3rd. Mr. Jeff Bowden of th e Queensland Branch of Kent In struments (Australia) gave a most in teresting talk on the Company's speciality flo w measu rement, ranging from domestic water supply meters through to large volum e meas urement in pipelines including magnetic flow dev ices. Local interes t in the talk was enhanced by a recent survey by the Operations Section of Water Division in conjuncti on with Kent, of flow measurem ent requirements at severa l sewage treatment installation in the T erritory. At a lunch-tim e meeting on August 14th , Mr. P eter Chap man, at ional Techn ica l Sales a nd Development Director of Vinidex Tubemakers P / L gave the Bra nch a lecture on the technical aspec ts of PV C piping and its usage for water and sewage tran sportation. Th e spea ker covered the behaviour of UPVC pipes under va rious conditions encountered in service , the stress and flexure performance and characteristics and illustrated his comments with slides. In the evening of the 14th , a t the Branch AGM, Hugh Wilso n was elected President with John Paul as Vice President; Secretary for the coming year is Kewel Sajdeh a nd Treas urer Ron Frey ling. Committee memb ers are: Bob Morrison, Dr. John Quinn, Robert Lloy d, Con Mappas, Rod J ackson, Col. Brown, Percy Wij enake and Alex Kotrancz. Hi~h Wilson also continues to serve as Bra nch Correspond ent for ' Wat er'. To round off the evening, Robert Lloyd, now P ast Preside nt gave a ta lk on his rece nt visit to Canada where he attended the IAWPR Conference in Toronto. The Branch is enthusiastic abo~t the recent sugges tion from th e Editorial Comm ittee that the scope of Association News should be in creased to includ e comment in State Activities in the field s of interest to A WW A memb ers and wi ll be anxious to spread th e story of activity in the Territory.

TASMANIA Since the last report the Branch has had a quiet time and a dearth of material for meetings . This problem is endemic with smaller and accordingly more iso lated Branches and the practica l solution is improved input from th e more populous States . Visitors can be picked up 'on th e wing' if there is pre-know ledge of the visit, assuming of course the visitor is prepared or will give an ad- hoc prese nta tion , but this approach is over uncertain . Federal resources could prob a bly assist by offer ing some co-o rdination and assistance

with visits which would bring tangible benefits to th e areas of fewe r resources. (Editor)

Th e Annual General Meeting will be held on September 29th when Mr. J. R. Ashton, Co mmi ssioner of th e H.E.C. will be talking to the Branch. Mr. Ashton will have just returned from an overseas visit which shou ld provide plenty of interest fo r the meeting.

WESTERN AUSTRALIA Branch Activities

Branch activities have been very much concentrated on preparations for the 1981 Confe rence which promises to be one of the Associations mo st successful - see the notice on page 29. The AGM will be held on September 4th and results will be available as this issue goes to press. The meeting will be given an illustrated talk by Mr . T. H . Lawson of E nvirotech on "Oxidatio n Ditch Design". Membership applicatio:1 is increasing, a source of satisfa ction to all concerned. State News Cadoux Reservior Earthquake Damage

On June 2nd, 1979 a severe earthquake damaged the small town of Cadou x approxima tely 2I5km north east from Perth. Approximately 4km north of the town is a standa rd reinforced concrete water storage of 900 m 3 capacity built in 1960 and located on top of a local rise. The reservoir is 46 metres internal diama ter with walls 5.5 metres high, 380mm thick at the bottom stepping in on the outside to 190mm at the top. The wall contains approximately 230 cubic metres of concrete and was joined to the 300mm tltick base slab with a dumbbell water sea l. The reservoir is supplied by a 300mm M.S.C.L. above ground m ain from the south west and has a 300mm M.S.C. L. outle• to the north east. On the day of the earthquake the reservoir was in operation and full of water. The quake caused the following damage: • The inlet pipe fractured at a field joint and separated by approximately 230mm. • The outlet pipe compressed at a field joint. • The reservoir ring (wa ll) was bodily mov ed a long the 348 ° bearing over the slab for • 430mm, tearing the seal between the wall and floor and releasing all of the contained water. The outside edge of the ring now slightly overhangs the edge of the base slab at one end of the 'bearing' and the 'shadow' of the base of the wall and slab are completely exposed at the other end . • There were some 7 fractures in the I 00 a nd 58mm A .C. water reticulation main s within Cadoux townsite. Repairs to the reservoir with th e wall in its new position consist of an internal Bituthene bandage between wall and original floor slab. The reservoir was repaired in time to be used for the 1979-80 summer demand period and is still in operation. The organising Committee for the forthcoming Conference hope s to have a WATER

photographic exhibition of the damage at th e Co nference. Any interested in visiting the site on th e weekend before the 198 1 Conference should contact th e Branch Correspondent to allow him to ass ess numbers etc. and the possibility of a visit. ·

M. W.S.S.D. Board Penh - Big Move After ma ny years of sha rin g a building with the Public Wo rks Depart ment in West Perth a nd of spreading it s over fl ow into 5 ot her buildings in th e West P erth area the M.W.S.S.D. Boa rd wi ll, o n Se pt em ber 12th gather its workforce of some 950 persons a nd move int o its own new building, to be referred to as the 'Water Centre' in the adjacent suburb of Leeder ville. The building of three floor s of offices with undercover pa rkin g is surround ed with plan ned landscape ga rd ens designed to minimi se noi se interferenc e from the adjace nt freeway. The site was for merl y occupi ed by the Bulk Stores and a Maintenance Depot. St ill remain ing on the site, in co ntinuo us opera tion , a nd located within the land scaped a rea is the Board 's No. l (yes, o ld faithfu l it self) Wastewater Pumpin g Station. The o utside of the Co ntrol Building has received a face li ft by claddin g as used on th e new building. A C .S. l.R .O . Sirot herm pil ot pla nt is a lso incorporated in th e new deve lopment to desalin ate water fl ow from artesia n bo res on the site. The treated water will be pumped to the ex isting Mt. Eli za sto rage reservo ir in Kings Park. A separate plant room has a bank of so lar heaters for air conditi oning and th e main building has been designed as a n energy efficie nt ce ntre with tinted glass and o verh anging upp er flo o rs. The building will have a comp uter cen tre on the top floor and coin operated beverage vend ing machin es o n each fl oor which may herald a nd end to t he tradition al P.S. tea break by providing a selecti o n of fo ur hot beverages at all tim es . Th e build ing has facilities to provide up to 20 conference room s by use of fo ld-away wa ll s. In the old building a roo m was alw ays kindl y made avai lable to the A.W.W.A. Branc h Co mmitt ee fo r it s periodical meetings. We look fo rwa rd to the sa me kindness in the new ce ntre. The move wi ll be completed in time to open for bu siness o n Monday, Se ptem ber 22nd. Unfortunately dela ys in equipme nt will result in the existing telepho ne number being reta ined for a short period until the new number is known. Th e M. W. S.S. D. Board a nd it s officers are a la rge part of AW WA - W.A. Bra nch . Inspections of the Board's in stall ations have always been readily ava ilable a nd ma ny of the staff who are A WW A memb ers contribut e both wit h pa pers a nd to th e running of Bra nc h affairs. The remaining members of W.A . Branch wi sh th e Board we ll in its move and sa ti sfaction wit h their new surroundin gs.

QUEENSLAND Over sixty atte nd ed the Branch meet ing on Jul y 16th to hear Mr. Keith Strick la nd of Enviroshi eld Di vision o f C. l. G. Brisbane give a review of his exper imental work on the use WATER

of ox yge n in the treatment of wastewater and for odour control. ln his most interestin g talk, Mr. Stri ckland drew u pon his experiences in Zambi a a nd Kenya and used co lour slid es for illu strati<;m. The next Branch meeting on June 25th wa s attended by som e 80 members to hear Mr. Mik e Wilkie of th e Water Re sources Commiss ion talk on hi s ex periences in Abu Dhabi with the construction of a wastewater treatment pl a nt, pumpin g a nd pipeli nes . Mike was engaged upon th e wo rk as a Co nfederat io n of British Indu stries Schol arshi p winner attached to an English con sulting organisation. At thi s meeting a nd also the June meet ing, Certificates of Complet ion were issued to Plant Operators of Sewage, Water Suppl y a nd Swimming Poo l pl a nt s. Geoff Cossin s, a Past Pres id ent presented th e ce rtificates and also awards to the highest gradua tin g stud e nt s in the th ree disciplin es fo r the I 978 and 1979 cou rses. Augu st saw a new meeting ve nue for the Bra nch , the ew York Hotel in Brisba ne. Here the AG M was held on th e 27 th and was we ll attended in pleasing surroundings. After the usua l formaliti es , retiring President All a n Pett igrew provided a n illustra ted talk o n 'Closed Systems for Water Reuse in Abbattoirs' wh ich was colo ur fu l in every sense of the word. The Bra nch' s nex t acti vity, scheduled for th e time when thi s Journal is go ing to Press , is a Work shop/ Se min ar on Se ptember 12th on ' Des ign Frontiers in Water and Wastewater Treatment '. Subjects for thesession incl ude : viru s re mo va l, nutri ent removal, non -point so urces of pollution, indu stri al waste trea tm ent and urb a n drainage water qualit y. Pan el discuss ions are progra m med for Lake and Water Stor age Management and Wastewa ter Reuse . Our next issue wi ll carry a report of th e days activities. The lin e-up of speakers is im press ive and a goo d a ttenda nce should ensue. The Bra nch Co mmittee had had an active yea r a nd has co mpl eted prelimin ary proposa ls fo r: altera tion s to the Branch By-law s , recommended cha nges to th e A WW A ' Rul es' , me mb er s h ip s e r v ice s . Pl a nt Operators Certificate Fund, Life Membership proposals, Reg ional Co mmittee formation a nd Branch Newsletter format. Th e Committee for the coming yea r will consist of: President - Brian Rigdon ; Vice Presid ent , Peter Hu ghes (continues as Co rrespondent for Water); Secretary, John Rya n; Trea sur e r, No rm Whyte; Asst. Tr eas ur e r , Juli e Ive son; Membership Secre tar y, Cli ve Norton; Progra mmes, Robin Black; Social , Nevi lle Jones; Committee Humphrey Des mo nd , Murray Allen, Lou Jone s, Jack O'Connor, Leo Roessler, Bill So ll ey a nd Keith Stric kland . Allan Pettigrew is Past-President. The outgoing Co mmitt ee wishes to acknow ledge th e wo rk done by prev iou s Com mittee memb e rs Mrs. Marg Pettigrew fo r her work on the Comm ittee over th e past years a nd also her exte nsive work undertaken in the o rgani sa ti o n of the 8th Federal Conventi o n last Nove mb er. The Co mmittee a lso wishes to thank me mbers who nominated for position s on the 1980-8 1 committee but who were unsuccessful in the ballot.

The Q ueenslan d Branch Co mmittee wou ld be pleased to hear fro m any Regio nal Cent re gro up s interested in AWW acti vities in Qld. and Northern NSW who may be interested in sta rtin g an A WW A regional bra nch co mmit tee and a rra ngin g a progra mme of 3-4 technical meet ings each yea r in which t he Qld. Bra nch could be of assista nce. Membership is still increasin g with over 20 new applicat ion s in the past two month s. " LIF E IS GREAT IN THE SUNSHIN E STATE !"

SOUTH AUSTRALIA Th e third Bra nch meeting for the year was held o n Friday th e 30th May at th e Institution of Engineers, and the intere t in the topic was shown by the number of memb ers attendin g despite the incle ment weather. Dr. A. J . McMichael of the C.S. l.R.O . Di vision of Hum an Nutrition presented th e address on " Heavy Metals & Health". Dr. McMichael introduced th e topic by il lustrating the best known rece nt ex amples o f waterborne cadmium and mercury poisoning . The ita i-it ai and min emata di seases occurred in Japan in the ear ly 40 's and 50's and invol ved substantial ex posures. However it was em ph a sised th a t other fac tor s includin g socio eco nomic stat us, sex and deca lcification were co ntributor y to the diseases. Dr. McMiachael proceeded to discuss th e effect of lead ex posure and elabora ted on the possibl e effect lea d may have on foetal growth a nd on po st-natal development. H e then described his current wo rk , the effect of lea d on foetu ses in the industri a l town of Port Piri e. Th e project is long-term and will in volve monitoring of pregna nt women and their children's development up to 7 years of age. , Th e address was well received as was the elabor ate supper served. At th e Jul y meeting, Profess or John Burton from the Uni ve rsit y of New England in Arm id ale, N.S . W. , ~resented a nd address entitled 'Recreation on Water S upply Rese rvoirs '. By way of introd uction, Professo r Burton gave examples of such use of reservoirs in Engla nd, U.S .A. a nd Australia . He then proceeded to di scuss in detail an experiment which has been conducted on Malpas Reservo ir in Armid ale over four summ er season s. Sailing is now permitted eve ry weeke nd and no ad verse e ffects on water qu alit y have been detected. However it was pointed out th a t th e water prior to recreationa l use had high nutrient· leve ls and significant a lgal blooms. Professor Burton stressed the importa nce of goo d management planning with restri cted access a nd acti vities where necessary, for ex ample, away from th e outl et. The success with Malpas Rese rvoir is s·uch that an agreement is being sou ght with th e City Cou ncil to establi sh permanent usage.' . Professor Burton empha$ised that the suc cessful use of one reservoir need not necessa rily mean that he a dvocated such usage for all reservoirs. Every reservoir shou ld be treated as a separate issue with th e approach dictated by rationality and respon sibility and the importance of comprom ise. 9

NEW SOUTH WALES Branch Activities Th e June meeting, on the 20th, was one of the most popular social function s in th e Branch's calendar, the Dinner-Wine Tasting at Len Evan's Restaurant. Fifty members and their wives thi s year quaffed and a te their wa y throu gh Len' s offerings with grea t gusto. In July , activity was truly technical with a meeting o n the 16th at the Sydn ey Chamb er of C ommerce Board Room. This was well attend ed by fort y members to hear Ralph Wooll ey's paper on Alum Recovery at the Brisbane City Council's Mt. Crosby Water Treatment Works. Ralph described th e pioneering work don e by th e Council ov er the last eight years in in ves ti ga ting th e environmental problem s created by di scharge of alum wastes and th e mea ns and details of plant des ign adopted to overcom e th em for the 700 ML/ day throu ghput. In a well received departure from previous practice, this yea r 's N.S . W . Bra nch Annu a l General Meeting on August 13th , was held at the Royal Automobile Club after, rather th a n befor e dinner. In spite of (or perh aps becau se of? ) the pleasant table wines provided by R.A .C., the A .G .M. was a ha ppy occasion with votes o f th a nk s from th e 55 members present to Presid ent, Mike Dureau who ensured a n interes ting and vari ed technical and socia l calendar through the year, Rod Le hm a nn fo r hi s hi g hl y e ffi c ient Secretaryship, Dave Stevens, Hans Bandier and Peter Mitchell for their past and continuing man agement of the Regional Conferences and oth er Committee members whose acti ve and generous contributions contributed to the finanical and professional success of th e year . Office holders for the comin g year are: Pres id ent (and Federal Councillor), M. B. Dureau ; Vice Pres id ent, T. M. Smyth (who will continue as C orrespond ent for 'Water ' ); Sec retary, R. Lehman; Treasurer , J . Brown; Co mmittee is R. R. Ash, H . Bandier, G. B. Douglass , J. Es la ke, R. Edwa rd s, N. Fleming (Newcastle Sub-bran ch) , P . W . Hughes, Dr. T . Jud ell, T. Lawson, P . J. Mitchell, G. W. Montgomerie, D . Stevens, M . P. Tseng, T . J. Turyman, K. A. Waterhouse (Councillor) . Th e Branch has prepared and distributed an Annual Report of professionally hi gh stand ard which has received favourable com ment. Copies are avail able for an y Branches wishing to emula te . Following completion of hierarchical Bra nch business , J. G . Atherton (Reader in Virology at the University , of Queensland), presented his paper "Use of Magnetite for Removal of Virsuses from Water and Wastewater" . Atherton fir st introduced th e varieties of viru ses , their characteristics and behaviour in wa ter, and problems relating to their detection and enum eration. For example , virus counts in raw sewage range fr om 200-500,000 infectious viru s particles per litre of raw sewage, while infection of man can result, for example , from only one pa rticle of poliovirus per litre. The speaker then developed and described his studies relating to the use of magnetite a s a viru s remover. Basically enteric virsues

beha ve as charged collidal particles and fine particles of magnetite behave similarly. If the isoelectric points of the two differ , pH can be chosen where viru ses will be electrostatically bound to the magnetite. Âˇ Using an easily manipulated bacteriophage MS2 and poliovirus, tests showed they retained their full infectivit y from pH3-l l, but exposed to magnetite were largely adsorbed . Tests also indicated that suspended materials such as clay interfered with viru s adsorption but the effect could be largel y ov e rcome by addition of s uit a bl e polyelectrolyte. On September 19th the Annual Dinner Dance will be held at the Silver Room , Grace Bros. , Chatswood (as this issue goes to Press), a good response is aniticipated. For October a joint meeting is planned with the Institution of Engin eers at the Institutions Auditorium on the 28th. Papers will be presented by Mr. M . Wh yte of th e M.W .S. & D. Boa rd and Mr. J . Child of Electrolux on "Vacuum Sewerage Systems ". Preparation for th e Symposium "Water Supply Demands in Towns and Cities, Its Estimation and Management " being organi zed jointly with the Wat er Resea rch Found ation of Australia, is proceeding smoothl y. Th e Symposium will be held in the Fl ying Ange l House on November 5th. Furth er details are given on page 30 o f this issue . State News

Peter Mitchell of Alfa Laval departed earl y September for a tour of Denmark and Sweden to stud y sludge processing and oil/w ater polluti on controls in those countries. H e will return through th e near- Pacific regions on a six wee ks visit aim ed primaril y a t the palm oil process ing and wastewater fi eld s . Th e Branch Committee welcom es the suggestion th at Bra nch News should be augmented by an account of Sta te activities .

VICTORIA Branch Activities

In th e 'Garden State' winter is drawing to a close (hopefully) and with it , th e end of a busy Branch year approaches, a year in whi ch meeting coverage has ranged from ultra high purity water to the salinity of th e River Murray - quite a spectrum. In June , John Alexander o f Kent Instrum e nts des cribed th e sophi sti ca ted automatic analyti ca l systems used for th e control of wat er circuits in high-press ure boilers . Complete with air-conditioned instrum ent cubicle th ese sys tem s can form a tid y package at a mere $250,000 or so, im pressive but not a la rge item in comparison with th e $200 million or more of the plant prot ected. The July meeting provided a most rewardin g di scussion of water in th e context of public health , both as a positi ve agent for th e safeguarding of such and , in contrast, as a poss ible carrier of pathogenic agents. Dr . Barr y Fish of th e Health C ommission in "Health Aspects of Water" discusse d hi stor y, epidemiology and toxicology. H e pointed out tha t while con ventional treat-

ment a nd chlorin a ti on practi ca ll y elimina ted bacterial waterborn e diseases, emphasis has now shifted to virus transnfiss io n and th e poss ible chronic effects of chemi ca ls from in dustr y and agriculture. Ano th er in creas in g dange r is from pa rasiti c diseases, promoted by the speed o f international travel. In Au gust, the Bra nch was give n an ove rview by Keith C oll et of th e pr esent state of salini sa ti on in North ern Victori a and th e Ri ver Murray . H e described the vario us strategies now employed or prop osed for co ntrol a nd comment ed upon cost/ benefit ratios of different schemes. C omin g event s incl ude a paper o n Mag neti c Ion Exc ha nge in Se pte mber and the Spring Con Ference to be held at Sovereign Hill , Ba llarat, Octob er 24-26 - a most approp riate venue as th e timi ng marks th e Centena ry of the Ball arat W ater Commission ers. Closu re of the yea r will be mar ked by the usua l ladies night bu t in an unu sual fas hi on by spit -roasting an ox a t Fergusons Win ery, complete with local win es . For the comin g yea r, A la n Longs taff assum es th e Presidential offi ce. Robin Tovey a nd Ken W ood (th e willing horses) continu e as Secreta ry and Trea surer res pecti vely a nd the Co mmittee will be: R. B. Turn er , W. J . Delfer, W. M. Drew, J. S. Rogers on , A. Stromm , M. A . Co rnell , J. E. North , R. W. Vickery, F. R . Bishop , I. M. Low th er, R. F. Pay ne, J. W. P ar ker, Dr . P . R. Naidebaum, Pro f. F. La wson. John Bayles will continu e as Bra nch Correspon dent and R. McMillan as Minute Secretary . Frank Bishop a nd Allan Stro mm will continu e to serve as Federal Councillors and Bo b Sw inton will continu e to lend hi s uniq ue combina tion of charm and capacit y, now as Past Pres id ent. State News A m ost interes ting pilot pla nt study will comm ence in Nov emb~- to investigate mean s of upd a tin g th e Lil yd a le Sewe r age Authorit y's main plant consistin g of tricklin g filters a nd lagoons. Th e stud y will assess nitrogen and phosphorous rem ova l treatment options and will be carried out in Envirot ec h pilot plant using th e Bardenpho process . Phosphorous removal is no w considered necessary by the Victorian EP A to protect th e down stream Sugarloa f Rese rvoir o f th e M.M . B.W. from nui sance algae in the Sum mer months. Consultants to the Lilyda le Authori ty, Camp Scott and Phurphy P / L will ma nage the stud y in conjuncti on with th e Authori ty and th e Ministr y of Water Resources .

OUR NEXT CONVENTION PERTH IN APRIL!

BE THERE! See page 29

WAT E R

NEWS

10th Bienniel Conference Th e 1980 Co n fe rence of th e Internation a l Associa tion for Wa ter Polluti o n Resea rch was held at Sherato n Centre H o tel Toronto Jun e 23-27th . C . D. (Gu y) P arker, a n Au stralian Represe nta ti ve on th e Governing Boa rd provides th e followin g report . Reg istration was disa ppo intin gly low with 548 registra nts a nd some 150 wives a nd accompa n ying perso ns. Australi a as usual was well represent ed with 2 1 regist ra nt s a nd so me 10 acc ompanying persons. On e hundred a nd sevent y three papers had been subm itted , of whi ch 68 we re selected for prese nt a tion a t th e Confe rence. Th ese cove red a wid e fi eld and we re of hi g h technical competence. Of th e pa pers no t prese nted some 26 will proba bly be acce pted for publicatio n in Wa ter Resea rch. T ec hni cal tours during th e Conference were to local sewage and water treatm ent pla nts a nd the Resea rch Laboratori es of th e Ca nad a Centre fo r Inl and Wa ters, at Burlington , where int eres ting pilo t plant fac iliti es were o n display . During the mee ting a film was shown by Wes t German d elegates from Hamburg sho win g tec hno log ica l de ve lopm e nt s in plasti c lining of la rge sewer pip es to protect aga in st H 2S cor ros ion. The prese nta tion wa s di sappointing in its lack of reference to or recognition of th e ex tensive Au stralian achi evements in thi s area. Th e Social prog ramme was e njoya ble a nd includ ed th e tradition al Con fe rence Banquet held a t the Confere nce Hotel whe n the Gues t Spea ker, the Ca nad ia n Federal Minister fo r the Environmem , gave an int e res ting assessment o f the infl uence of acid ra in fro m th e combin at ion o f sulphur bearin g fuels, on th e so ft inland wa ters o f Eas tern Ca nad a . Anoth er hi ghli ght was the Reception o f Delega tes a t th e C ity Rotund a in the C it y Hall Building, jointly by th e M ayor o f th e City of Toronto a nd the Mayor of Metropo li ta n Toronto. Th e ladies had enjo yable trip s a ro und th e Cit y to a n int eres tin g ha ndi craft centre o utside th e C it y and to Niaga ra Falls a nd Niagara on th e La ke. An informal m eeting on virologica l ac tivi ties led to th e fo rmati o n of a n Int ern atio na l Study Gro up on Wat er Vi rology. Australia was re presented at th e meeting by Mr. Ia n Smalls a nd C. D. Parker. Dr. W. 0 . K. Grabon of South Africa C.S . l. R. Na tiona l Institute of Water Research was elected Con vene r of the Group . Furth er inform ati on will be av ail a ble fr o m Dr. Grabon or C. D . Park er. Th e Presid ent of th e Assoc ia ti o n fo r th e nex t two years is Pro f. R. S . E ngelbrecht of Uni ve rsit y of Illin o is and Vi ce Pres id ents, D . E. Kunt ze o f Wes t Germany a nd Prof. Pa ul

WAT E R

Ha rre moes of De nma rk . Mr . E. Walde r (A ust ra li a) was re-elected C ha irma n of th e Fina nce Commi ttee . A spec ially con vened meeting o f the Governing Board gave consideration to the future developm ent of Association acti vities. From thi s and in for ma l group discuss io ns a picture emerged of alread y determ ined a nd prospecti ve activ ities prov id ing a va lu a ble approac h to the futu re. At t he Board meeting the te rm o f a ppoi nt ment of Mr. Ro n Fairhall as Secreta ryTreasurer terminated and Mr. F ai r hall unfor t una te ly was un a ble to con sid er a furth er term o f a ppointm ent. The positi o n is curre ntly be ing advertised in Euro pe and U .S. A. New Associa tion premi ses are bein g so ught. Corres po ndence for the present should be direc ted to th e Secre tar yTreas uru er at th e present address. Communi ca ti o n to th e Executive Editor should be directed to Dr. J enkins, Birmingha m address .

sitin g and la nd scapin g, a rchitec tur e, po lluti on fro m vessels. • P o lluti on Prevention - C oastal Wa ters - t rea tment versus sea o utfa ll s, transient popul a tions, nutri ent problems, siting la nd sca p i n g , a rchit ec tur e, slud ge di sposa l. • P o lluti on Preve ntion - Indu strial Was te Problems - trea tm ent versus di scha rge to sewer, toxicants, futu re p roblems. • Legisla tion a nd Admini stra tion Aspects - mon itoring and surveillan ce. A second lea fl e t containing th e advan ce progra mme is no w ava il a ble from th e Sec reta ry. International Workshop on Requirements Application and Practical Experience of Control and Automation.in Water Quality Monitoring

The third work shop will be held in Munich

Left to right at Toronto: Leon Henry (Aust.), Prof. P. Harremoes (V. Pres.), Prof. R. Engelbrecht (Pres.), Guy Parker (Aust.), Dr. E . Kuntze (JI. Pres.), Ted Walder

(Aust.). 11th Biennial Conference -

Capetown, 1982

The Conference dates will be March 29 to April 2 and Past President Dr . G. Sta nder will be Con ference Pres ident. The call for papers has alread y been iss ued , closing on Ju ne 1st , 1981. P ossible contributors should cont ac t o ne of th e Australia n members o f th e Gove rning Board. The Environmental Impact of Man's Use of Water

Thi s specialised con fere nce will be held a t Bright o n, U. K. o n November 3rd to 7th , 1980 . Th e progra mme is di vid ed into th e follo wing themes : • Co nserving th e Environm ent - conse rva ti o n , pl annin g a nd econo mi c aspects. Problems in Wa ter Reso urces Develop ment - con stru cti o n, o perati o n, distribution , recrea tion ve rsus publi c health. • P o lluti on Pre ve ntion - In land Wa ters sewerage trea tm ent, stormwat er, slud ge disposal, odour control , noi se contr o l,

a nd Rom e on 20th to 26th Jun e 1981 and will begin immedia tely before th e Europea n Sewage a nd Re fu se Symposium (EAS) and th e Intern ational Sewage and Refu se and City Cleaning Ex hibition (!FAT) . P a rticula r emph as is will be given to practica l ex perience in control and a utoma ti o n leadin g to impro ve ments in pla nt efficiency that del&y th e need for ca pital expenditure , produce better qualit y efflu ent s a nd conserve energy. Micro-pollutants in the Environment A specialised conference will ta ke place in Brussels on November 22 to 25 , 1981 . Pa pers and di scuss ion will be directed to the fo ll o wing specific aspects o f micropollut ant s : na ture a nd origin , influence on surfa ce waters, effect on groundwa ter re-chargin g, result a nt effect on disin fect ion of trea ted waste wa ter, reuse o f sludge and treat ed wastewa ters, elimination , methodology of resea rch , conclusion s a nd proposa ls for control a nd furth er resea rch.

MERCURY IN AQUATIC ENVIRONMENTS A GENERAL REVIEW L.A. Nagy and B. H. Olson INTRODUCTION The ut il ization of mercury related tec hnology after the 1940's resu lted in the direct or indirect release of many forms of mercury into the aq uatic environment. Direct sources of mercury contamination includ ed m ost industrial users , whereas indirect sources were inadvertent releases of mercury. T he use of mercury containing fungicides in agr iculture lead to wide spread indirect a qu atic conta mination through runoff. From the environm ental point of view , direct sources had more intensive ecological effects than ind irect so urces of mercury pollu tion (Hartung a nd Dinm a n , 1972). The main sources of mercury enterin g a quatic env ironments were from t he chl or-alkali , paint, pulp and paper, and catalyst industries (Katz , 1972). It was esti mated that t he environmental release of mercury just from the chlor-a lkali indu stry in the United States an d Canad a by 1968 was approximately 600,000 kilogram s per year (D'ltri, Âˇ 1972b) . Beca use recycling of mercury was more expe nsive than its market pr ice, few industries attempted to recover the mercury lost during production processes . Contamination of t he environment most frequently occ urred when trace amounts of mercury were released fro m the above -ment ioned indu stries over extended periods of t ime (NASNRC Pane l on Mercury, 1978). T he conseq uences of mercury pollution from ind ustrial sources were recognized in the late 1960's a nd early 1970's. Steps were taken in most ind ustri al ized countries to red uce direct releases of mercury or mercu ry con ta inin g compound s into the environment . In the U.S., for example, companies were required to limit their mercury discharges to approxim ately 0.2 kg/ d ay (K atz, 1972). As a result of relatively effective reg ul ations a nd controls, the importance of mercu ry as an environmenta l poll utant has decreased considerab ly, but not disappeared completely. A number of environments have been so polluted that hundreds of years m ay be required for their natural decontamination (Ka tz, 1972). Although indu strial discharge of mercury into aquatic environments has virtually stop ped , other , potentially harmfu l sources such as sewage efflu ent disposal (D'ltri, 1972b ; Eganhouse, Young a nd Johnson, 1978; Kl ein a nd Goldb erg, 1970) have emerged. A number of books (D ' Itri , 1972a; Hartung and Dinman, 1972; Jones, 1971; NAS-NRC Panel on Mercury, 1978; UK-DOE Poll ution Paper No. 10 , 1979) and review articles (K atz , 1972; Krenke!, 1974) have been written on the extent a nd consequences of mercu ry con tam in ation . The most recent bibliography containing some 4 ,000 references on the subject of environmental mercury pollution has been compiled by Taylor (1977) .

1977). Initi all y the probl em was not id entified as mercury poisoning and so was given the name of Min am ata disease. Since then, th e latter na me, techni ca ll y incorrect, has been often used to refer to other cases of environ menta l organo -merc ury poisoning. The Minamata outb reak was followed by other , fortunately small er outbreaks , a ll resu lting from the consumption of seafood from mercury contaminated env ironm ents. Between 1965-1974, 520 cases of methylmercury poisoning were identified in Niigata , Japan (Tsubaki and Iruk ayam a , 1977), res ulting in at least six . ffici ally recognized deaths (Leong , Olson, Cooper, 1973). Nearly 200 cases of elevated blood methylme rcury levels were reported in Sweden (Birke, et al. 1972; Skerfving, 1974). Approx im ate ly 40 cases of mild methylmercury poisoning were reported from the Lake St. Clair region of Canada in I 975 (NAS-NRC Panel on Mercury , 1978). Apart from outbreaks caused by t he consumption of food from mercury polluted aqu atic environm ents, there have been a number of outbreaks ca used by th e consumption of bread prepared from seed treated with methylmercury fungicides. Although these outbreaks were not the res ul t of aquatic mercury pollution, they were nevertheless the result of mercury mismanagement and will be mentioned briefly. The largest of these outbreaks, between 1971-1972, in Iraq, resulted in over 6,000 reported cases and nearly 500 reported deaths (Bakir et al., 1973). Two years prior to th is incident , several members of a fa mily in Alamogordo, New Mexico, U .S., suffered serious methylmercury poisoning when they consum ed their home raised hog which had been fed on methylmercury treated grain (Hinman, 1972). This incident prompted the U.S. Department of Agriculture to deregister the use of alkylmercuri a ls for seed treatment on 9 March , 1970 (Lofroth , 1970). As a res u lt of the Minamata a nd Niigata (Japa n) outbreaks, indu strialized countr ies beca me aware of the consequences of environmenta l mercury pollut ion and thus fa r, in these countries, other large scale outbreaks have been averted due partly to environmental legislative constrai nts a nd partly to the ability of il)du stries to a llocate revenu e for pollution control (Katz, 1972). It is doubtful however that less indu stria lized cou ntries, or ones currently und ergoing a period of rapid indu strialization will be that fortunate . A number of third-world coun tries currently experiencin g a per iod of indu stria lization sim il ar to that of Japan in the 1950's are becominl potential victims of futu re env ironmental mercury poisoni ng o utbreaks (Komerwar et al., 1978; Menasveta a nd Sawangwong, 1978; Suckcharoen, Nuorteva and Haesaenen , 1978).

TOXICOLOGY OF MERCURY COMPOUNDS HISTORY OF ENVIRONMENTAL MERCURY OUTBREAKS Mercury poisonin gs can be divid ed into two main types ; occupational and environ menta l. Although cases of occupation al mercury poisonings , especia lly in mine workers have been recorded since ancient times , the first large scale environm ental mercury outbreak occurred in the town of Minamata , southern Japan , between 1951-1972 (Tsubaki and l ruk ayam a, 1977). For several years prior to the outbreak, a cata lyst facto ry was releasing efflu ent containing methylmercu ry into Minamata Bay . High levels of methyl-m ercury were bioacc umulated by fish. The consumption of such contaminated fish produced elevated levels of methylm erc ury in th e human population. Over seven hundred officially recognized cases of organo-mercury poisoning occurred, resu ltin g in 82 officially recognized d eaths (Tsubaki and Irukayama ,

Loslo A. Nagy is an Honours Graduate of A.N. U. and Graduate Student and Teaching Assistant in Social Ecology at th e University of California, Irvin e, USA. Dr. Betry Haak Olson is Assistant Professor, Program in Social Ecology, University of California. It is hoped to follow this paper with a review of decontamination methods of mercury polluted wastewaters by the Co-authors in a f uture issue of 'Water'. 12

The toxicology of elementa l, inorganic and orga nic forms of mercu ry are sign ifi cantly different, not only in the extent they are a bsorbed by the hum an body. but a lso in the degree of injury they inflict on the biochemistry of the body (Goldwater, 1974a). Elemental and inorganic form s of mercury are a ll poisonous to som e extent , but are not absorbed very quickly a nd once absorbed , approximately 50% is soon excreted. Orga nic forms of merc ury ca n differ considerably in their toxicology, ranging from med ica lly beneficial to high ly poisonous (Goldwater, 1974a). Of the three ma in classes of organomercurials, aryl, alkoxy and a lkyl, the a lkyls are the most poisonous and unfortunate ly, environmentally the most predominant (B ache, Gutenmann a nd Lisk, 1971; Westoo, 1973). Alkylmercurials such as methyl and ethylmercury are absorbed fas ter and excreted slower tha n inorganic forms. They can also accumul ate in various tissues of the body such as kidney, liver a nd the b rain , but the critical organ in hum ans is the central nervous system (Ts ubak i and Irukayama , 1977). Methyl-mercury can pass the bloodbrain barrier a nd accum ulate in the brain, where subsequent cell destruction can produce the characteristic symptom s associated with envi ron menta l mercury poison ing. These sym ptoms in increasing severity are excess ive fatigue, headaches, amnesia Ooss of memory), blurred vision , paraesthes ia (numbness of the extremities), involunta ry mobilization , blindness, deafness, loss of consciousness and finally WATER

death (Dinm an and Hecker, 1972). The disease is considered usually reversib le up to the symptoms of paraesthesia. However, in most cases, early symptoms of alkyl mercury poisoning are difficult to diagnose due to their nonspecific nature (NAS-NRC Panel on Mercury , 1978). Alkylm ercurials in genera l and methylmercury in particular can also cross the placental barrier, making the fetal brain the criti cal organ in pregnant fema les sufferin g from environmental mercury poisoning. It appears that the growing fetal brain is particularly sensitive to methylmercury (Snyder. 1971), such that levels of methylmercury too low to produce severe symptoms in the mother , can still ca use severe congen ital brain damage in the developing fetus. (D' Itri, 1972a; NASNRC Panel on Mercury , 1978) .

INTERNATIONAL REGULATIONS AND GUIDELINES Because methylmercury compou nds have no known useful metabolic function in the human body, their intake, by the consumption of food, represent unnecessary contamin ation. Ideally food shou ld contain no measurab le levels of mercury, however, certa in social and economic factors have necess itated that some levels of contam ination be accepted. Fish and shellfish are the sin gle most important source of mercury (and thus methylmercury) in the hu man diet and for this reason a number of cou ntr ies have established limits for mercury concentrations in fis h . These limits are variab le from country to country, as a number of factors such as average daily seafood cons umption and average body weight of citizens contribute to the de termination of each nation's regulations and / or guidelin es. T he limits for total mercury conce ntration in seafood for various countries is li sted in Table 1 (modified from NAS-NRC Panel on Mercury , 1978). The scientific legitimacy and va lid ity of the Canadian and U.S. limit of 0.5 µg / g has been strongly questioned (Goldwater, 1974b) and although the sta ndard has remained unchanged since 1970, it may be mod ified as further data become avail abl e.

TABLE I: TOTAL MERCURY LIMIT FOR FISH SOLD IN VARIOUS COUNTRIES

COUNTRY Austra lia - New South Wales - South Australia, Victoria Canada West Germany Japan Sweden United Kingdom United States

TOTAL MERCURY LIMIT WET-WEIGHT BASIS (ug/ g or ppm)

0.5· 0. 1 0.5 0.5 0.4 1.0

none•• 0.5

WHO / FAO Provisio nal tolerance intake (0.3 mg/ person/ week) • under review (Bebbington, et al., 1977) •• enforcement officers are asked to exercise vigilance and prevent dumping of co ntaminated fish from other countries .

ACCUMULATION BY FISH In aquatic env ironments polluted by mercury, fish rapidly concentrate the poll utant (usually in the form of methylmercury) in their body tissue. Fish from both freshwater and marine environments have been reported with mercury concentrations above the generally accepted limit of 0.5 µgi g (ppm). Levels above th is va lue have been reported in a number of countries including Australia (Bebb ington et al., 1977), Austria (Tehereni, Steh lik and Hinteregger, 1979), Canada (Annett et al., 1975; Greig a nd Seagram, 1972), Finland (Hattulla et al., I 978) Israel (Y annai and Sachs, 1978), Japan (Kitamura, 1968), United Kingdom (Ga rdner, 1978) and the United States (Bails , 1972; Ko li et al., 1976; Sheffy, 1978). It was initi ally thought that this bioaccumul ation was the result of concentration alon g the food-chain (D'Itri. 1972a) however, recent evidence suggests that diffusion may be the single most important factor (NAS-NRC Pa nel on Merc ury, 1978; Ottawa River Project Group, 1979). It is thought that methylmercury from the surrounding water diffuses across the cell membrane of fish in order to attain eq ual concentrations inside and outside the orga nism. However , once inside the cell the methylmercury becomes bound to the sulfhydryl groups of proteins. This bindin g maintains th e unb ound methylmercury concentrat ion grad ient across the cell membrane and allows further WATER

diffusion of methylmercury into the organism . Thus, even in environments with relatively low levels of methylmercury pollution , fish can bioaccumu late large quantities of su lfhydryl-boltn d mercury.

BIOLOGICAL CONVERSIONS OF MERCURY It was initially thought that inorgan ic mercury compounds were relat ively inert and consequently could be discharged into the environment. This ass umption proved to be incorrect when it was es tablished that inorganic forms of merc ury can be biologically converted to more toxic forms by aquatic micro-organisms. (Although mercury ca n be transformed by physical and chemical agents , the most importa nt transformations are biologically induced .) The two main types of reactions mediated by micro-organisms are methylation and demethylation of mercury (Fig. 1). Both these reactions have important ecological and public health conseq uences.

Air

Hgo _,.,-.....;;;. d_e_m_e_t_h.._v_la_t_i_o_n__ C H Ht-- Fish 3

12+

methylatlon

Figure 1. Main biological conversions of mercury. Methylation reactions are important because inorganic merc ury is transformed into the more toxic organic, namely alkyl form. The resu ltant methylmercury is rapidly accumul ated by fish. The regular consum ption of fish contain ing high levels of methylmercury ( :'.'. 4 µgi g) produces progressively more severe symptoms of methylmercury poison ing. A number of micro-organisms present in aqu atic sediments have the ab ility to methylate inorganic mercury under either aerobic or anaerob ic conditions (Hamdy and Noyes, 1975; Olson and Cooper, 1974 and 1976 ; Wood, 1974i. T he most important coenzyme for methylation appears to be vitam in B 12• Bacteria are the main microbial group responsible for methylation , althou gh somer fun gi can also perform the transformation (Landner, 1971 ; Vonk and Kaars Sijpesteijn, 1973). About 10 % of the inorganic merc ury present in aqu atic sediments is converted into methylmercury each year (Stopford and Goldwater, 1975) and although this apIJl:ars relatively minor, it is important to remember that the latter compound is 50-100 times more toxic than the former (S umm ers and Silver, 1978). Demethylation of methylmercury by sed iments or by micro-organisms present in sed iments, results in the release of elemental mercury whi ch could vaporize to the at mosphere. T he process essentially detoxifies the mercury compound and releases the metal to the atmosphere, where, in small concentrations, its presence is relatively harmless. About 15% of the bacteria isolated from mercury polluted sed iments have the abi lity to detoxify the compound . The demethyl ating ability is genetica lly controlled, however the genes are not part of the bacterial chromosomal material. Instead, the demethylating genes are carried on extrachrom osomal factors called plasmids. (Plasmids are circular segments of DNA , usually 20-200 genes long, with the ability to reproduce and be passed from cell to cell as well as between cells .) A number of demethylatin g plasmids, with different res istance patterns have been investigated (Summers and Si lver , 1978). It appears that the genus Pseudomonas is particularly adapted to demethylation reactions (Spangler et al., 1973; Stopford and Goldwater, 1975). Both methylation and dem ethylation processes exhibit seasonal fluctuations. A recent investigation of methylmercury production in mercury-enriched sed iments (Olson , 1978) has indicated that these seasona l fluctuations are ind ependent of a number of physical and chem ical parameters. Seasonal fluctuations in mercury res istant bacteria isolated fro m sediments containin g high , medi um and low levels of mercury, have been shown by Nelson and Colwell (I 975). These mercury resistant bacteria are the ones primarily responsible for demethylation processes. 13

TABLE 11: MAIN USES OF MERCURY IN THE UNITED KINGDOM IN 1975 ACTIVITY chlorin e production primary batteries paints dentistry agriculture and related uses electrical/control in struments catalysis laboratory chemicals pharmaceuticals adhesives miscell aneous (munit ions, pumps, photography, fire works, textiles)

1000 kg USED 283

80 34 30 28 14 11 10 2 l

sewage slud ges in the U.S. for 1973 was 46,000 kg (NAS-NRC Panel on Mercury, 1978). Of th is amoun t about 8 % was lost to the atmosphere, 43% to water a nd 49 % to soil. There appears ttJ be a background concentration of 0.1- 7.9 ppb mercury in public sewer systems even in the a bsence of any indu strial discharge (Evans, Sullivan a nd Lin, 1973) . The mercury in the sewage becomes concentrated in the sewage sludge, such that dried slud ge from rural as well as urban sewage plants can conta in 1-26 ppm mercury (Va n Loon , 1974). The disposal of sludge effluents into aquatic environments has resulied in localized elevated mercury levels (Eganhouse, Yo un g and Johnson, 1978; Oliver, 1973; Smi th. Nicholson and Moore, 1971). The land disposal of such sludges also produces environmental problems (Jorgensen , 1975; Oliver a nd Cosgrove, 1975; Van Loon , 1973).

DECONTAMINATION AND POLLUTION CONTROL PRESENT SOURCES OF MERCURY POLLUTION Mercury is a widely used compound in industri al societies, resulting in a multitude of possible pollu tion sou rces. Prior to 1970 the most important sources of mercury p ollution were localized industrial d isc harges, usually from chlor-alkali pla nts . This situation was exemplified by a Sarn ia, Ontario chlor-alkali plant that discharged about 100 kg of mercury per day (Katz , 1972). As a resu lt of increased awa reness in 1971-1972 a nd subsequent strict administrative action, localized discharges have been co nsiderab ly red uced. Thus, present sources of mercury pollution are gen era lly of the low level but wide distribution type. Present sources of mercury emi ss ion into the environment can be divided in to three main categories: i) releases resulting from direct industrial use of mercury or merc ury based compo und s, ii) releases resulting from the combustion of foss il fuels such as coal and oi l, all of wh ich conta in trace quantities of mercury , iii ) releases resul ting from the disposal or burning of urb an garbage sewage sludge which contai n quantities of mercury du e to the near ubiqui tous presence of the metal in manufactured products. T he globa l annu al release of mercury, resulting from hum an activity has been calc ul ated at 5 million kg (UK- DOE Pollution Paper No. 10, 1976). T he principal uses of mercury in the United Kingdom in 1975 are indicated in Table II (UK -DOE Pollution Paper No. 10, 1976). Each of

Mercury pollu tion control is composed of two main, interrelated aspects:i) control of future release of mercury by application of recovery and recycling techni ques and, ii) decontamination of presently polluted areas. A variety of recovery and recycling techniques, being developed or already in operation, h ave been reviewed by; nes (1971) and Krenke! (1974). A s umm ary of procedures avai la ble for tht: treatment of liquids contain in g mercury compounds is presented in Table III. The decontamination of presently polluted aq uatic environments in most cases involves t he remova l of mercury from the contaminated sediments. A number of procedures have been suggested, including dredging or buria l of sed iments, ama lgamation with alumi nium and pH modification, but unfortunately none of the currently available procedures a re practical or cost effect ive (Krenke!, 1974). In most situations the decontamination proced ure wou ld be ecologica lly more harmfu l than the pollutant und er consideration. At the present tim e the most effective decontamination option of curren tly polluted areas appea rs to be natural cleansing, which , d epending upon the level of pollution , could require 100-1000 years (Katz, 1972). As present physica l and chemical decon tam in ation options appear relatively ineffective, a better understanding of microb ial demethylat ion processes should be encouraged . The formu lation of future microbiological decontam ination options seems extreme ly feas ible in light of microbia l d emethylation processes in sediments which volatilize mercury. Thus the removal of mercury from the aq uatic sediment environment could be possible by t he utilization of micro-orga nisms.

TABLE 111: SUMMARY OF PROCEDURES AVAILABLE FOR THE TREATMENT OF LIQUIDS CONTAINil'1G MERCURY COMPOUNDS PROCEDURE activated carbon activated carbon activated carbon amines

cellulose cellulose cellulose/cotton coagulation (alum) cotton ion exchange resins peanut hulls/bark rubber silico n alloys sodium borohydribe starch xanthate . sulfide ultrafiltration wool (modified)

LIQUID raw and treated drink ing water distilled water and mercury trickling filter effluent chlor-alka li plant wastewater distilled water and mercury distilled water and mercury distilled wa ter and mercury raw and treated drinking water disti lled wa ter and mercury chlor-a lkali plant wastewater distilled water and mercury distilled water and mercury chlor-alkali plant wastewater chlor-alkali plant wastewater distilled water and mercury chlor-alkali plant wastewater copper indu stry, scrubber blowdown wastewater distilled water and mercury

these uses can res ult in a potential release of mercury into the env ironment und er category i) a nd iii) above. Alth ough category ii) results in the release of mercury into the atmosp here, it is still an importa nt source of aquatic pollution , as most atmosp heric mercury is eventua lly d eposited on soil or in water. It h as been estim ated that the worldwide combustion of coal alone releases 500,000 kg of mercu ry each year (Katz, 1972). Category iii) is becomin g a n increasingly importa nt source of mercury contamin ation . Total mercury losses to the environment from

REFERENCES Logsdon & Symons, 1973 Thiem, Badorek & O'Connor, 1976 Argo & Culp, 1972 Moore, 1972 Marchant, I 974 Gasparri, et al., 1976 Snyder & Vigo , 1974 Logsdon & Symons, 1973 Roberts & Row land , 1973 Rosenzweig, 1971 Henderson, et al., l 977 Wheeler & Hamdy, 1977 McKaveney, Fassinger & Sti vers, 1972 Rosenzweig, 1971 Swanson, et al., I 973 Bouveng, I 972 Bhattacharyya, Jumawan & Grieves, 1979 Freeland, Hoskinson & Mayfield, 1974

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BAILS J. D. (1972) . Mercury of fish in the great Lakes. pp . 31-37 in Environmental mercury contamination, Hartung R. and Dinman B. D . (Eds.) Ann Arbor Publishers , Ann Arbor, Michigan. BAKIR F. , DAMLUJ I S. F., AMIN-ZAKI L. , MURTADHA M., KHALID ! A., AL-RAW I N. Y., KR IT I S. T. , DHA HI R H. I. , CLARKSONT. W. , SM ITH J. C. AND DOHERTY R. A. (1973). Me1 hylmercu ry poisoning in Iraq. Science 18 1:230-24 1. BEBB INGTON, G. N ., MACKAY N. J., CHOY JKA R., W ILLIAMS R. J. , DUNN A. AND AUTY E. H. (1977) . Heavy meta ls, selenium and arsenic in nine species of Au stralian commercial fi sh. Aust. J. Marine Freshwater Res. 28(3):277-286. BHATTACHARYYA D., JUMAWAN A. B. JNR . AND GRIEVES R. B. (I 979). Charged membrane uhrafi l1ra1ion of heavy meta ls from nonferrous metal W.P.C.F. Journal 5 1: 176- 186. BIRKE, G., JO H NELS A. G., PLANT IN L . 0., SJORSTRANTD B., SKERFVING S. AND WESTERMARK T. (1972). Humans exposed to methylmercury through fi sh consumption. Archives of Env. 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WATER

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THE PHILOSOPHY OF AUSTRALIAN WATER LEGISLATION PART 1 Sandford D. Clark SYNOPSIS

The English common laws inherited by A ustralia for both surface and ground waters are separately stated and their inapplicabi lity to Australian circumstances demonstrated. The contribution of the Gold Rush and of Alfred Deakin's Royal Commiss ion in the l 880's to the development of the Au stralian sys tem of administrative apport ionm e nt to natural resources are examined, as are the key legislative techniques for conferr ing supervising power on the State to contro l surface-water resources. The similar , but generally later, controls imposed on groundwater are exam ined and the reasons for a gradua l movement from merely controlling the construction of certain bores to the licens ing of extraction of water, and of drillers, are considered. Finally, the emergence of legis lation to control water quality is considered, with particular attention to the range of tech niques employed Âˇ by the legislatures of different States to compel the executive branch of government to co-ordi nate the activities of different government agencies . l. I. I

SURFACE WATERS The common law doctrine of riparian rights

The English common law rules concerning riparian rights developed to govern relations between those who, consistent with the laws of trespass, were. able to obtain access to surface st reams. These rights existed against other riparian owners, and could be asserted only by private rights of action . They thus depended on recourse to the courts through litigat ion . In outline, the riparian doctrine:(a) allowed persons owning land in latera l or vertical contact with a stream to use water for limited purposes, but denied its use to all other potential use rs; (b) only allowed water to be used on the riparian tenement and not on land which was not adjacent to the stream; (c) allowed any amount of water to be used for "ordinary" domestic a nd stock purposes; (d) allowed water to be used for other "extraordinary" purposes, but only if that water was subsequentl y returned to the stream "undiminished in quantity or quality"; (e) permitted a downstream riparian to obtain an injunction against any use by an upstream owner which offended the previous principles, whether or not the plantiff was actually injured by the upstream use. This right of action lay to protect the riparian ' s proprietary interest against the possibility that the upstream use might ripen into a prescriptive right through the doctrine of adverse possession, but left open the possibility of a barren assertion of right in the absence of any actual damage being shown to exist. There were, of course , limited stat utory incursions into this principle by the appointment of local commissioners for water supply and statutory cana l undertakings, which were governed by special Acts of Parliaments. Much of this legislation was sparked by the industrial revolution but was not relevant to conditions of English agriculture. In the sequestered villages of England, the water problems which seemed to create the greatest passion, then as now, were those concern ing the rights to fish in streams. The riparian doctrine was ideally suited to protect fishing rights, with its emphasis on limited use and access to streams.

The Author, Harrison Moore, is Professor of Law at the University of Melbourne. This paper was presented by Professor Clark at the A WWA Summer School in Adelaide, in February. Parts 2 and 3 of the paper will appear in subsequent issues of 'Water'. 16

1.2

The riparian doctrine and the Austra lian environment

1.2. 1 The physical requirements of irrigation Manifestly, the riparian doctri ne was inadequate to accomplish th e plans for extensive development of irrigation which ultimately fired imagin ation in A ustralia. Almost every aspect of it was offensive. To make irrigation viable, access to water would be needed by persons who were not riparian oweners; water would have to be used on propert ies which were not adjacent to streams; consumptive use of water in large amount s would have to be possible, without the obligation that it be returned to the stream; and it was inconceivab le that a downstream proprietor should be ab le to prevent an upstream irrigator, merely because the water was not returned to the river. Yet the physical inapplicability of the ripa rian doctrine to irrigation in arid areas does not, of itself, explain the legi slative structure which ultimately emerged in Australia . 1.2.2

The Gold Rush The Rush to the Victorian goldfield s in the 1850's, coming, as it did, immediately after the separation of Victoria from New South Wales, ultimately had important consequences for the shape of Australian water legislation. The fledgling Victorian Government was, for the first time, in a position to raise revenue, primarly through the alienation of Crown lands and the close administration of mining rights. From the very begin ning, then, Government adopted the pose of grantor of rights to certain resources, and a tradition of official intervention in resource management was early established. Furthermore, the physical demands of mining led to limited incursions into the riparian doctrine . It was necessary to take water away from streams for sluicing the overburden of claims, and the rules that water could only be ' used on adjacent tenements, and that water must be returned undiminished in quantity and quality failed to meet local needs. Furthermore, the need to counter common problems of sludge abatement led to the formation of local statttory boards with certa in autonomous regulatory powers. In retrospect, it is easy to see how each of these developments ultimately helped to formulate the particular Australian approach to surface-water management.

1.2.3 The Californian experience In contrast, the Californian Gold Rush of 1849 had occurred in an atmosphere devoid of administrative regulation. Although the United States Government purchased California from Mex ico at the time of the Gold Rush, the Federal Government passed no law s applicab le to Cali fornia for eighteen yea rs. In the meantime, rights to land, minerals a nd water were totally controlled by local customs which developed among the miners and eventua lly took on the characteri stics of customary law. Although the riparian doctrine also nominally applied to California, its inapplicability to mining circumstances was immediately apparent. Accordingly, loca l custom developed the so-called "prior appropriation" doctrine whereby the right to take water was obtained by the simple expedient of posting a notice at the head of one's ditch and pursuing work on the proposed diversion works with reasonable expedition. Provided the water was ultimately put to a beneficial purpose , the appropriator gained a right to take the amo unt of water he had claimed and to use it on any land, or to sell it to others, with no obligation to return that water to the stream. The doctrine brought with it two possible difficulties. A claim depended on priority in time . Thus, in dry seasons, if the supWATER

â&#x20AC;˘

ply of the river were insufficient, an appropriator could assert a continued right to divert all the water he has claimed against any later user , but was subject to the need to satisfy the claim of all earlier appropriators. In order to achieve this balance, it was ultimately necessary for an appropriator to obtain a court order against all other appropriators on a river, in order to declare his right. While this was undoubtedly profitable to the legal profession, the process was expensive, uncertain and wasteful of time and effort. Nor was it always effective. Thus Elwood Mead reported a conversation with a Cali forn ian appropriator in 1901. When asked how he obta ined his right to water, he answered: "First I got a court decree, then I shipped in two men from Arizona who were handy with a gun. " 1 1.3

jurisdiction under the central office as shall guarantee the preservation of water-courses and other sources and other sources of supply. (5) Power should be given to holders of water-rights to obtain easements over private lands on payment of compensation and proof that the route asked for by them has been selected for sufficient reasons ... (6) In Cali forn ia it is a lso held that, to prevent all irrigation from necessarily falling into the hands of capitalists, or any scheme for the genera l benefit from being negatived by one or two refractory landowners, there should be a means of organising irrigation areas and creating corporations for them, who should be capable, at the bidding of a majority of those interested, of doing a ll things necessary to the construction of works and distribution of water, by means of funds borrowed upon the common security. Here, again, the State officers would be employed in protecting the public interest and testing the plans of projectors . " 2 In these propositions, we can see the genesC of the Australian scheme. In Deakin's mind, Australian legislation should pro vide: (a) supervening rights for the State to control the use inade of river water; (b) power for the State to grant rights to individual water users and to supervise their use through local State employees; (c) certain limited powers for landowners to obtain court orders against their neighbours in order to transport water to, or from their land across the land of their neighbours; 3 (d) means of organising local trusts, with the approval of the majority of local landowners, which could raise money for, and administer, local distribution work .

Alfred Deakin and the Victorian Royal Commission into Irrigation

The Victorian Gold Rush had one further impact on the ultimate development of Australian water legislation. During the 1860's, Victoria experienced a run of unu sually good seasons. Disappointed miners turned away from the goldfields and joined another minor Rush to se ttle land for agricultural purposes in outlying district s of Victoria . With the return of more typical seasons, the countryside reverted to its more pastoral characterist ics and political pressure emerged to develop schemes for more permanent water supplies. Grand canal schemes were mooted and a Water Co nservation Act passed in 1883 to develop water suppli es in country areas. At much the same time, Alfred Deakin was appointed to conduct a Royal Commission into Irrigation. He approached this task with customary thoroughness, surveying and reporting on European, North African anrt American irrigation. It was the Cali forn ian experience which seems to have affected him most greatly. His ultimate recommendations were partly a response to the evi ls which he perceived in the Californian "prior appropriation" doctrine but were also un doubtedly influenced by the role which Government had already arrogated to itself in the development and apportionment of Victoria's resources. In hi s first Progress Report of 1885, Deakin recommended as follows: "Though there are lessons in American experience, already referred to, which have convinced the leading politicians of the States interested in that certain legislative and administrative duty should be undertaken by the Government, there is nothing either in their policy nor in their experience which casts any direct light upon the problem whether the States should assume any other att itide towards the man who increases the natural production and his own wealth by irrigating than its assumes towards the man who accomplishes the same results by reclaim ing or clearing his land, The conclu sions as to State act ion which have been accepted among so self-reliant a people would be worthy of attention if it were only because of the national tendency to which, in a measure, they run counter. Though they have been alluded to before, they are of so much moment that they will bear repetition, more especially as, if now called upon to offer suggestions as to the duty of the State towards irrigation, I cou ld find firm foothold in American precedent for just the recommendation which would be made by the irrigators of Colorado or California. Their verdict, based in the first five instances upon a practical trial in one or other of the irrigating States of the course advised is: (1) It is essential that the State sho uld exercise the supreme control of ownership over all rivers, lakes, streams, and sources of water suppl y, except springs rising upon private lands. (2) That it should dispose of the water to those desiring to irrigat e, on such term s and conditions and to such an extent as may be determined by professional or qualified officers of its own, its object being to encourage the greatest possible utilisation of the water on the largest possible area. (3) To ensure this, it should estab li sh the sca le of water measurement, and insist upon its employment in all transactions relating to water. (4) The State should appoint local water-masters to supervise the distribution of water, settle disputes, and exercise such WATER

1.4

1.4.1

The Australian system of administrative rights to water

The vesting of control in the State Deakin had recommended that the "supreme contro l of ownership" of water be given to the State. Had this proposal been implemented, it would have been true to suggest, as is sometimes done, that water was "nationalised" in Victoria by the Irrigation Act 1886. In fact, the original Bill which attempted to give the State the ownership of surface water, was greeted with scorn by lawyers in the Victorian Parliament. The eminent Ii>r. Quick, subsequently one of the first authoritative commentators on the Australian Constitution, greeted the Bill with the remark that "Such miserable and comtemptible literary productions would disgrace a shire council of TimbuftoO. " 4 As a lawyer, his primary objection could have been the legal point that the common law had remained true to the old Roman law principle that flowing water belonged to the " negative community" and was owned, neither by individuals nor by the crown. Indeed, its transient and elusive characteristics denied in the usual attributes of property. Yet, in order to confer sufficient adm in stra ti ve power on the State, it was not lo gically necessary to make the Crown the owner of all water - merely to ensure that it had supervis ing powers to control the use made of it. This point is fundamental to an understanding of the Australian st ructure of legislation. Whereas European systems under the Civi l law, with typical analytical purity, assert that everything must be "owned" by someone, and therefore induced a doctrine of the "public domain " and a special category of inalienable and imprescriptible "administrative property" to explain the way in which the State holds such resourcPs as major rivers on behalf of the public, the Australian legislation has generally by-passed such theoretical problems and concentrated on the task of conferring adeq uate power on State instrumentalities. In other words, just as the State is given power by statute to prevent me from building houses on flood-prone land, or building a factory in a residential area, so it may be given power to contro l the amount of water I take from a stream, or the use I make of it. In the first case, it is not necessary that the State sho uld become the owner of my land in order to control the way I use it. In the latter, it need not own the water. The formula, in its refined form, appeared in the Victorian 17

Water Act 1905, which pro vided that ''The right to the use and flow and to the contro l o f the water at any time in any river, creek, stream or water-course" shall vest in the C rown. A very similar ves ting section s was adopted in New South Wales, Queensland and Western Australia/although South Australia, out of abundant caution , declared that the Crown had the property in, and the right to the use and flow and to the control of the water in declared water-courses. 6 I am happ y to report that, consistent with fashion, South Australia no longer sees the need to wear both belt and braces and, in that splendidly modern and comprehensive piece of legislation, the Water Resources Act 1976, the C rown in the right of South Australia no longer asserts ownership over water. That a socialist Government should thu s conscious ly give up State ownership of water m ay seem anachronistic. In fact, however, this amply demonstrates that adequate control s may be exercised over a resource without reso rting to the confusing priva te law doctrines of ownership. 1.4.2

The power to declare water-courses The ves ting section is backed up in several ways . Disputes can, and do ari se, as to whether certain sources of water are subj ect to the legislation and, consequently, whether a landowner need s to obtain authority from the relevant State instrumentalâ&#x20AC;˘ity to use such water . In some States, such di sp utes are largely elimin ated by a provision which allows an Order-in-Council to declare that a certa in source of water is a water-course to which the Act implies. Effectively, then, this allows the executive branch to decide what natur.a l waters are to fall under the umbrella of the Act, and what waters are to be exempted from control. Such a feature does allow for desirable flexibi lity and, if we presume benign administration, is manifestly sensible . A simila r technique o f legislation has becom e characteristic of legislation concerning water quality. But, in an age of overwhelming bureaucracy, there is some judicial co ncern that such provisions delegate from the legislature to th e executive, important decisions about the depriva tion of individual propri etary rights. 1 shall revert to this problem subsequentl y when discu ss ing legislation concerning water quality.

1.4.3

The reservation of bed and banks The original instruction s of the Sout h Austra lian Commissioners to Colonel Light included the requirement that he reserve a st rip of land to the Crown along both banks of the whole length of the River Murray. Recalling th e riparian doctrine , it is apparent that the impact of such a prac tice would have been to prevent anyone but the Crown becoming a riparian proprietor. Landowners wou ld thus ha ve lacked the necessary sta tus to assert any common law rights to use water and , by this simple expedient, the Crown would have retained absolute rights to control the water . Elsewhere, as in Victoria, an informal practice of reserving to the Crown the bed and banks of certain rivers grew up and was later legislatively confirmed . 7 Unfortunately , however, Colonel Light did not execute his instruction s perfectly; and the legislation typically only app li es in relation to streams which form part of the boundary between allotments. Although th e reservation of bed and banks to the Crown, if universally adopted, would have co nferred all necessary supervening rights on th e State, the practice has only bee n selectively applied .

1.4.4 The abolition of prescrip tive acquisition of rights It was earlier pointed out that a downstream riparian owner could enjoin the activities of an up stream riparian for any technical infringement of his riparian entitlement, even though the down st ream owner suffered no actual damage. This right of action existed to guard against the possibility that a continued right to use water in excess of entitlement might be obtained by prescription . This potential abuse was remedied by a provision which stated that no presc riptive rights to the use of water could henceforth be obtained by adverse possession . 8 18

Such sect ions were obviously framed in days when problems of water quality were unknown. Although they prevent the acquisition of a right to use water by prescriptiOfl, they do not address the possibili ty that a prescriptive right to pollute water might also be obtained by an upstream owner.

1.4.5 The survival of private riparian rights As prev iously mention ed, the practice of reserving bed and banks to the Crown has not been universal. Where landowners thus do ow n land in lateral or vertical contact with rivers, the question arises whether, as riparian proprietors, they continue to enjoy any common law rights, or to enjoy their neighbour's use, or whether th ese pri vate rights of action have necessar il y been abolished by the superveni ng right s given to the State. 9 It is not certain that Deak in saw considerable evils in the American sys tem of judicial apportionment of rights and wou ld have so ught to di scourage litigation. Indeed , one of the most rema rkable feat ures of Australian water law is that a resource so vital to our history and development should have attracted so little litiga tion. When th e question of surviving riparian right s first came before the courts, it was held that the very purpose of the vesting section in the New South Wa les Act was to take away all private ri ghts of action . But the better view seems now to be that the vest ing section: "does not directly affect any private rights, but gives to th e Crown new rights - not riparian rights - which are superior to, and may be exercised in derogat ion of, private riparian rights, but that, until those new and superior rights are exercised , private rights can and do coexist with them." 10 The propos iti on is thus simple. Private rights of action against one's neig hbour continu e to exist, bu t only to th e extent tha t their continued existence is not necessar ily inconsistent with the way the State has chose n to exercise its regulatory powers. Yet the application of the principle proves more difficult, as it may be hard to tell what constitutes an "exercise" of power by the State, and what amount s to " necessary inconsistency " . There may also be problems about how far the private right abates; while the necessary in co nsistency may deprive a plantiff of an effective remedy by way of damages or injunction , the substantive right to sue may st ill exist and may, perhaps , be asserted for nuisa nce-value alone. While it is difficult to apply the principle with certainty, if a private diverter were authorised by li cence to take water in a particular amount fo r a particular purpose, the mere existence of that licence would seem to be ne'tessarily incon sistent with_ any contrary assertion of a downstream rip a ria n right. If, on the other ha nd , the amount diverted exceeded the entitlement in the licence, or water were put to a use which was both unauthorised by the lice nce and not permitted at common law, there seem s to be no reason why a priv a te right of action should not lie if the common law allows it. It is thus apparent that one must be careful of assertions that Australian legislation ha s nationalised water and abolished th e ripa rian ri gh t. This is not true in fact. Although liti gation , to the extent that it became necessary in the western states of America, may have been a bad thing, it can still serve a useful adjunct to pub li c administration of a resource. 1.4.6 Irrigation Trusts and Central Government The fina l element in Deakin's proposal was the possibility that landowners in a particular area might ban together in mutual self-interest, to form a Trust and to construct and maintain their own diversion and d ist ribution works, built from moneys raised aga inst the sec urity of rates to be levied on all lands commanded by those works . Legislation did not ass ume that major headwork s could be built in this way, but local autonomy and responsibility was encouraged. Thus, at the same time as the Victorian Irrigation Act 1886 was passed, the Waterworks Encouragement Act 1886 was also enacted . Its purpose was to grant concessions to the Chaffey Brothers, whom Deak in had lured from Southern California to esta blish an irrigation settlement at Mildura.

Continued on page 28 WATER

'SIROFLOC' -A NEW WATER CLARIFICATION TECHNIQUE A. J. Priestley and P. R. Nadebaum INTRODUCTION A problem that faces many Australian townships is the supply of a high quality potable water su itab le for domestic or industrial use. In many cases the water availab le to the municipality contains significant levels of colour a nd turbidity , whi ch can not only interfere with disinfection by chl orin ation , but can also lead to the formation of significa nt levels of chl orinated organics (haloforms). To avoid these prob lems t he water can be treated to remove the colour. t urbidity and a ny other objectionable materials before chlorination and distrib ution . Water treatment , as an engineering art, dates back to antiquity. In the fir st century AD, Roman engineers discovered the coagulating powers of "alum inous earth " a nd developed water distribution systems to a high level. However, it was not until early in the nineteenth century that the first slow sand fi lter was com missioned in Scotland to clarify a turb id feed water. Si nce that time the conventional process of chemical Âˇfloccul ation , followed by clarification a nd fi ltration , has been continuously refined. However , at the present time, the processes in volved are still relatively slow a nd large equ ipm ent volumes are req uired resulting in re latively high capital costs. In I 976 CSIRO estim ated that on present costs u p to $500 million wi ll be req uired over the next twenty years to finance new water treatment fac ilities. T his will occ ur during a period of increasing capital shortage , and public utilities will be very conscious of capital costs (Fisher, 1977) . At CSIRO a research program has been underway since 1976 with the aim of developing a faster, cheaper water clarification technique. Thi s resu lted in the invention a nd development of the Sirofloc process (Kola ri k et al., 1977).

Hydrolysis of an arb itrary metal oxide can be described by equation 1. T his reaction occ urs favo urably under alk aline conditions to produce a highly hydroxylated surface. A charge can then be developed by the add ition of acid or alkali as shown in equations 2 and 3. Under acidic conditions the surface is positively charged a nd a ny negatively charged coll oids in solution should be attracted to the magnetite surface. W hen t he pH level is raised above 7, the surface becomes increasingly nega tively charged and any attached colloid s should be repell ed. Conseq uently, the magnetite should act as a coagulant/adsorbent at low pH and be capab le of regeneration at hi gh pH. T his simplified picture is complicated by t he presence of hardness and / or second ary coagula nts such as polyelectrolytes. T hi s will be referred to in a later section . A sim ple block diagram illustrating the major steps in the Sirofloc process is given in Figure 1.

Conlod slurry and Coagulant

Con tad

wal u and Hydro"y,nag

Sol 1d/ L1qu1d Separation

Loadt d

Hydroxymag Sol1d / L1qu1d 5t parat ion

Wo, h

Hyd ro.r yma9

Solid / L1qu 1d Scporat1on

Conloct

Hydroâ&#x20AC;˘yma9 w,l h IH HaOH

liquid EUlu t nl

I Figure 1: Sirofloc Process block diagram

PROCESS DESCRIPTION Essenti ally, t he Sirofloc process is a technique for the removal of coll oid al colour and turbidity from a raw water. However, it can also remove dissolved iron , manganese, bacteria, virus and, under specific conditions, heavy meta ls. The process is based on addition to the raw water of a fine ly divided magnetite slurry (particle size range 1-10 um) whi ch has been pretreated with caustic soda. T he ca ustic soda treatment produces a reversible charge on the magnetite surface and thi s ca n interact with charged coll oids in solution . Equations 1 to 3 illustrate in a simple way how the charge is prod uced and controlled.

/o, '\.

M _

OH I

H-OH....- _M _O

M-

(1)

(2)

(3)

Dr Tony Priestley, a Senior R esearch Scientist with the CS/RO Divisio.'l of Chemical Technology, South Melbourne, is the member of th e CS/RO team responsible for the chemical engineering aspects of Sirofloc. Dr Peter Nadebaum is a senior process engineer with Davy McKee Pacific Pty Ltd, a partner in AUSTEP, which is involved in the engineering and commercial developm ent of the process. This paper is a resume of two much more detailed papers presented at the A WWA 's 8th Federal Convention in Queensland (see Anderson et al., 1979 and Nadebaum and Ng uyen, 1979). WATER

Initially, t he feed water pH level is adjusted to the optimum value for the process. This can vary from 5.0 to as high as 8.5 depending on the particu lar water although , in general, the lower the pH the better the perfor mance . Subseq uently, t he water is dosed with freshly regenerated magnetite slurry at a rate which can vary from 0.5 to 2.0 % v Iv of the raw water flow . The magnetite must be derpagnetized before add ition , as otherwise it clumps together and does not present its full surface area to the water. The first stage contact time between water and magnetite can vary fro m 5 to 10 min. d uring which colour bodies in the water (mainly humic and fu lvic acids) a re destabilized and adsorbed on to t he magnetite surface. T here is also some red uction of turbidity. Prior to t he second stage a polyelectrolyte is dosed at a rate which can vary from 0.1 to 2.0 mg/L , this being mainly dependent on the level of t urbidity in the raw water. D ur ing the second stage, which can vary in length from 2 to 4 min., fina l traces of colour are removed and the, polyelectrolyte firml y binds the remaining turbidity on to the magnetite surface . Total contact time in the process can vary from 7 to 14 min. The contact stages a re followed by separation of the magnetite from the clarified water which now has a turbidity generally less than 1 NTU a nd colour less than 5 Pt-Co units. The magnetite is then cleaned and regenerated prior to reuse , and it is this step which makes the process uniq ue. Magnetite has been used before in water treatment but only as a floe weighting agent a nd on a once-through basis. T he magnetite used in the process , after regeneration with caustic soda , acts as a coagulant in its own right and can eliminate the req uireme nt for conventional coagulants such as alum or ferric chlorid e. In regeneration there are two differenfphenomena occurring. Firstly, the turbidity and colour bodies are stripped off and separated from t he magnetite, and secondly the surface of the magnetite is reactivated. Reactivation requires a pH level in the range 11 -12, while t he was hing step requires a pH level of b etween 10 a nd 11.

PROCESS DEVELOPMENT AND PILOT PLANT OPERATION T he development of the process from a simple jar test to a fully 19

Figure 3: Flocculation tanks

continuous pilot pl an t occurred during the years 1977 to 1978, and is described in detail in a paper delivered at the 8th Federal Convention of the AW AA, (Anderson et al., 1979) . The final flow diagram adopted for the pilot plant is illustrated in Figure 2. Q• I unit of Flow !i -ro wrn Cont1Jt1

Cla r1fieci Water

w1 t!J Vigorous

{ !OOQ }

Aq 1tation 1010. Dose

lit::1dro\i,mc9 ( t Q ' , - - - - - ~ = ~ =~ ~

To Re. ove r':!

separated from the treated water simply by magnetizing it and allowing it to settle rapidly in a clar ifier. Upflow rates of up to 10 m/ hr cou ld be obta ined with magnetite carryover rates of around + mg/ L. If this is followed by a 2 hr . holding tim e in a clear water tank the magnetite level in th e product water will be less than 0 .5 mg/ L. As can be seen from Figure 2 regeneration of the magnetite in the pilot plant involved a more complex arrangement than indicated in the simpl e block diagram of Figure 1. In order to reduce both the washwater and caustic soda requirements to a minimum , the washing process utilized the principle of countercurrent fl ow while the high pH react ivation step was achieved with a thick magnetite slu rry containing little supernatant liquid. The process illustrated in Figure 2 consists essenti ally of a three-stage countercurrent decantation process with a thkk slurry ph ase reactivation step pl aced in between two washing steps . The reactivation step was placed in this intermed iate position in ord er to minimize the pH of the regeneration efflu ent and consequently ca ustic soda consumption . Approximately four volumes of washwater are req uired per volum e of full y settled magnetite slurry, which means that the washwater volume can vary from 3% to 6%-of the total plant throughput depending on the dose of magnetite required. However , research work currently und erway is pointing to a way of reducing this figure to less than I %. T he selection of equipment for the solid /l iquid separation step proved to be crucial to th e success of the regeneration process . At each stage it was important to achieve an efficient separation between the magnetite and the colloidal materi al washed off the magnetite surface. This could not be achieved with simple settling tanks or a countercurrent flow column , but magnetic drum separators proved to be id eal fo r the app lication. In fact such separators have been used for many years in the coal washing industry to recover and clean mag netite used in heavy med ia separat ion circuits. Beca use of their wide pilot plant ex perien ce, the Australian Mineral Development Laboratories (AMDEL) were contracted by CSIRO to constru ct a Si rofl oc pilot pl ant capab le of treating up to 0.14 ML/day. This plant, which is based on the design described above, is illustrated in Figures 3 a nd 4. After it was com missioned in Adelaide the plant was transferred to the Mirrabooka Treatment Works of the Perth Water Board where it was to treat a highly colou red anaerobic groundwater. The raw water properties are tabu lated in Table 1.

OC • Oema9ne115in9 Coil f' M • Ftoccu lotm9 Magnet

'9' •

TABLE 1.

MIRRABOOKA RAW WATER QUALITY

Sohd/Lrqu1d Se pa rouon

Figure 2: Process flow diagram

For the coagu lation/ fl occ ul ation step a series of four stirred tanks with controlled agitation rates was found to be a satisfactory means of contacting the water with the magnetite , while the magnetite was

Turbidity NTU

Colour Pt-Co. c. u.

Fe (sol.)

5-20

60-100

1-2

mg / L 1-2

This water is quite difficult to treat by the conventional process and it was predicted that it would present a signifii!ant challenge to the pilot plant. T his proved to be the case, and six months of intensive experimentation were required before the pilot plant could consistently produce a good quality produ ct water at an economic price. Two important factors in this achievement were the adoption of a two-stage countercurrent flow process for the coagulation / flocculation step and the choice of a polyelectrolyte which worked well at a higher pH ( > 6). With the two-stage countercurrent flow process , illustrated in Figure 5, Stage Z

PROOUCT

WAHR RAW W-'TfR

- - Waftr

- - -

Ma911el1te Slurr~

Figure 5: Two stage countercurrent process

Figure 4: Regeneration train

lower colour leve ls were achievable at a reduced magnetite dose . This produced savings in operating costs compared to a single-stage process without signifi cantly changing capital costs. The cost of the extra clarifier is offset by the reduced size of the regeneration train. With the right choice of polyelectrolyte, good turbidity removal could be achieved at the natural pH of the raw water (6.2) , again reducing operating costs. WATER

APPLICABILITY TO OTHER WATERS One of the major achievements of the pilot plant operation, apart from prod ucing a good quality water , was that it demonstrated that results obtained in jar tests cou ld be reproduced or even bettered in a continuously operating plant. This meant that the applicability of the Âˇ process to other waters could be proved by simple jar tests rather than an expensive and time-consuming pilot plant operation. Successful jar tests have been carried out on a wide range of different waters and a sampl e of the results obtained is given in Tab le 2. TABLE 2.

JAR TEST RESULTS

YARRA RIVER, VICTORIA T(NTU) 20-250 Raw water 1-5 Alum alone Magnetite & P .E . < I

C (pt-Co.) 50-150 5-20 0-10

Fe (mg/ L) 0.1-0.3 0.1 _< 0.1

WANNAROO WELL 24, PERTH , WESTERN AUSTRALIA T (NTU) C (pt-Co .) Fe (mg/ L) 1.1 35 0.50 Raw water 3.0 20 0.84 Alum alone 1.1 <5 0.05 Magnetite alone

pH 7.0 5.5-6.0 4-5

pH 6.2 5.5 6.0

HAPPY VALLEY RESERVOIR , SOUTH AUSTRALIA T (NTU) C (pt-Co .) pH Raw water Alum alone (10 mg/ L) Magnetite + alum (10 mg/ L) Magnetite + P.E. (0.5 mg/ L)

5.0 4.7

35 30

8.5 7.7

1.3

7.5

8.0

1.0

7.5

8.4

The waters treated covered a range of different types, e.g. high turbidity and colour - Yarra River; low turbidity and high colour Wannaroo and Mirrabooka; highly alkaline waters - Happy Valley Reservoir. Resu lts indicate that the polyelectrolyte dose was controlled mainly by the level of turbidity whi le colour largely determined the magnetite dose. In the case of highly alkaline waters it was fo und possib le to operate at a much higher pH level of 8.4 thus avoiding excess ive doses of acid or al um . EFFLUENT TREATMENT AND DISPOSAL The effluent from the process consists of a turbid and highly coloured water which contains all the colloidal material origina lly in the raw water plus a small amount of salt (about 300-400 mg/ L). The volume of this effl uent depends on the level of magnetite dose and can vary from 3% to 6% of the tota l raw water flow , a typical valu e being about 4%. There are various options for the treatment and / or disposal of this effluent which depend somewhat on the site location . Two of the simpl est options are direct groundwater recharge or crop irrigation after adjustment of pH and the sodi um adsorption ratio. However, these depend on a suitab le site being available and are not universal solution s. Discharge to sewer may also be possible at some sites, especially where problems are encountered with H2 S production in the sewer. The effluent can be treated with alum to produce a clear effluent of moderate colour which can be successfully reused as washwater. If alum sludge is available from a conventional plant this can be used in lieu of fresh alum with little addition to the total sludge volume. Alum treatment of the effluent prior to reuse has been successfu lly demonstrated on the pilot pl a nt scale at Mirrabooka . The alum dose required is about 25% of that used in the conventional process. COMMERCIAL SCALE PLANT DESIGN AND PROCESS ECONOMICS The successful operation of the pilot plant at Mirrabooka opened up the way for furth er development of the process to a commercial scale. Toward s this end the process was licensed early in 1978 to Davy McKee Pacific Pty. Ltd. and !CI (Aust) Pty . Ltd. However, in 1979 the Commonwealth Department of Productivity agreed to provide finance for demonstration plants for severa l new water treatment technologies developed by CSIRO under the national interest provisions of the Industrial Research and Development Incentives Act. A joint venture, WATER

AUSTEP , was formed by Davy McKee Pacific Pty. Ltd. and J.O . Clough and Son Pty. Ltd. to build the demonstration plants and to commercially market the various processes. The demonstration plant for the Sirofloc process is being built at Mirrabooka and will have a capacity of35 ML/day. The plant has been scaled up directly from the pilot plant and uses the same type of conventional commercially available equipment. It should be commissioned in August 1980. Data for the design of a commercial scale plant can be collected from both jar tests and pilot plant operation (Nadebaum and Nguyen, 1979). Because of the simplicity and low cost of jar tests it is desirable to coll ect as much data as possib le by this technique. Magnetite dose, contact pH, acid dose (if any), contact time, type and dose of polyelectrolyte required, can all be determined from such tests, although some care may be required with the mixing conditions after polyelectrolyte addition. With some polyelectrolytes the floes are sensitive to high shear situations and careful sealing up of the stirrer is required to avoid cond itions which cou ld lead to inefficient turbidity removal. '"' Sufficient data can generally be obtained from jar testing alone for the satisfactory desig n of small ( < 20 ML/day) Sirofloc plants . However, for plants of large size and capital cost a more precise determination of certain factors by pi lot plant work is desirab le. These factors are I ox idizing agents , are they required and , ifso, what dosage level? 2 ca ustic soda consumption in regeneration. 3 was hwater requirement . 4 final clarifier uptlow rate which gives acceptable magnetite carryover rate. S process co nfi guration , sin gle or two stage? Simple jar test techniques are presently being developed to es timate these parameters , and these estimates should improve as wider experience is obta in ed . The need for an oxidizin g agent was a particular requirement of the Mirrabooka situation where the raw water contains significant levels of H2 S. Initial jar tests gave misleadin g results on the amount of oxidant and reaction time required as some degree of oxidation occurred during sampling and transfer of the raw water to the laboratory. Operation of a continuou s pilot plant also gives valuable information on the long-term behaviour of the process , especially with regard to meeting the product water quality specifications with a varying raw water qua lity. It can also be used to train plant operators. The main purpose of the demonstration plant presently under const ruction is to "de monstrate" the full scale' app lication of the Sirotloc process. Pilot testing has enabled the design and sizing of the major eq uipment items to be carried out; operation of the demonstration plant will afford verification and improvements in precision of the eq uipm ent design procetlures, and will also confirm that the va riou s treatment processes involved can be carried out in eq uipm ent of larger scale, and that the desired water quality spec ifications can be achieved. The plant wi ll also serve to demonstrate fully automatic control of the process; this was not feasible at the pilot plant scale because of the relat ively hi gh cost of equipping the pilot plant to operate automatica ll y. The capital and operating costs of the Sirofloc process depend on the qu ality of the raw water being treated, and comparison with the conventional process will have to be on a water by water basis. The construction of the demonstration plant has provided detailed construction costs for a large Sirofloc plant (Nadebaum and Nguyen , 1979) and Table 3 gives typical capital costs associated with a 35 ML/day Sirotloc plant for two different raw waters. The raw water qua li ty param eters and the process operating parameters for the two cases are given in Tables 4 and 5. T able 3 illustrates that cap ital costs of a Sirofloc plant can vary cons iderab ly depending on the ease of treatment. Costs associated with the regeneration plant make up about 50% of the total cost, and it is desirab le to keep the magnet ite dose as low as possible . However, it is predicted that with an efficient process design Sirofloc capital costs cou ld be around 30 % lower than those for a conventional water treatment plant. Very recent development work has lead to a significant simplificat ion of the regeneration plant, and this promises significant further savings in capital costs. Prediction of operating costs is more difficult, but experience from the pi lot plant indicates that for the Mirrabooka situation they will be about the same as the conventional process (Anderson et al., I 979).

TABLE 3. TYPICAL LEVELS OF CAPITAL COST ASSOCIATED WITH A 35 ML/DAY SIROFLOC PLANT FOR THE TWO EXAMPLE CASES, AT THE PRESENT ST AGE OF DEVELOPMENT CASE A (Anaerobic Groundwater)

CASE 8 (Surface Water)

$633,000

$422,(XX)

REGENERATION PLANT (INSTALLED) Including: -mechanical equipment -building -piping and pipebridge -chemical dosing -associated electrics, $666,000 instruments and site works

$527,(XX)

CONTACT PLANT (INSTALLED) Including: - clarifier(s) -con tact tanks -chemical dosing equipment -associated pumps, piping, electrics, instruments and site works

COMMON PLANT Including: .:....control room -raw water and product water undergro und piping -roads and drains -landscaping

TABLE 5. VARIATIONS IN smOFLOC TREATMENT PLANT ASSOCIATED WITH THE TWO EXAMPLE CASES

$197,000

TOTAL 35 ML/ DAY INSTALLED PLANT COST

$1,496,000

$197,(XX) $1,146,(XX)

THE FUTURE While the next step in the commercia l development of the process is the com miss ioning of the demonstration plant, research work is continuing into ways of improving and sim plifying the process . Cons id erab le work is being und ertaken into the effect of various cat ions and an ions on the magnetite particles. It has been found that the presence of Ca + + or Mg + + can a lter the surface charge on the magnetite such that it remains positive at all levels of pH normally encountered. Consequently, effic ient clarification of hard alkaline waters can be achieved at pH levels as high as 8 and 9. Adsorbed hardness ions interfere with magnetite regeneration but they can be easi ly desorbed prior to regeneration with a simple one-stage wash with raw water at pH 6. Some anions a lso adsorb on the magnetite surface, and removal of phosphate ions from both potable and waste waters has been noted in laboratory jar tests. The adsorption of polyelectrolytes on to the magnetite surface can a lso change t he nature of the surface charge, and the effect of different polymer structures on the surface charge during clarification and regeneration is being investigated. This work a ims to deli neate the TABLE 4.

WATER QUALITY PARAMETERS FOR THE TWO EXAMPLE CASES

RAW WATER Colour Turbidity TDS Fe Total hardness Total alkalinity

(Pt.-Co.) (FTU) (mg/ L) (mg/ L) (mg/ L as CaC03) (mg/ L as CaC0 3) (mg/ L)

pH PRODUCT WATER Colour Turbidity Iron (soluble) 22

polymer structure which wi ll optimize the process performance in both clarification and regeneration. Another area of current research is aimed lit simplifying the regeneration process. As illustrated in Table 3 this is a cost sensitive area dependent on the magnetite dose level. Also, in its present form , the regeneration process is too complicated for small scale plants ( < 10 ML/day) . A new process scheme, which is currently being investigated in the laboratory, promises to simplify significantly the regeneration process and redu ce the washwater req uirement to less t han 1% of the plant t hroughout. Biodegradation of the effluent with specia ll y selected bacteria is also being investigated. Unti l now most appl ications of the Sirofloc process have been in the treatment of municipa l water supplies; however , CS IRO is presently seek in g wider applications. The treatment of industria l waters prior to reuse is one such example and successful jar tests have been carried out on effluents from both the steel and paper indu stries. In years to come in some drier parts of the country the reuse of water from secondary sewage treatment plants will be seriously considered, and Sirofloc could find application here as a tertiary treatment technique. It is hoped that the intensive research effort at present underway into the physica l chemistry of the magnetite surface and its interaction with the env ironment will lead to both a simp lification of the existing process and a broadening of its area of application .

(Pt-Co.) (FTU) (mg/ L)

CASE A (Anaerobic Groundwater)

CASE 8 (Surface Water)

90 5-100 300 2

40 5-20 60 1

30 2 6.2

12 6.8

0-7 0-1 0-0.05

0-5 0-1 0-0 .05

(a) CONTACT PLANT Number of contact stages Number of clarifiers Contact time (min) Pretreatment with oxidant (b) MAGNETITE REGENERATION PLANT SIZING Magnetite flowrat e (as 0/o w/ w dry magnetite/ raw wa ter) Washwater flowrate (as 0/o of plant throughout)

CASE A (Anaerobic Groundwater)

CASEB (Surface Water)

2 2 12

I I

yes

20/o

1.250/o

6"7o

40/o

ACKNOWLEDGEMENTS The Perth Water Board made a major contribution to the success of the pilot plant. They provided not only a site and a bui ldi ng to house the plant , but also on-site facilities, maintena nce and operating personnel, and a major financial contributi~n. REFERENCES ANDERSON, N . J. , BLESING , N. V., BOLTO, B. A., KOLARIK, L. 0., PRIESTLEY A. J. and RAPER, W. G. C. (1979) . The Sirofloc process for t urb idity and colou r remova l: Process development and pilot plant operation. Proceedings of the 8th Federal Convention of AWWA, 1-17. FISHER, N. W. F. (1977). Capital funds for water: Prospects and policies. Proceedings of the 7t h Federal Convention of AWW A, 623-637. KOLARIK, L. 0. , PRIESTELY , A. J. and WEISS, D. E. (1977). The Sirofloc process for turbidity and colour removal. Proceedings of the 7th Federal Convention of A WW A, 143-160. NADEBAUM, P.R . and NGUYEN, H. V. (1979). The Sirofloc process for turbidity and colour remova l: Commercia l app lication. Proceed ings of the 8t h Federal Convention of A WW A, 213-227.

APOLOGY -

WE WERE CARELESS

weÂˇ apologise for the misprint in the June issue. The Author of the paper 'Water Qua lity of the Murray' is Mr. D. M. Coucouvinis. Editor. WATER

TOXICITY OF W ASTEW ATERS SOME GENERAL IMPLICATIONS W. D. Williams

Let us take a pragmatic approach by considering how the vario us possible toxic pollutants in wastewaters affect (degrade) the quality of inland waters used for various beneficial uses. The beneficial uses considered here are domestic water supply, agricultural usage, industrial use, and use by aquatic life and wildlife.

carbamate insectic ides which ha ve high mammalian toxicity by acting on the nervous sys tem . The clorophenoxy herbicides such as 2, 4-D and 2, 4, 5, -T, are not nearly as toxic to mammals, but other potential dangers are involved, namely teratogen icit y and embryonic toxicity. This is particularly so when herbicides are contaminated by dioxin which can induce foetal and maternal toxicity at levels as low as 0.0005 mg/ kg. Of toxic organic chemicals other than pesticides in wastewaters, PCBs (polychlorinated biphenyls) are perhaps par jcu larly worrying for it appears that they accumulate in fatty tissues and affect reproductive processes by increasing the activity of those li ver enzymes which degrade sex hormones. Phthalate esters, likewise, present a potential but large ly unknown hea lth hazard in water supplies. They have been implicated in growth retardation , accumulation, and chronic toxicity. Phenolic compounds principally affect the organoleptic properties of water supp lies, that is, they taint the water with undesirab le tastes and odours. Halomethanes, substances produced by the chlorination of water containing organic material, are yet another group of trace organics which are a potential threat to the safety to drinking waters. Of inorganic poisons, heavy metals are a major concern if present in domestic water supplies. Their effect on humans varies as a lso does their toxicity. Cadmium is one of the more toxic metals but its impor tance has been overlooked in the past becau se many of it s effects on man - hypertension, liver and kidney damage - can also be brought about by excessive consumption of alcohol and by cigarette smoking. Cadmium is retained cumulatively in the liver and kidney. Mercury is another highly toxic heavy metal pollutant and organic forms can produce illness after the ingestion of just a few milligrams. Often mercury poiso n ing is insidiou s in that it manifests it self long after exposure, in some cases many years later. The effect of mercury exposure can be difficult to determine as chronic effects are neurological and behavioural and th us difficult to diagnose. In summary, then, many wastewaters contain toxic sub stances, and if allowed to contaminate domestic water supplies, may adversely affect the healt h of man directly either by being toxic , carcinogenic, or teratogenic. There is clearly need for ca~tion in the discharge of wastewaters containing such substances becau se of the persistence of some, and the toxic nature of others. Also, they offer further problems: many a re difficult to detect, difficult to remove from wastewater effluents, and may themselves poison biological treatment mechanisms if they gain access to these by, for example, by public sewerage systems.

Domestic water supplies

Agricultural usage

In considering the effects of poisons on domestic water usage we approach the direct toxicological effect on man of poisons in wastewaters. Although the effects on humans of some commonly di scharged poisons are broadly known, for many there is a lack of deta iled knowledge of effects, particu lar ly effects of a long-term nature - such as carcinogenicity, foetal aberrat ions, foetal malformations, and chronic toxicity. In the area of pesticides, organochlorine compoun ds usually affect the nervous sys tem, but may affect other physiological systems adversely, and there are some experimental indications that they ma y have carcinogenic properties. They are not, however, notably toxic to man in a direct sense. This is not so fo r the organophosphorus and

Wastewaters containing toxic substances, when discharged into waters subseq uently used for agricultural purposes, may degrade this beneficial use in a number of obvious ways. They may, in particular, cause problem s in the usefulness of the supp lies for stock watering (here many of the comments made in relation to drinking water quality are equally applicable) or for irrigation. However, these problems should not be overemphasized for there are many examples in Australia where su itably treated wastewaters have been used directly and successfully for many years to maintain large numbers of pastoral animals. The Werribee farm in Victoria provides an example. Within an Australian context, a review of this important subject has recently been given by Strom (in press), and more details are given in the report prepared by Gutteridge, Hask in s and Davey (1976, 1977). The point to note here is that possibilities of wastewater reuse are impaired by the presence of toxicants.

INTRODUCTION The paper by Professor John Cairns in the March 1980 iss ue of this journal (Cairns, 1980) on the need for development of a toxicity testing capability for Austra lia, prompts the present article. In general, Cairns' approach is agreed with but, there is a real possibility that many non-biologist members of the A WWA may not be fully aware of the implicat ions of toxic discharges to the aquatic environment. The letter by A. P . Aitken in the same issue of 'Water' wou ld tend to support this view. The question which must arise from such members is not that of how a toxicity testing capabi lity should be developed but why such should be necessary. This brief paper endeavours to provide the answer to this question and to explain why the presence of toxic compounds in inland waters is of importance as is their detection and the assessment of their toxicit y.

THE GENERAL IMPACT The nature of the impact of the aquatic environment of poisons or toxic substances contained in wastewater is determined by many factors. One, of course, is the chemical structure of the poison. Others are concentration and dosage, exposure time, the prese nce of other poisons and solutes, the pH, temperature , salinity and oxygen concentration of the receiving water, and the nature of the aquatic biota involved . The technical assessment of the degree of effect, i.e. the toxicity, and the multiplicity of problems involved (e.g. syne rgism, antagoni sm ) , are not discussed here , but it is noted that Australian approaches to this matter leave much to be desired -as Cairns (1980) suggested. Whatever the factor s involved, the overall ecological effect of toxic discharge is generally to bring abo ut a decrease in both biological diversity and biomass. But matters are more serious than that simple statement may suggest: inland waters are used for drinking purposes, fish production, irrigation, recreation, wildfowl breeding, stock watering and so on, and all these uses can be adversely affected by toxicant discharge.

THE DEGRADATION OF BENEFICIAL USES

W. D. Williams is Professor of Zoology at the University of Adelaide, South Australia. This paper incorporates in part an address to a joint meeting of the A WWA and the Environmental Branch of the Institution of Engineers (Australia) in Melbourne (April 16th) on the subject of wastewater toxicity and its implications. WATER

Industrial usage Vast amounts of water are used in A ustralia and elsewhere for industrial purposes. The extent to which this water is impaired in

quality because of wastewater discharge varies according to the nature of the industrial use and the severity of wastewater pollution . Clearly, some industries have very low quality requirements, e.g. those needing water for cooling, some very high, as in the food industries. Modern waste treatment technology permits water of almost any quality to be treated to a desired level, but of course this entails a cos t. The provision of facilities to remove even simple substances (such as phosphates and nitrates) is not cheap by any standards. But the basic principle is quite straightforward: what one industry saves by discharging inadequately treated wastewater may well be payed by another to obtain water of desirable quality . Nevertheless, except for those industries in vo lv ed in the manufacture of food and drink, the presence of toxic substances in indu strial water is not as critical as in certain other beneficial uses. We should certainly be aware, however, of the potential problems.

Aquatic life and wildlife The maintenance of healthy ecosystems wherein aq uatic life and wildlife flourish is another recognized beneficial use of inland waters. Discharge of toxic wastewaters into such ecosystems places at risk their success ful maintenance in a number of ways. Two phenomena are of particular importance in determining the extent of the hazard: bioaccumulation and persistence. The salient point about bioaccumulation is that although ambient concentrations may be low (sometimes undet ectably low), plants and an imals accumu late and concentrate the substance involved within their bodies . Moreover, magn ifica tion of concentration may occur as the food chain is ascended. Ultimately, concentrations ca n b~ reached which are toxic to the organisms in vo lved or to man if he eats them. Fish and bird life are of the greatest concern in this respect since they occupy high trophic levels. The allied problem is that of persistence: many poisons are refractory to biodegradation and persist in the environment, e.g. heavy metals, PCBs. Study of such matters is not easy for food webs in the aquatic environment are often co mplex. Moreover, the fate of toxic substa nces in the environment is determined not on ly by biological processes but also by physical and chemical processes. The actual manner in which persistent or bioaccumlated toxic

substances exert their effect on the inhabitants of ecosystems is often subtle. They may reduce the viability of adults or juveniles, decrease grow th rates, adversely affect behaviour, or retluce reproductive capacity. The implications for man are several. The more obvious include the destruction of fishing and wildfow l resources, and the degradation of freshwater ecosystems useful as natural biological purification mechanisms (e.g. the River Murray) . But there are severa l less obvious implications. Perhaps the most important is that toxic wastewaters act as stressors of aq uatic ecosystems and this generally results in a reduced variety of species present, another aspect of man's continuing reduction of the overall diversity of the biosphere - a reduction with conseq uences yet to be fully determined but lik ely to be deleterious. In the lon g term the impact of toxic wastewaters may prove to have been the most significant of all for man depends for very survival upon the maintenance of a healthy viable and secure biosphere.

ACKNOWLEDGMENTS Dr. B. T. Hart , Caulfield In st itute of Technolocy, Dr. D. Kay, Mini stry for Conservation, Victoria, and Dr. P. S. Lake, Monash University, are thanked for comments on the draft of this paper and thanks to Mr. D. Lane, Engineering & Water Supply Department, South Australia for information provided.

REFERENCES CAIRNS, J. Jr. {1980). Developing a toxicity-testing capacity for Australia. Water 7( 1) :14-15.

GUTTERIDGE, HASKINS & DAVEY, Pty. Ltd. (1976). Planning for the Use of Sewage. Vol. 2. Report to the Bureau of Studies, Department of Environment. Housing and Community Development, Canberra. GUTTERIDGE, HASKINS & DA VEY, Pty. Ltd . (1977). Planning for the Use of Sewage. Summary Report. Australian Government Publishing Service, Canberra. STROM, A. G. (in press). Wastewater as a resource. In: W. D. WILLIAMS (Ed.) An Ecological Basis for Water Resource Management. Australian National University Press, Ca nberra.

WATER QUALITY MANAGEMENT ,OF STORAGE RESERVOIRS D. W. Lynch INTRODUCTION Pot ab le water supp lies genera lly must meet certain minimum requirements and the water: • must not be contami nated with pathogenic organisms; • mu st not contain concentrations of dissolved or suspended matter which wou ld be det ri menta l to human health; • should , as far as is practicab le, be palatab le and aesthetically acceptab le to the consumer in respect of taste , odour, colour and turbidity; • should be non-corrosive and not cause stains; and, • should be economica l for use by all the consumers. Water supply authorities in Australia genera lly have used such qualitative criteria to determine the adequacy of the water supplied to consumers. These criteria may be summarised as 'the provision of a wholesome and sufficient supply at the cheapest price' . No quantitative criter ia has as yet been officially adopted for water supp ly systems as a whole although some authorities have aimed towards WHO standards overall and some have adopted quantitative standards for the characteristics of water produced from water treatment plants and for

Dr D. W. Lynch is Supervising Engineer, Plant Design Department in the Melbourne and Metropolitan Board of Works. This is an extract from his paper presented to the A WWA Summer School, Adelaide, February 1980. 24

particular constituents of the water. Water supply systems may contain a number of components, from the source of raw water through to the consumer's kitchen sink and, for eac h of these components, there may be a number of options available to the water supply authority as to its design and operation. Such options in relation to the quality of water supply are discussed by Lynch (1980). This article discusses the management options available for one of these elements, namely, the storage reservoir.

PURPOSES OF STORAGE Storages a re primarily designed to ensure reliability of supply and an abso lute assurance that the water i~ microbiologically safe after trea tment. The benefits of storage include a reduction in numbers of bacteria and viruses and of BOD, suspended solid s, colour , turb idity etc. Often, such benefits need to be weighed against the disadvantages associated with algal blooms which may result from the intake of water high in nutrients . In addition, in Australia at least, storage provides the added benefits of: • more fl exibility in the choice of periods during which water is abstracted from the river; and, • more uniform flows to be passed to the water treatment facility. WATER

INFLUENCE OF RESERVOIR FEATURES The quality of water in reservoirs may be affected in the follow ing ways: • un sta bl e soil profiles a nd dispersive sub -soils m ay lead to increased turbidity particularly where the inflow is of low ionic strength ; • iron in soil s of high iron content m ay be subject to mobilization into so lution under anaerob ic conditions ; • high colour may be associated with the natura l vegetation and soi ls of high iron content; • nutrients m ay be released from inund ated vegetation; and, • oxygen depletion in the lower layers m ay result from th ermal stratification. The climate a nd the ageing characteristics of the reservoir will also affect the chemical , physical and biological characteristics of t he stored water .

the turb idity of the stored water with tim e is very slow. It would see m even more unwarranted and uneconomical to dose with gypsum (or other chemica ls) to red uce the 'turbidity where the outflow from the storage is passes to a treatment plant before entering the distribution system. A "wait and see" approach would seem to be best in suc h circumstances. High turbidities of the stored water are often encou ntered only during the filling stage and the in itial stage of operation of a reservoir . The design of the coagulation - clarification stage and sludge handlin g fac ilities of treatment plants is normally such that there is sufficien t capac ity to hand le increased solid s loadings on a short -term basis by appropriate operation. Acceptance of hi gh t urbidity leve ls in the reservoir may also have the advantage of reducing algal growths by limiting light penetration . T his could be a n important considerat ion where t he nutrient levels in the stored water are high.

MANAGEMENT OPTIONS T he fo ll owin g management options are available for controlling the qu a lity of the stored water: (a) cropping a nd removal of vegetation on t he reservoir floor - this decreases colou r , iron and nutrient levels but increases t urbidity; (b) control of erosion and stabi lization of soils and slopes by various means to red uce turbidity levels which may however increase nutrient levels . The means include : • physical (berms , grass, rock cover) • chemica l Oime, gypsum , al um applied either to the soil directly or to the inflowing water or to both), and biological (c) provision of a multiple level offtake stru cture in the storage to enable the selection and withdrawal of water of opti mum qu ality; (d) location of the outlet point remote from the inlet point to achieve max imum detention time; (e) artifici a l destratification or hypolimnetic aeration of the reservoir to increase dissolved oxygen levels in t he stored water (although nutrient leve ls may be increased); to prevent shor t-circ uiting of water through t he reservoir caused by temperature induced density currents; to decrease manganese and iron levels; to decrease corros ivity a nd to decrease colour , tastes and odo urs; (f) exclusion of the public from the reservoir catchment a nd / or discouragement of vandalism by appropri ate design and caretaking measures . If such m anagement techniques are un abl e to provide water of a satisfactory quality , physico-chemical treatment of the outflow will be necessary. Somm ervill e a nd Lawrence (1977) have indicated that, in the absence of treatment, th e most cost effective solution s for controlling t he outfl ow water quality from storage reservoirs feeding directly into a water distribution system are: (i) rock stabili zation of the steep and exposed areas a bove the minimu m operating level (MOL); (ii) mowing a nd rem oval of grass prior to filling ; (iii) grass stab ilizat ion of borrow pits below the MOL; (iv) dosing of the infl owin g water with gyps um ; (v) top-dressing the remaining areas a bove the MOL with gyps um prior to inund ation ; (vi) artificial destratification.

CHEMICAL TREATMENT Where chemicals are applied directly to stored water for turbidity red uction , very large doses may be necessary. For example, at Cardinia Reservoir, Melbourne 170 mg / L of gypsu m was a pplied initially to the inflowing wa ter foll owed by stepwise red uction in the dose during the filling period to 25 mg/ L this be ing gradually red uced thereafter. The objective was red uction of the turbidity to < 10 FTU (Sommerville and Lawrence, 1977). Soil stabilization a lso m ay need the application of large qu a ntities of chem ica ls. At Cardinia Reservoir , 20 tonne / ha of gypsum was applied to ac hieve a penetration of 1 metre (Sommervill e a nd Lawrence, 1977). Sufficient time (say 12 months) is req ui red between the application and inundation to preve nt leac hing. The use of chemicals to reduce turbidity at such rates and in such quantities is probably uneconomical except where the water is urgently needed in supply (as was t he case for Cardinia) or when the reduction in WATER

ARTIFICIAL DESTRATIFICATION AND HYPOLIMNION AERATION Both these techniques have been used with success in Australia and overseas (Burns 1977 , E.&W.S. Dept. 1977, Fast et al. 1976, and Lack et al. 1975). T he object ives of artificia l destratification include: • the elimin at ion of anoxic conditions in the hypolimnion by aerat ion; • the ma intenance of isotherma l cond itions of the stored water to ach ieve temperature control of the reservoir discharges; and , • the control of a lga l growths. Artificial destratification has rarely been used solely for the purpose of controlling algae, however its greatest potential benefit wou ld seem to lie in this area. T he current methods of achieving artifici a l destratification involve some form of either a mechanical p umping system or a compressed a ir injection system (E. & W.S . Dept . 1977). Australi an experiences have been limi ted to diffuse aerat ion systems. It is worth noting that t he wind strength significantly affects the energy input requirements . Burns (1977) has quoted some capital a nd operating costs for destrat ification of the med ium sized (37,600 ML) Tarago Reservoir, Victoria . A preliminary estimate of $270,000 and u p to $13 ,000 per month has been made for the capital a nd operating cost respective ly of destratifying the Sugarloaf Reservoir (capacity 95,000 ML, effective depth 48 m) Melbourne, should such become necessary. Such costs (November 1979) are less than 2% of the capital cost of th e Sugarloaf Water Treatment Plant and less than 5% of its operating cost. Artificia l destrat ificat ion offers conside,-able potential as a cost effec tive mea ns of at least minimizing and possibly overcoming the major problems associated with poor quality water in storages. Burns (1977) has indicated for destratification of Tarago Reservoir was only 6 % of the capita l cost of a multiple level offtake structure. It m ay then be that destrat ify in g aeration in stallations are more cost effective than multiple leve l offtake stru ctures in obtaining a better quality outflow . However multiple level offtake structures still have the great virtue of providing fl ex ibility in the manner in which water can be drawn off from the reservoir. Other points worth noting are: • aerat ion is only needed at a single or a very small number of locat ions to ensure destratification of the whole of the reservoir; a nd, • once a reservoi r has been destratified it ca n be maintained in that co nd ition by interm ittent aeration . Hypolimnion aeration is of limited use compared with artificial destratification because it does not enable control of a lgal growth in the epi limnion . It is however of use where aeration of the entire reservoir is unnecessary a nd ca n have the following advantages: • the nat ura l temperature distribution within th e reservoir can be retain ed; • less water a nd therefore less energy is involved in the mi xing; and , • nu trients solu bilized from sediment in the hypolimnion are not transported back to the epilimn ion to promote greater algal growths . Hypolimni on aeration ca n be achieved by either (Fast et al. 1976): • full air lift of the hypolimnion water to the reservoir surface, disentrainment of the a ir an d gravity return of the aerated water 25

direct to the hypolimnion; • downflow air injection into the hypolimnion to achieve aeration and mixing with the hypolim nion only.

GROWTHS OF ALGAE IN RESERVOIRS The problems assoc iated with excessive growths of a lgae and t he methods of their control deserve separate consideration because of the special difficulties involved, the potent ia lly adverse conseq uences on a wide range of water quality parameters and the costs incurred. Palmer (1977) has provid ed a n excell ent summ a ry of the relationship between a lgae and wate r pollution. The dry weight concentration of a lgal cells constituting a "bloom " may vary from as low as 30 ug/ L to as high as 4 mg / L (Bayley, 1971). A number of workers have developed mathematica l models for pred ict in g whether there will be sig nificant a lgal blooms in a particular body of water. Vollenweider' s (1968) set of simplified criteri a are well known , t hese being: (i) an inorganic nitrogen a real load in~> 5.0 to 10.0 gm / 2 year. (or an inorganic N concentration > 0.3 mg/ I) (ii) an inorganic phosp horus areal loading > 0.2 to 0.5 gm / m 2 year. (or an inorganic P concentration> 0 .015 mg/I) (iii) an alkalinity> SO to JOO m g/ 1 (as CaCO 3 ) (iv) the water be moderately hard. It is interesting to note that Brezonik (1971) has proposed different and somewha t less stringent criter ia . Various other tests , such as the saprob ity index (Pa lm er , 1977), have been developed as ind icators of wa ter quality or potential ferti lity. Such criteria are really only guidelines as other factors such as t urbidity, light intensity and penetration are also imp ortant . There are t hu s considerab le un certa inti es involved in trying to pred ict the likelihood and extent of algal growths in a reservo ir. Notwithstanding, it is essentia l from a design and forward planning viewpoint that an attempt be made to ass ign a probability to t he lik elihood of such events a nd to t he li ke lih ood and extent of t he res ul tant problems. Excessive growths of algae are most likely to occur during the summ er months when the water suppl y d em and from the pl ant is greatest. Such a lga l growths ca n affect the reservoir outfl ow water qual ity a nd may resul t in operational difficulties in the treatment plant, as fo ll ows: • death and lysis of algal biomass will provide a source of B.O.D. which will result in oxygen depletion and an in crease in the levels of iron, manganese a nd sulphide in the hypol imnion; 2 • hard ness of the water ca n be red uced by up to one-third (as CO 1s utilized by t he algae); • the pH and alk a lini ty of the water can be increased; • the sheer quantities of alga l biom ass coul d be difficult to remove by coagul ation - clarification as a lgae are naturally b uoyant and certain types of algae are difficult to coagul ate; • algae in the clarified water ca n significa ntly shorten filter run times, and increase the frequency of backwashing; • the qu a n tity of slu dge to be ha ndled and disposed of will be increased by incorporation of algae into the slud ge; • taste and odour compounds are generated by certain types of algae , these are difficult a nd costly to remove. ' • death a nd lysis of algal biomass may increase the level of colour and dissolved organics in the water, which can result in the production of chlorinated organics in the disinfection stage of the treatment plant. The fo ll owi ng meth ods have been tried to control or remove a lga l growths in reservoirs: (a) Destratification - The possibility exists for m inim izing sta nding crops of a lgae by tak ing them on a light-limiting path through the reservoir. T his can be achieved by mi xin g at a depth such that the respiration rate exceeds t he photosynthesis rate for a large proportion of the tim e. The species distribution ca n a lso be altered by mixing, as those species which have unique distributions with depth throughout the reservoir wi ll be adversely affected. (b) Treatment with an algicid e copper sulph ate, potassium permanganate, ch lorine and phenoli c compounds have all been effect ively used for this purpose; (c) Acceptance of or art ificia l ra ising of the turbidity level; (d) Removal by mechanical harvesting;

(e) Biological control such as grazi ng by zoo-plankton and fish. As indicated previously destratification has great potentia l for providing a low cost solu tion to t he problem of limit in g a lgal growth . Work undertaken to date, however, has indicated that destratification decreases a lga l crops in some cases and increases them in others. Furt her work is needed on the amount , duration a nd timing of t he m ixing required to limit algal growth . T he use of a lgicides seems only to be justified on a sma ll sca le on an intermittent basis and where t he immediate control of an algal bloom is important. The use of a lgicides on a long-term basis is not a costeffective method of controlling algae a nd may introdu ce other undesirab le pollutants into the raw water. For example, the chem ica l cost a lone of a single dosing of the Sugarloaf Reservoir, Melbourne, with 0 .2 mg/ L of copper su lph ate would be some $20,000 (November I 979). The epi limnion depth assumed was 20 metres and the reservoir surface area 445 ha. The prob lems and costs of distributing copper . sulp hate throughout a reservoir of large surface area to ens ure that such dosing will be effective are also significa nt . This method d oes not compare favourab ly with destratification. Copper sul phate use a lso has t he d isadvantage that sol uble and part iculate copper could be present in t he reservoir outflow. Under the appropriate pH cond itions th is copper could be re-dissolved in the treat ment plant a nd later precipitated in the distribution system. Re mova l by mechanical ha rvestin g a lso offers some promise as a low cost solu t ion to alga l p rob lems. Koopm a n and Oswald (1977) have est imated the cost of a ski mmin g and microstra ining installation to be about 50 % greater th an that for treatment with copper sulphate. Further development may reduce this cost as we ll as provide a more comprehensive solu t ion to disposal of t he concentrated algae stream produced. · It is a lso t heoreti ca ll y possible to limit algal growth by removing phospho ru s l'rom the infl ow to a reservoir by precipitation with lim e or a lum but this is not econom ica l. For example, the chemical dosage of lim e req ui red , to reduce t he solu ble phosphorus level below 0.01 mg / L would be in excess of 2000 mg / L. Furthermore the phosphate deposited in the reservoir sediment cou ld be released in soluble form. In sma ll er reservoirs, where there is significant accum ul ation of such und esira bl e materials in the bottom mud , provision could be made to draw water off from t he lower layers a nd pass it to a small er downstream impoundment (or sedimentation tank) for treatment. A multiple level offtake str uct ure ca n be used to selectively withdraw water from a level where algae are not present and / ol where the water quality has been least affected by the products of a lga l decomposition.

CONCLUDING REMARKS

Water supply authorities are faced with in creasing pressures to draw from surface water sources to supp lement their water supplies, to impound water of poorer quality and to meet more stringent standards in the quality of water delivered to the consumer . A large num be r of management options are ava il ab le for the design and operation of each of the various elements in t he water supp ly system to meet more stringent water quality standards. Some of the difficu lties assoc iated with meeting particular water quality standards can be overcome by fair ly simple engineerin g methods , by proper forwa rd planning a nd by providing sufficient flexibility in the design of t he facilities for their future needs and operation. T he amo un t of published in formation on t he cost of treatment of raw waters of d iffer in g quality by various processes is very limited particularly in regard to the variat ion of such costs as a function of the water quality parameters adopted as stand ards a nd the levels at which t hey are set. Each a uth ority will need to determine for itself the most cost effective solu1i on for each speci tic case taking in to accoun t the paiiicular design and the adm inistrative, financ ia l a nd other requirements. Study of t he water q ua lity, design aspects and other investigations should be undertaken at the preliminary stage. More particularly a proper economic eva lu ation of all the management options ava il ab le shou ld be undertaken by the water supply a uth ority to ensure that water of the desired qu a lity is provided at the optimum cost.

REFERENCES -

Continued on page 28. WATER

CONFERENCES AND COMMENTS CALENDAR 1980 October 7-9, Lo ndon Int ernat ional Conference Coas tal Discharges - E ngineering aspects. October 11-16, Victoria NWW A annaul meeting, conference on dri lling, sa mpling comm unications . October 13-16, Minneapolis 16th American Water Reso urces Conference (A.W.R.A .). October 13-17 , Melbourne Second H ydrographic Work shop (Au st. Hyd . Soc .). October 13-18, Veld erhoven Net herlands Semin ar on Eco nomic Instrum ents for Nat Âˇion al Utilization of Water Resources.

1981 January 1981 , 9th New Delhi IAHR Conference. January 25-31, Christchurch, N .z. International symposium on erosion and sedim ent transport. Jan uary 27-29, Ba ngkok S. E. Asian regional symposium on problems of soi l erosion and sedimenta ti on. Feb ru ary-March, Perth P e rth Metropo lit an (CS IR O / WRFA).

Groundwa t er,

March, Noordwijkerho ut , Net herlands Internatio nal sy mposium on th e quality of groundwater. (N eth . Inst. for W.S .) . Marc h 23-27 , Canberra I. E. Au st. 198 1 E ngineering Conference .

October 15-16, Melbourne National Conference on costs and benefits of environmental protection (C'wealth Dept. Science and the Env ironment and EPA, Vic.).

Marc h 30-April 1, Berlin Wass er Berli n '8 I .

October 19-31, Rolla, Missouri Two week course o n Environmental Analysis for Tox ic Meta ls .

April 2-3, Berlin lWSA speciali sed conference on instru mentation monitoring and automation in water protection and supply .

Nove mb er 3-8, Brighton , U.K. Conference on th e environment impact of man 's use of water (IAWPR) . Nove mber 4-6, Adelaide Hydrology and water resources symposium (I.E. Au st.)

Marc h 31-1 April , Berlin IWSA specialised conference on low cost te hn ology in water supply.

Ap ril 6-10, Perth, A ustralia A WW A 9th Federal Convention. May 3-7, Bratislavia Int ern a tional con Ference on numerical mod ell ing of ri ve r, channel and overland fl ow. (!AHR , WMO , l! ASH)

Nove mb er 12-13, Perth, W.A. Land and stream salinit y seminar a nd work shop. (P.W . D.)

May 11 -15, Brisbane 51st AN ZAAS C onference .

Novemb er 14-18, T ownsvill e Groundwater Re -c h arge (AWRC) .

June 14-19, Urbana, U.S.A. 2nd International Conferen ce Storm Drainage (IA WPR).

Confe r e nc e

on Urban

Nove mb er 14-24, Edmonton , Ca nada Third International Symposium on Water Rock Reaction (Alb. Res. Counc il).

June ?? , Toronto , Canada 2nd Symposium on Interaction of Sedime nt and Fr es h Water (UNESCO) .

Nove mb er 15-17 , Brisbane Eng in eer ing education conference (I. E . Au st.). Novemb er 17-21, Adelaide Si lver Jubilee Con fe rence, A'a sian Corres . Assoc . Nove mb er 21-23, Idaho, U.S . A. Watershed management symposium (ASCE). Nove mb er 24-28, Canberra . First internationa l conference o n technology for development (I. E. Aust.) .

June 15-19, Brighton, U. K. Water Industry 1981.

Nove mber 25, Sy dney Sy mposium, AWWA / WRFA. Water Supp ly Demands in Town s and Cities . December 1-5, Can berra 4th In ternationa l Symposium on Nitrogen Fixat ion. December 3-4, London Symposium on energy use and conservation in the wa ter indu stry (Inst. Water Eng. & Sc ient ists). December 20-22, Roorkee, India Symposium on wa ter resource systems.

WATER

June 20-26, Munich and Rome Water quali ty monitoring (IA WPR). August 1981, Grenoble, France 11th Int. Irrigation and Drainage Cong ress (!CID). A ugust 10-14, San Francisco Water Forum 198 1 (ASIE) . Septemb er, Melbourne Hydrology Sympo sium. September, Jonkoping, Sweden International Tra de Fair and C onference on water conservancy and polluti on control. Se pte mber, West Ge rmany 8t h Int ernational Congress on Metallic Corrosion . Se pte mber 6-12, Travemund e, Germany 2nd International Symposium on Anaerob ic Digesti on. May , 1982, Syd ney 52nd ANZAAS Conference.

AMERICAN WATERWORKS ASSOCIATION RESEARCH FOUNDATION

WATER REUSE SYMPOSIUM CALL FOR PAPERS The symposium , to be held in Washington D.C ., August 23-28, 1981 will be devoted to meetings devoted to the renovation and reuse of wastewat ers from muni c ipal , indu strial and agricultural sources. In selecting papers specia l considerat ion wi ll be given innovative approaches, new and/or unreported syste m information, practical applications of water reuse and recyc ling of water. Tho se interest ed shou ld submit 10 copies of abstracts not exceeding two papers by Dec. 15, 1980. Further information from Richard D. Heaton, Water Reus e Symposium 11 , AWWA Research Foundation, 6666 W. Quincy Ave., Denver, Co lorado, 80235.

MANPOWER AND EDUCATION THE WATER INDU STRY REPORT BY B. E. Lloyd and C. J. Nevill On behalf of the Australian Water Resources Counc il , the M.W.S.&D. Board, Melbourne has completed a Review of Water Resources Education in Aust ral ia. The proj ect was funded by the Dept. o f National Development and Energy . The object of the study was identification o f present and future manpower needs and assessment of the adeq uacy of ed ucat ion for these needs. Summarising the pri nc i pal finding s: There is a need fof a body at national level to cont inually review manpower and edu cation. The major issues before the industry over the com ing decade relate to meth ods o f finance and organisational c hanges as Autho ri ties move from 'cap ital' 'to recurrent ' phases. Sustained demand for water and wastewater plant operators is likely. Closer co-operat ion of existing educat ion provisions w ith TAFE would be advan tageo us. Future tradesman needs w ill be met by continuin g support of app renticesh i p. Techn ician occupat ions will in creasingl y be filled by middle level personnel. These occ upat ions shou ld be reviewed and suitable ed uca tional course s establi shed for them. Middle level ed ucation wou ld benef it from bette r co-o rd ina t ion between TAFE authorities and more widespread use of subÂˇ jects already developed in N .S.W. and Queensland . Civ i l Engineering wi ll remain the dominant profess ional discipline. The industry employs 20 % of practising c ivil engi nee rs and the re c ru itment o f new graduates sho uld rema in at the low levels c urrent for the last 213 years. Expansion of water related subjects for undergraduates seems unnecessary. The 1980's will require broadening and supplement ing of post-graduate educati on in speciali sed tec hni cal studies, environmental scie nce and management. A new graduate diploma course is o ut lined. Cont inuing ed ucation needs supp ort by the water industry . The Department of National Development and Energy advises that th e Report shou ld be available in October.

ENVIRONMENT/ENERGY INTERACTION REPORTS AVAILABLE With the possibility looming of largescale projects for the extraction of liquefied fuel from oil shale , the question of impact on the environment land , air, water, biological and human , looms equally as large. As part of a series of staff papers of the Department of Science and the Environment (A.C.T.) on Environment/Energy interactions , an an notated bibliography on these issues has been prepared by Mr. Ian Gorrie of the Department . Interested Members may apply to the Department for copies of these reports.

ENERGY USE AND CONSERVATION IN THE WATER INDUSTRY SYMPOSIUM - 3-4th DEC 1980 - LONDON The Institution of Water Engineers and Scientists

Papers for discussion will include: • The National and International energy situation . • Water resources ; pumping and distribution. • Water treatment plant; design and operation for low energy use. • Sewerage and sewage disposal new processes versus old. • Sewage - development of byproducts. • Energy management: the Thames ex perience. • An international view. Further information from Deputy Secretary of the Institution, 6-8 Sackville St ., Piccadilly, London, WIX IDD .

A.W .W.A. 4TH SUMMER SCHOOL LECTURE NOTES Available in Sets

of Two Volumes

$30 per SET from Dr. J. CUDGLY SUMMER SCHOOL SECRETARY STATE WATER LABORATORIES E. & W.S. DEPT. PRIVATE BAG SALISBURY 5018

Chequ es payable to : AWWA Summer School

ENVIRONMENTAL PROTECTION COSTS AND BENEFITS CONFERENCE Melbourne - 15, 16 Oct. 1980 Case studies will be presented by Industry, Governm ent and international sp eakers co mplem enting th e theoretically based 1978 National conference on Environmental Economics. Keynote speaker will be Mr. J . W. MacNeill , Director of OECD Environmental Directorate. Topics will include: • Costs and benefits - Corporat e and Industry views. • Measuring the Benefits . • Estimating Costs of Pollution Controls to Industry. • Ec onomics of Ha zard o us Chemicals controls. • Cost Effectiveness of Coal Waste Recovery and Mine Rehabilitation. • Energy Alternatives and the Environment. • Costs and Benefits of Pollution Control in the Pulp and Paper Industry. • Mine Rehabilitation - Cost Effectiveness, N .S .W . • Public Sector Costs of Industry Effluent Treatment. • Vehicle Emission and En vironmental Protection . Further information : Conference Secretariat, Environment Protecti on Authority, P.O. Box 41 , E. Melb. 3002 (03-651 -4011 ).

SANDFORD D. CLARK Continued from page 18 The subsequent fin ancial collapse of th at settlement led to a Royal Commission and th e Chaffeys beat a hasty retreat to Renmar k. They were not alone in their misfortune, how ever. Although numerous local Irrigation Tru sts were initially formed in Victoria, th ey were short-lived and their fin ancial di ffic ulti es ultimately led to the creation of th e State Ri vers and Water Supply Commission , which largely too k over their fun ction. Experience in other States which experimented with local Irrigation Trusts has been generally similar, although it seems th at the equivalent Trusts to establish waterworks in country areas did not always fare so badly. Nevertheless, th e pattern of a central State authority with ultim ate responsibility for irrigation and water supply throu ghout mu ch of th e State has become universal in all States .

REFERENCES U nited States Department of Agriculture, Office of Experiment Stations, Bulletin No. 100: Report of Irrigation Investigati ons in Cali fo r nia, p , 53.

2 Victoria, Royal Commission on Water Suppl y, First P rogress Re port, 1884, pp . !09- 1IO; Victoria, Parliamentary Pa~rs 1885, Vol. 2, p. 54. 3 T his was achieved through legislation such as the Drainage of Land Act I 958 (Vic.), which provides for drainage across adj acent land, and the Water Act 1926-1979 (Qld .) s. 62, which provides for sharing of excess bore water. 4 Victoria, Parliamentary Debates, Legislati ve Assem bly, 13 July 1886, p. 679 . Water Act, 19 12 (N.S. W. ), s. 4A ; Water Act 1926- 1979 (Qld .) , s. 4; Water Act 1958 (Vic. ), s. 4; Rights in Water and Irrigation Act 1914-1978 (W .A.) , s. 4. 6 Control of Waters Act, 191 9- 1975 (S .A. }, s. 4. 7 Water Act 1926- 1979 (Qld .), s. 5; Control of Waters Act, 1919- 1975 (S .A .) , s. 5; Water Act 1958 (Vic. ), s. 5; Rights in Water and Irrigation Act, 1914-1978 (W .A. ), s. 5. 8 Water Act 1926- 1979 (Qld .). s. 8; Cont rol of Waters Act 19 19- 1975 (S .A.) , s. 9; Water Resou rces Act 1976- 1979 (S.A. }, s. 27; Water Act 1958 (Vic.) , s. 8; Rights in Water and Irrigation Act, 1914- 1978 (W .A.) , s. 8. 9 The Water Acts typically allow a person owning land adj acent to a stream to take water fo r domestic and stoc k purposes , without a licence. T his is a new right , given by statute, however , and the question re mains wheth er other aspects of the common law riparian right continues to exist.

D . W. LYNCH Continued from page 26 REFERENCES BAYLE Y, A. W . " Nut rien t Removal fro m Wastewaters", J. Inst. oif Public H ealth Eng. , 70 , p. 150, (1971). BREZON IK, P. L., and SHANNON, E. E. , 'Trophic State of La kes in North Central Florida •, Fla. Water Res. Centre Pub!. 13 (1 97 1). BU R NS, F. L., " Destratifyi ng Tarago" , Aqua, 23, p .15, (1977). ENG l NEERl NG & W ATER SU P PLY DEPA RTMENT, ADEU ADE, 'Artificial Destra tificati on of Reservoirs', Proc. of 18th Bienni al Conf. of Engineers Represent ing Authori ties Cont rollin g W.S. & Sew. Un'tlerta kings Serving Cities and Tow ns of Aust., p.90, Canberra, October 1977, (AGPS 1979). FAST, A . W. and LO RENZEN, M. W., 'Synop tic Survey of Hypolimnetic Aeration' , J. Env. Eng. Div. - ASCE, p. 11 6 1. (1976) . KOOPMAN, B. L. an d OSW ALD , W. J ., ' Nuisance Algae Control Thro ugh Mechanical Harvesting' . Water & Sewage Works, p.64, 124, (1 977). LAC K, T. J . and CO LLI NGWOOD , R. W., 'The Cont rol of Reservo ir Water Quality by Engineering Meth od s' , W. R. C. Symposium on T he Effects of Storage on Water Q ualit y, Read ing, 1975, p.485. LYNC H , D. W., 'Some importa nt manage ment issues concerned with the quality and cost of potable water sup plies' . A. W. W .A. Fo urth Sum mer Schoo l, Adelaide, Australia, February 1980. PALMER , C. M., Algae and Water P ollution : An Illu st r a t ed Man u a l on th e i den tifi ca ti o n , Signi ficance and Control of Algae in Water Supplies and in Polluted Water, LEW IS, R. L. ed. , EPA-600/ 9-77-036, (December 1977). SOMMERV ILLE, P. J. and LAW RENCE, l. A. , ' Management of Wate r Quality in New Storages A Case Study', 7th A.W.A.A. Federal Con f., Canberra , September , 1977. VOLLEN WEIDER, R. A., 'Scientific fundamentals of the eutrophication of la kes and flow ing waters with particular reference to nit rogen and p ho s p horu s as fac tors in eutr op hi cat io n ,' O. E.C.D., Paris (1968).

WATE R

9TH AWWA FEDERAL CONVENTION PERTH, W.A. 6TH .. 10TH APRIL, 1981 A magnificent response to the call for papers has resulted in acceptance of 86 papers covering 11 subject groups. HIGHLIGHTS • Three program streams in parallel for much of the Convention will offer a wide range of options. • The Opening and Keynote Address will be at the luxury Sheraton-Perth Hotel. • An Omoebic Meningitis Forum will include four papers by leading microbilogists. • Effluent Re-use and Wastewater Disposal will provide eleven papers covering the latest experience. • Industrial Wastes will be covered by thirteen wide-ranging papers. FIELD VISITS will include the new Swan Brewery, Canning Vale groundwater recharge experiments and Jandakot groundwater treatment plant. TOURS AND LADIES ACTIVITIES will be of great interest and include a low cost visit to Singapore. Registration Forms will be available early December. Enquiries to Convention Secretariat, Cl- Institution of Engineers (Aust.), 712 West Perth, 6005. Phone (09) 321-3340. Display Space Enquiries: Bob Fimmel (09) 321-0321 -

immediately.

PORT ABLE WATER SAMPLERS AND FLOW METERS Struers portable instruments are designed for composite sampling, fractional sampling, and flow proportional sampling of water in streams, weirs, sewer systems and waste water treatment plants.

AQUAPROPOR PRT41 is a portable , battery operated instrument for measuring water flow in open c hann els and can also be used for flow proportional control ot a water sampler co nn ected to the instrument. It provides a digital read -o ut ot water flow and vo lum e whi ch can be recorded on a flow recorder co nnected to th e instrument.

AQUASAMPLER HCV14 is a co mpact unit to r regularly sampling running water. It consists ot a 12V battery-drive n per istal ti c pump with co ntinuously variabl e freq uency setting w hi c h provides a pump ing volume ot between 0.3 and 3L/h.

AQUAFRACTOR HCV70 is a fra cti o nating unit w hich can be used with the AQUASAMPLER HCV .

SELBYS SCIENTIFIC LTD. Melbourne 544 4844

WATER

Sydney 888 7155

Brisban e 371 1566

Perth 451 2577

Adelaid e 51 4651

Hobart 28 4691

SYMPOSIUM (Preliminary Notice) WRF and AWWA - . N.S.W . Sydney - Nov. 5th, 1980

WATER SUPPLY DEMANDS IN TOWNS AND CITIES - ESTIMATION AND MANAGEMENT The tentative programme includes: • Urban Water Demands - Causes and Effects. • Water use and availability in N.S.W. Country Towns. • Variability and Persistence of High Daily Demands in Urban W.S. Systems. • Predicting Water Supply Demands . • Demand Criteria for Design Purposes . • Living with your Friendly Neighbourhood Drought. • Supply from Bores - Potential for Underground Storage. • Getting the Central Coast Region through the 1979 Drought. • Dual Water Supplies. Further information from Secretary, Joint Symposium , Clo R. R. Ash , 37 Boronia Ave. , Cheltenham, N.S.W., 2119 .

PETTIGREW CONSULTANTS PTY. LTD. Pollution Control & Water Treatment Engineers P.O. Box 94, Rock/ea4106 Telephone 200-1176

RIVER SANDS PTY. LTD. High Quality

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

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BOBY /

44 Koornang Road, Scoresby 3179

Telephone 763 8988

BOBY ANAL YT/CAL LABORATORY SERVICES

• Industrial waste water , sewage and process water analysis. • Waste disposal investigations to M .M.B .W. and E.P.A . requirements.

One Recorder for all flow sensors! Yes. our new P100L Flow Recorder works with Pitot, Venturi , Dall, Or~ice, Turbine, Vortex or Electromagnetic flow sensors. Not only that, you ca n have one or two pens, three type s of built-in square root extractor or pulse /analogue converter. There's an internal power supply to feed 2wire d.p. transmitters, a choice of roll or fanfold 100mm c harts, a sealed inking system and direct linear motor pen drive. Send for the facts today

BBC

CONVEYORS

11111

22 Wayne Coun. O.ndenong, 3175. " ' - " 791-2912

BROW N 80VEAI

Kent Instruments (Australia) Pty Ltd Sydney Melbourne Adelaide Brisba ne Perth

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525 2811 87 4 1233 352 1455 36 1311 277 5377 PJ 2104

WATER

Whatever the pipe, there's a

to clean it, test it and de-water it at lower than 11 normal costs! MANUFACTURED FROM FLEXIBLE POLYURETHANE FOAM AND AVAILABLE WITH A VARIETY OF COMPATIBLE POLYURETHANE COATINGS AND ABRASIVES. Girard Polly-Pigs are the most effective and versatile pigs on the market. The patented design principle is that of a simple resilient cylindAr which has a vapour seal in th e base. When pressure is applied to the base, the polyurethane is forced to expand against the pipe wall. This provides a tight seal and exerts a scraping action as the Pig travels through the line. Fluid, (air or gas), saturate the open wall foam cylinder allowing the Polly-Pig to become part of the actual flow. As one satisfied user -said: " I think these pigs are crossed with a ferret the way they can manoeuver."

Polly-Pig's unique design enables it to: • cross tees • pass through valves • make short radius turns • clean multi-dimensional lin es Exclusive Distributors

LORD CO

SCARLET DURA-COAT fo r lo ng est run s and to ughest i,;lea ni ng jobs.

WATER

(AUSTRALIA} PTY. LTD.

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• . This 11isteric ollfttain ash seedling ,as pt Jeeralang Tree of A.P .M: fortSts Pty. Ltd Ranges. South Latrobe Valley in Victori Pione s cleared most of the agriculture d eJatter pa~ of the nin Over two generations many of the sett land and the farms gradually reverted to scr noxious weeds. Today the Strzeleckls are the scene of one of the most exciting and successful reclamation schemes of Its kind in the world, brought about through the co-operation of the Forests Commission, Victoria arid A.P.M. Across the hills new forests are now growing. Our 150 millionth tree planting is amilestone which recognize~ tha Ing of this desolate area into anational asset. ·" · A.P.M. Forests has established atotal of ovtr 70 000 hectares el pino.4t and eucalypt plantations in Victoria. New Soutb Wales and Queensland, and , continues to _plant fer the future. ·

WATER

Still living in the past? Still relying on . the old methods?

YOU'RE IN THESO's NOW&ANEW ERAIN FILTRATION Filtration With ZETA PWS ELECTROKINETIC ADSORPTION Brings You Up-To-Date. Â· Asbestos-free Zeta Plus filtration media provides high efficiency, low.cost, micron and submicron depth filtration at high flow rates. Available in sterilisable high wet strength sheets, discs and cartridges to fit all makes of filter presses as well as Zeta Plus sanitary and industrial housings.

FOR BEVERAGES - PHARMACEUTICALS - CHEMICALS - COSMETICS - VEGETABLE OILS . ..

Cuno Division,

American Machine & Foundry Company (Aust) Pty Limited, B.M.A. Tower, 815 Pacific Highway, Chatswood, 2067. Telephone: 4115222. Telex: AA21426. A 1<Jboidiary of /Wif- Incorporated.

Cuno

Distributors In all major cities of Australia, New Zealand and South East Asia. PJ 1867

~51-IARPLES

You cannot compare the Sharples Sludge Oewatering Centrifuge with other conventional sludge dewatering systems because a centrifuge has so many 'pl us factors ' in its favour.

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Centrifuges are tot ally enclosed . No offensive smells .

RRI

Centrifuges occupy much less space th an other sludge dewatering system s.

Centrifuges don 't suffer from scree n blind ing they have no screens .

~~ Centrifuges.can ac cept wi de variati ons in 'feed ' concentration .

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Centrifuges ca n operate in th e open - no cos tly hou si ng - reduced 'civi ls'

Centrif uges hand le over 80% of sludge de watering duties in th e Unit ed States of Am erica ot wh ich more tha n 50 % are SHARP LES install ations

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Sharples have more experience - more municipal centrifuge installations in the UK th an any other centrifuge supplier. Sharples have the widest range di sludge dewatering centrifug es - to suit any sludge and any capacity .

~~ Sharples SOC Centrifuge standard construction is stain less steel eliminating corrosion problems .

Sharpl es have perfected a new and revolution ary hard surfacing technology to protect wea ring parts which in operation out lasts oth er hard surface treatm ents by as much as 30 time s.

~~ Sharpl es Ce ntrifuges are backed by a fully trained Serv ice Tea m and a comprehensive Spares faciiity.

Bri ti sh bu il t with Br itish labour. Faced with all these tacts and we have plenty more to support our clai m th at th e Sharpl es SOC Ce ntrifuge is the oniy compl etely cost eff ectiv e answer to sludq e dewatering or sl'-!dge concentration.

SHARPLES-STOKES ÂˇPTY. LTD. MAIL: BOX 367, ARTARMON. N.S. W. 2064 PHONE: SYDNEY 439-3378/4458 CABLES: PENNWALT SYDNEY