December 2009 - WIOAwioa.org.au/documents/waterworks/WaterWorksDec2009.pdf · 4 WATERWORKS DECEMBER...

December 2009

2 WATERWORKS DECEMBER 2009

The latest Health Stream (September 2009)includes reports on the Brisbane fluorideincident and pathogen related water qualityincidents at Jindabyne and the ski resort ofSmiggin Holes. In the Brisbane fluorideevent, fluoride continued to be dosed intotreated water despite the plant being offline.At Smiggin Holes up to 400 people becameill in a number of different ski lodges. AtJindabyne, sewage overflowed into lakeJindabyne due to a failure of a seweragepump. In both the latter events a boiledwater notice was put in place.

In analysing these events, a commontheme emerges - the reliability of alarmsystems and of the follow up systems thatare in place to respond to an alarmcondition.

I have spent time in many WTPs andcarried out a significant number of WTPoperational reviews across the country. Arecurring theme is the poor state of thealarm systems. Common problems identifiedinclude:

• Inactivated alarms. Often done byoperators simply because the alarms werebeing repeatedly triggered when no alarmstate existed. This was “driving themmad” and the utility had failed to correctthe problem.

• Alarm limits set deliberately high to avoidfalse alarms.

• Alarm limits that bear no relationship tothe Risk Management Plan critical limitsor HACCP limits.

• Poor, or no, calibration ofinstrumentation controlling alarms.

• Inadequate checks of alarms. Anelectronic instrument output check doesnot constitute an alarm check.

• No provision for automatic shutdown ofthe plant when critical parameters areexceeded. Also, confusion as to which, ifany, alarms shut a plant down.

• Failure of critical alarms that are supposedto shut a down a plant as defined in aRMP.

• Poor logic behind the alarms available.For example, turbidity meters on treated

water but none on the raw water orclarified water. This means there is noprovision for an early warning and whenthe treated water exceeds the limit, tosome extent it is all too late, particularly ifthose alarms are unreliable or fail.

• No escalation system in the event thatthere is no response to an activated alarm.

• Failure to identify alternative notificationsfor the situation where the nominatedofficer is on leave.

• Inappropriate prove times - both too longand too short. Short prove times are likelyto lead to false alarms that lead tooperators possibly ignoring alarms orinactivating them or raising the limits.

• Alarm limits changed by on call staff toavoid being called out during their on callperiod can either be because they don’twant to be called out or because they lackconfidence and training in the operationof the plant to feel confident they knowwhat to do if the alarm is activated.

• Alarms and alarm limits not clearlydisplayed on plant control systems.

• Alarm limits that have been changed andno one really remembers when and bywhom.

• Many alarm set points are notappropriately protected and there aresuspicions that alarm limits are changedby staff without the necessary knowledgeor appreciation of what the alarms are for.Once changed, they appear to staychanged.

• Assumptions by senior management thatall alarms are in place.

Alarms are an integral part of processmonitoring. They should be established tosupport the achievement of the targetobjectives and critical limits identified ateach control point and thereby help toprotect the consumer from exposure tounsafe drinking water. The limits andactions should be based on a riskmanagement assessment and a control pointapproach to water quality management asrecommended in the ADWG Framework forthe Management of Drinking WaterQuality.

A number of brief general suggestions areoffered here.

1. Critical alarm limits should be set to helpprotect public health. The definition of acritical alarm is simple - critical alarms arethose that should the parameter being

Editorial Committee

Peter Mosse, Editor

[email protected]

George Wall

[email protected]

Direct mail to:

Peter Mosse

WaterWorks Editor

c/-WIOA, 22 Wyndham Street

Shepparton Vic 3630

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WaterWorks is the publication of the Water Industry

Operators Association of Australia (WIOA). It is

published twice yearly and distributed with Water

Journal. Neither the WIOA nor the AWA assume

responsibility for opinions or statements of facts

expressed by contributors or advertisers. All material

in WaterWorks is copyright and should not be

published wholly or in part without the written

permission of the Editor.

Contributions WantedWaterWorks welcomes the submission of articles

relating to any operations area associated with the

water industry. Articles can include brief accounts

of one-off experiences or longer articles describing

detailed studies or events. These can be emailed to

a member of the editorial committee or mailed to

the above address in handwritten, typed or printed

form.

CONTENTS

Editorial 2

Letter to the Editor 5

The Five Day Challenge 6

Operator Exchanges in Germany 9

TopOpShot 12

Vermin Proofing Potable Water Storages 14

Covering Clarifier Launders Controls Algae 16

Revving up a Recycled Water Plant 17

SEQ In Transition - Then and Now 20

ASR Trials at Barwon 22

E D I T O R I A L

ALARMING PROBLEMSPeter Mosse

OUR COVER

Our cover shot shows a deep bedexcavation being carried out in a filter toexpose a few nozzles for inspection.

Automation IT - # 1 in Alarm ManagementPhone: 07 3299 3844 Email: [email protected] Web: www.automationit.com

Automation IT are licensed system integrators for Matrikon and use the extensive Alarm Manager software tools to provide a complete rationalisation of plant alarm systems. Common problems are identified and a detailed report is provided along with the necessary updates to the plant’s control system to rectify the issues. The software tools allow not only alarm system analysis, but also feedback on how your operators are interacting with the alarm system and how many alarms are being ignored as well as how long it takes to react to alarms. This data can then be benchmarked to ensure that the operator loading observed falls in line with “Best Practice” operator loading objectives as outlined in EEMUA #191 guidelines. It is not uncommon for unaudited modern plants to exceed the recommended guidelines for alarm loading by an order of magnitude!

Automation IT has extensive experience in the design and implementation of alarm management systems as well as fullsystem integration and MES capabilities. For more information please contact our office on the number below.

How much time is spent manually checking alarm issues?

When did your plant last review critical alarm set points in the PLC?

Do your operators get frustrated with the number of alarms?

Are critical alarms sometimes missed due to the total number of alarms?

Can you rely on your alarm system 100%?

Has your site experienced downtime or compliance issues from:• Chattering or nuisance alarms?

• Alarm floods when power is lost or isolated?

• Operators complaining about or ignoring the alarm system?

• Unreliable alarm paging systems due to calibration issues?

• Too many alarms occurring?

Does any of this sound familiar?

You need Automation IT to perform an Alarm Rationalisation at your plant!


monitored exceed the limit, it will result in the production ofunsafe drinking water. Clearly, critical alarms necessitate plantshutdown. When critical alarms are activated the plant should shutdown automatically. What is required is a clear definition of whatparameters are to be alarmed and which ones should shut the plantdown. For a WTP, consideration should be given to the followingconditions automatically shutting the plant down:

a. Significantly elevated raw water turbidity

b. Alum dosing failure

c. Elevated clarified water turbidity

d. Elevated turbidity in water from individual filters

e. Elevated turbidity in combined filter flow

f. Failure of the disinfection system.

2. Alarm limits should be set as part of the process of implementingthe control point philosophy of the ADWG Framework.

3. The alarm limits should be linked to the target objectives andcritical limits determined for the control points.

4. Appropriate delay (prove) periods should be established to ensurethat alarms are not activated inappropriately.

5. Alarms should be tested. This includes a full test where thealarm is activated by altering the conditions at the sensor andallowing the “system” to run right up to checking paging systemsand implementation of incident management plans. In particular,the timely and appropriate shut down of the plant should beassessed.

The concept of an alarm in the water industry is often poorlyunderstood. The alarm is often simply regarded as being analogousto a wake up alarm. A time is reached and a noise is emitted andsomeone wakes up. However an alarm is actually an alarm system -a complex set of interconnected actions and responses.

An alarm is triggered in response to some deviation in ameasured parameter. The objective of the alarm is to bring about achange in an operational process that results in a change in themeasured parameter back into the target range. As such it involvesmany steps using different modalities:

1. Physical, chemical, electrochemical measurement

2. Electrical/electronic

3. Telecommunications

4. Human recognition and reaction

5. Process modification

6. Change in measured parameter

The need for alarm checks is obvious. The check should be a fullcheck, not just a 4-20 mA or other electronic check. The alarmcondition should be triggered by modifying the water quality nearthe sensor. For example:

1. Remove the on line pH probe and place it into a beaker of thesame water that it was in. Add a drop of acid or alkali to the waterto take the pH outside the alarm limit.

2. Add some turbid water to the turbidity analyser or alternativelyadd some formazan standard to the turbidity analyser.

In each case watch, wait and see what happens. Check the wholealarm response. This includes the initial triggering of the alarm,notification of the operator and activation of the escalation processif the operator link fails.

Each alarm should have a time period for the measuredparameter to exceed before the alarm is triggered. This periodshould be adjustable, however to prevent general access to thisadjustment, it should be password protected and only be availableto the main plant operator, supervisor and manager. This isnecessary to avoid “fiddling” with the delay period just to avoid“inconvenient” activation of alarms.

There is an urgent need for the industry to be aware of theselimitations relating to alarms. All too often there is an assumptionthat alarms are in place but there is no effective checkingmechanism. Operators often know the alarms are inactivated buthave chosen for one reason or another not to report them. Sadly, insome cases they have simply given up because of the lack ofresponse to their notifications or requests. In other cases, trainingof operators at a specific site fails to identify these critical controlsto the point that they just don’t know.

If the industry needs a reminder beyond the three incidentsreported in Health Stream then reading Steve Hrudey’s book (SafeDrinking Water. Lessons from Recent Outbreaks in Affluent Nations)is recommended as it contains case studies on amongst manyothers, the Milwaukee, Gideon, Galway, and Walkerton incidents.The threat from pathogens is real. Unfortunately the response tothe need for alarms is all too often one of complacency, a wordused at least once at the Walkerton inquiry and one that SteveHrudey uses throughout his book. The two events in the AustralianAlps are a reminder of what can and does happen. The event inBrisbane was too close for comfort.

There is a need to get the alarms right, get the number of alarmsright, get the priority level correct and use them to the advantage ofthe operators, the utility and the consumer.

E D I T O R I A L

Have You IdentifiedAll The Hazards??

Most operational management systems incorporate anassessment of hazards and associated risks. See if youcan work out an unusual hazard for a WTP from thephotograph above taken at a WTP recently (answer onpage 11). What preventive measures should be put inplace?

WATERWORKS DECEMBER 2009 5

I recently had the opportunity to consider the paper ‘WaterIndustry Operations, A Need for Reform’ prepared by GeorgeWall, Peter Mosse and Peter Bernich for the Water IndustrySkills Task Force.

In recent times I have read a number of papers and letters inWater Industry publications which would leave the readerthinking that there are few opportunities for training in ourindustry and those that are available are ineffective.

I would like to point out that the Water Industry TrainingCentre and its predecessor, the Water Training Centre, has beenengaged in providing quality training for operators of water andwastewater treatment plants for 31 years. I have been proud tohave been part of this for 29 of those years and privileged to seethe motivation of our water industry operators to accept thechallenge of training and personally develop their work andleadership skills over that time.

It therefore depresses me when I see comments that highlightthe lack of quality training in the industry, the dissatisfaction ofoperational managers regarding training quality, training coursesnot in keeping with regulatory and technological changes and thelack of trainers with acceptable water industry expertise. Nothingpositive in all of that.

The Water Industry Training Centre prides itself on thestandards set in its courses and assessment of operators. Feedbackfrom trainees indicates that these standards are meeting theirneeds in most cases and where constructive comments are made,we always use them to improve our techniques.

Our experience with operational managers would suggest thatin most cases they do have a good understanding of the trainingneeds of their staff and it is where these managers have a role inrecommending and arranging training, trainees not only attendbut are in a more beneficial position to qualify for a Certificate.This is achieved in part by our provision of Training Plans tooperations managers providing a clear training path toqualification. Many operational managers partner with us in thecollection of workplace evidence which we are very grateful forand it also provides an opportunity for these managers to play amore active and informed role in the training of their staff.

It disappoints me to hear comments regarding training coursesnot keeping up with changes in the industry. The Centre’scourses do cover traditional treatment processes as these are stillthe most common and conventional in our industry. It is vitallyimportant that trainees develop underpinning knowledge of thebasic concepts of treatment approaches if they are to optimiseplant performance. This requirement is reinforced in the contentof units of competency in the Water Training Package. Ourcourses are reviewed regularly and augmented with newer processvariations as they are implemented. Additionally, courses havebeen developed and incorporated into our range of options asthey are required. For example, Dissolved Air Flotation in theearly 1990’s and, more recently membrane and RO courses.

Where we develop training courses, considerable attention isapplied to ensuring that the content adequately meets theperformance criteria, skills and knowledge of the relevant Unitsof Competency in the Water Training Package.

Finally, we pride ourselves on having a high level of trainingexpertise in our organisation. Our staff all have significant

experience in the Australian water industry. Our trainers havepost graduate qualifications in engineering and chemistrytogether with assessment and training qualifications. Havingworked widely with clients throughout Australia, often on-site attreatment plants, has given us a high level of knowledgeregarding the roles and responsibilities of treatment plantoperators. Our significant voluntary involvement with the WaterIndustry Operators Association and the Australian WaterAssociation over many years has also been excellent personaldevelopment for our staff.

We aim to continue to provide quality vocational trainingservices to the water industry and it would be nice to see some ofthese publications identifying where there are positiveopportunities for operators to obtain training.

John ParkSeptember 2009

Editor’s Note

Thanks John. We are certainly aware that quality training isavailable and we would love to publish a list of organisations thatwe feel are quality providers. Unfortunately, in this day and age,we cannot. Keep up the good work.

L E T T E R T O T H E E D I T O R

LETTER TO THE EDITOR


On the 7th of February 2009, wildfireravaged towns throughout the state ofVictoria, damaging the environment andlocal infrastructure. The Kilmore WaterTreatment Plant (WTP) sustainedsubstantial damage to its electrical andcontrol room system and it was quicklyassessed as being beyond salvage.

The WTP services a combinedpopulation of approximately 7000 peoplewith an average daily consumption of3 ML/day. The high summer temperaturesmeant that it was extremely likely that thecommunities would be without potablewater. The task of rebuilding the plant atfirst seemed near impossible but with someclear thinking, in-house expertise and soundmanagement, the task was completedwithin the necessary time period.

Following a more detailed investigationon the Sunday afternoon, it was found thatwhile the control room and chemical dosingsystem were completely destroyed (seeFigure 1). Fortunately the Dissolved AirFiltration (DAF) filters, motors, backwashpumps, dispersion system, raw water supplyand most pipe work was still intact andserviceable.

All field wiring (415Vac, 240Vac, lowvoltage and instrumentation) cables were ingood condition. Although the cabling wasburnt at the cable entry point to thebuilding, it had suitable length on it to beserviceable which later would become a veryimportant aspect to the solution to thisincident.

To save water, Stage 4 restrictions had

been immediately introduced after the fire.

A limited supply from Yarra Valley

Water’s Wallan system had been

reconnected. With these steps in place it

was estimated that the water in storage

would sustain the system’s water supply for

approximately five days. Within five days

the 7000 people could be without drinking

water. This was not an option and could

not be allowed to happen. A solution to

the problem had to be provided within five

days. It also had to be sustainable and

possibly last 6-12 months. Not an easy

task.

The Plan

A number of ideas were considered, fromportable water systems to carting in waterby truck, but none were thought to beviable or sustainable for any length of time.Considering that the DAF system itself waslargely intact, the only solution was to tryto use it, rebuild the control room and startproducing water in the shortest timepossible.

As the Operations IT departmentmembers had detailed knowledge of theplant PLC code, SCADA systems andelectrical infrastructure, it was decided thatthe quickest option was to manage andresource the project from within GoulburnValley Water (GVW).

Work on the concept plan was startedimmediately on Sunday night. It was hopedthat this effort would dramatically increasethe chances of success and enable theprocurement of the necessary equipment tobe well on the way at the start of businessMonday morning. Over an eight hourperiod, various scenarios were discussed andalternatives considered. The Sunday nightsession was seen as the key to the success ofthe overall project. “There was a job to bedone: So let’s do it and do it well”.

The basic plan consisted of:

• Use a shipping container to house thetemporary control room containing themotor starters, PLC, interface cubicles,

E M E R G E N C Y W T P R E P A I R S

THE FIVE DAY CHALLENGEGreg Comer

Greg was awarded the Hepburn & Iwaki Prizes for the Best Paper Overall as well as the Actizyme Prize for Best Operator Paper at WIOA’s 2009 Victorian Conference.

Figure 2. The container “concept” summarised on a whiteboard.

Figure 1. The burnt out dosing and control room.

human machine interface (HMICitectSCADA), telemetry, UPS.

• The timing of restoration of power to thesite was unknown. Therefore a 300KVAdiesel generator would be required.

• Local electrical contractors would beemployed to investigate, test, label and getthe existing field cabling ready to beconnected to the new control room.

• The Corporation’s South WestOperations team, in conjunction withGVW treatment specialists, would arrangefor the replacement of the chemical dosingsystems.

A conceptual design for the layout of theshipping container (see Figure 2) wasdrawn up outlining where it would belocated onsite and where various cabinets(including junction boxes for the powerand control cables from the field) andmotor starters would be installed.

An important concept in the layout ofthe container was the ability to work onmore than one item at a time. This enabledsimultaneous construction phases to becompleted while others were put on hold ifparts were unavailable. As the week

progressed this decision was instrumental inachieving success.

The other important and equallyvaluable decision was to use the existingPLC code and CitectSCADA project thatwas operating before the fire. The PLCcode and CitectSCADA projects wereproven to work. It was thought that re-writing the code to a modified versionwould add extra time and produce errors.The Corporation’s change management

systems contained the latest backups ofthese projects and were easily obtained.

The next stage was to develop a detailedparts and equipment list. This coveredcabinets, cables, motor starters, PLCequipment, computer equipment, timberand a suitably sized generator. Thisinformation was placed in a spreadsheetand periodically e-mailed to vendorsthroughout the night/morning. Thisensured all the required parts would besourced and received as early as possible. Inaddition to this, the major vendors werecontacted Sunday evening to inform themof the situation so they would be fullyprepared for an immediate order earlyMonday morning.

With the design and procurement aspectscompleted, the attention turned todeveloping a time line for the construction,installation and commissioning phases ofthe project. Construction would begin firstthing Monday morning. Milestones wereset for various stages to be completed withregular update meetings to monitorprogress and assess whether extra resourceswere needed. A list of items for the criticalpath (show stoppers) were itemised with


Figure 3. Team members working sideby side in the shipping container.


contingencies put in place so thatobjectives could be achieved even whenexperiencing long delays. The core teamconsisted of five members of theOperations IT team and a maintenanceofficer from the Central water group toassist with general construction duties.

Day 1

The first task Monday morning was tobrief the other team members of thesituation and the task ahead. The containerarrived approximately 10.00am, ahead ofschedule, and was found to be already linedand insulated. This saved an enormousamount of time and allowed the realconstruction phase to begin. Initialconstruction tasks (measurements andlayout) were carried out in conjunctionwith finalising procurement of thematerials ordered in the late night planningsession. There were two local electricalwholesalers involved who greatly assisted inthis area. Lighting was installed in thecontainer as a priority so that work couldcontinue into the night. The remainder ofMonday saw the mounting of the cabinets,cable tray and some initial wiring. Ascheduled progress meeting was held tocheck on progress late that afternoon. Itwas agreed that the project was on targetand that some items that had not arrivedwould be on site first thing Tuesdaymorning. For the project to succeed it wasrealised that long hours were going to beneeded. Fatigue management issues werediscussed to reduce the risk of mistakes andaccidents. Team members were required toget at least 6 hours sleep a night.

Day 2

Tuesday saw the bulk of the constructiontake place. The main tasks carried outincluded continuing to mount the cabinetsand motor starters, cabling, setting up thelaptop for the HMI, air conditioninginstallation and cutting holes for the fieldwiring to enter the control room. The teamfollowed the layout drawn on the whiteboard at Sunday’s planning meeting,improvising where required toappropriately install the cabinets, motorstarters and cable tray for the large task ofinterfacing the field cabling.

The main item on the critical path forthe construction phase in Shepparton wasto adequately prepare the power andcontrol junction cabinets ready for the fieldequipment to be wired. Connectionsbetween the motor starters, power junctionbox and the power distribution board werealso carried out. The layout of thecontainer continued to be very importantwith up to five team members working

independently side by side (see Figure 3).After a second planned progress meeting itwas decided to gain the assistance of twoextra electricians to aid in wiring duties. Bythe end of day 2, progress was still on trackbut the enormity of the task was becomingapparent.

Day 3

Construction continued on Wednesdaymorning. Work was progressing well whichled to the decision to relocate the containerto Kilmore WTP on Wednesday afternoonand begin the next stage of wiring in thefield devices and a 300KVA generator.

Day 4

The wiring of the external field cables intothe interface cubicles continued onThursday along with the PLC cubicle. ThePLC input/output (I/O) wiring was a hugetask and the time needed wasunderestimated. This could have had thepotential to delay progress considerably. Asubset of the Operations IT teamconcentrated on this and made theimportant decision to test each I/O pointfrom the PLC code through to theCitectSCADA HMI as it was connected.While this was painfully slow the effort waswell worth it when it came tocommissioning the finished product. Thepre-built dosing system arrived and wasinstalled then interfaced to the controlsystem. Thursday proved to be the longestday with some 20 hours worked but theend was in sight and we had renewed beliefthe deadline could actually be met.

Day 5

The PLC wiring continued Friday morningand was still the main task to becompleted. All of the 415 and 240 Voltsupplies were connected enabling motordirection testing to begin and valveoperation to be tested. Some online waterquality instruments were interfaced to theHMI as a “nice to have” but not essentialto the overall task. Control signal cableswere all terminated and by mid afternoon,motors and valves were starting to operatein automatic mode. Figure 4 shows thefinished control room.

Late Friday afternoon, water was beingtreated in one filter. This water was thenused to backwash the second filter. Atapproximately 7.00pm Friday night theplant had two filters online producingreasonable quality water in automaticmode. At around 9:00pm on the Fridaynight, the inlet valve at the Kilmoretownship 16ML tank was opened and thetank commenced filling.

It was then time for a well earned beerand some sleep!! For all the team membersit had been a very rewarding experience butone that hopefully would not have to berepeated.

The Author

Greg Comer ([email protected]) isa SCADA Technical Officer withGoulburn Valley Water in CentralVictoria.


Figure 4. The finished control room.


O P E R A T O R T R A I N I N G

The exchange of experiences and the qualification of wastewatertreatment plant operators in Germany is organised by the DWA(German Association for Water, Wastewater and Waste). The roleof the DWA is to support the water and wastewater industries andto bring together specialists active in these fields. The Associationis a not for profit organisation. A major function of the DWA isthe provision of training and competencies for operators andprofessionals working in water and wastewater. This paper willdescribe the exchange of knowledge and experiences of operators ofWWTPs in the state of Baden-Wuerttemberg in the south ofGermany.

WW Treatment in Baden-Wuerttemberg, Germany

In 2004 there were 9,994 WWTPs operated in Germany, and96% of the inhabitants of Germany are connected to the sewernetwork. In Baden-Wuerttemberg, there are 1,026 operationalWWTPs with 99% of the inhabitants connected to a centralisedWWTP. Baden-Wuerttemberg has a population of 10.7 million,but due to the large amount of industry the total design capacity ofall WWTPs in Baden-Wuerttemberg is 21.5 million EP.

The WWTPs are divided into groups based on their BOD5

influent load, in accordance with the effluent requirements of theGerman government. Using the specific load of 60 g BOD5/person, the total load of the WWTP is calculated as an EP. Largerplants have to achieve better effluent results than the smallerplants.

Table 1 gives an overview of the size and type of wastewatertreatment processes in Baden-Wuerttemberg in Germany. Some83% of the WWTPs are activated sludge systems. Most of thesmaller activated sludge plants are operated with extended aerationto achieve a simultaneous aerobic sludge stabilisation, whereas theplants larger than 10,000 EP mainly use anaerobic digestion forthe stabilisation of the sludge.

In Germany WWTPs are mainly owned by the cities andtownships, and therefore in many small communities there is onlyone person responsible for the operation of the WWTP. Thismakes it very difficult for the operators to have an exchange withother professionals; hence the need for the DWA.

Based on geographical areas, the WWTPs are grouped inWWTP neighbourhoods. If there are more than 30 WWTPs in aneighbourhood, it will be divided into two neighbourhoods tokeep the groups small and effective. Due to the wide range of sizeof the WWTPs (50 to 1.2 m EP) and the different treatmentrequirements for the larger WWTPs, the plants larger than100,000 EP are connected into larger groups, to be able toconsider the special needs of both the smaller and the larger plants.

Figure 1 shows the groupings of neighbourhoods in Baden-Wuerttemberg.

Every neighbourhood has a facilitator and an operatorspokesperson. The facilitator is provided by the DWA to organisethe meetings and prepare and present new topics for the operators.The operator spokesperson represents the operators in liaison withthe DWA.

Some of the WWTPs are also connected in specialisedneighbourhoods to take into account particular needs relevant tothese plants. Specialised neighbourhoods are available for:

• Expert chemical staff

• Sludge treatment

• Trickling Filters

• SBR systems

• International Lake Constance neighbourhoods

There are three main events involving the WWTPneighbourhoods held each year.

1. Annual data evaluation

Early in the year there is a meeting of the whole neighbourhoodand the local water authority. The main focus of this meeting isthe evaluation of the previous year’s operating data, as well asdiscussion of technical and other problems of the operators. Thisday is organised by one of the operators at their WWTP. Typicallythis day starts with the inspection of the WWTP where themeeting is taking place. This allows time for discussion about theinstalled technology, effluent results and specific problems. After ashort break the data evaluation starts for all the plants. Thefacilitator compiles the data in software that allows directcomparison of the results of the last 2 years and between thedifferent plants (Figure 2).

Frequently the discussion is focused on a specific topic whichthe facilitator will introduce. Specific topics have been:

OPERATOR EXCHANGES IN GERMANY

Jörg Krampe

Figure 1. Allocation of the WWTP neighbourhoods in Baden-Wuerttemberg (DWA, 2008).


• Nitrogen removal efficiency

• Amount of infiltration water

• Energy consumption.

At this meeting, all of the reporting

requirements of the water authority are

determined, and relationships between the

operators and the water authority are

generally friendly and cooperative. At the

end of the day, the representative of the

water authority gives a short overview of

changes in legislation since the last

meeting, and forthcoming initiatives. The

facilitator gives an overview of changed

guidelines and specialised courses available

for operators in the coming year. Finally

the operator who will organise the next

meeting is chosen and the next date is

fixed.

2. Qualification day and excursions

This day is quite different because there

are no reporting issues to fulfil. This

gathering takes place in the summer time

and therefore this day can also be used forexcursions. In recent years, the excursionshave included:

• Visiting the production facilities of abelt filter manufacturer

• Visiting the rainwater and de-icingwater treatment at Stuttgart airport

• Visiting the WWTP sludge incinerationfacility at a local power station.

Apart from such excursions, thefacilitator delivers courses in topics theoperators have selected or that aresuggested by the DWA. Topics in recentyears have included:

• Operational problems with fine porediffusers – how to recognise and how tofix

• Enhancing the treatment process forphosphorus removal even if it is notforced by the water authority

• WWTP data evaluation and easy crosschecks against design parameters

• Checking and calibration of flow meters

Sometimes manufacturers are invited totalk about their latest developments, suchas flow meters, automatic samplers oroperational methods of analysis. There isalso the chance to talk about occupationalhealth and safety issues. This is one of thetopics championed by the DWA, whoprovide instructors and informationfocusing on this topic. Examples areshown in Figure 3 including safe seweraccess equipment.

Another recent example was a focus onwater quality in the receiving water body.A special bus equipped with microscopesand visual aids was organised for this day.Under the guidance of a biologist, thegroup examined the water quality of theriver Nagold before and after receiving theeffluent of the Wildberg WWTP (Figure4). Another important feature of the daywas a barbecue lunch for the group.

Such experiences give operators renewedmotivation and demonstrate what can be


Table 1. Size and type of WWTPs in Baden-Wuerttemberg (DWA, 2008).

Size (EP) No AS with AS with TF RBC Multi-stage Mechanical Lagoons not separate extended specified

stabilisation aeration

< 1,000 234 13 138 8 24 12 2 30 71,001 – 5,000 313 48 222 14 6 5 12 65,001 – 10,000 146 45 91 2 6 210,001 – 100,000 294 221 42 5 1 24 1> 100,000 39 34 2 2 1Total: 1,026 361 493 31 31 49 2 42 17

AS Activated sludge, TF Trickling Filter, RBC Rotating Biological Contactor.

Figure 2. Example graph for direct comparison of the operational results of theWWTPs

Figure 3. OHS courses for operators.


achieved by well-operated wastewatertreatment plants.

3. Review by facilitators and operatorspokespersons

After the results of the data evaluationof the neighbourhood days are evaluatedcentrally for all the neighbourhoods, theresults are discussed at a meeting offacilitators and operator spokespersons.There are also presentations of actualdevelopments in operations, legislationand research to ensure that everyone iswell informed about all importanttopics in wastewater treatment. All thepresentations at this day are availableelectronically, so that these cansubsequently be used at neighbourhooddays.

The concept of wastewater treatmentplant neighbourhoods is well received byall participations. It ensures thecontinuing development of plantoperators, and encourages questions andmutual assistance. For the operators it isalso very helpful to know that there is aWWTP not far away with special toolsin the workshop or stand by pumps orblowers. Possibly neighbouring operatorsare qualified in different topics (egelectrical, metal working or chemistry).

There is a significant benefit for thosetowns and cities whose operators haveaccess to this exchange platform betweenthe various WWTPs, and whereoperators can discuss problems with eachother, without having to pay aconsultant for every small problem. Andlast but not least, most of the facilitatorsgain benefit from networking with theoperators and seeing their problems firsthand.

Forty years of neighbourhood work inBaden-Wuerttemberg (Figure 5) showsthat this idea is a success story and canbe an example for other regions.

The Author

Joerg Krampe ([email protected]) is a principal wastewatertreatment engineer with SA Water.Previously he worked for 12 years as alecturer and researcher at the Universityof Stuttgart in Germany.

Editor’s Note

The implementation of similar groups inAustralia to facilitate formal andinformal interaction between water andwastewater treatment plant operatorswould certainly benefit operations in thiscountry.


Figure 4. Photos of the receiving water training course.

Figure 5. Gathering of Mentors on the occasion of the 40th anniversary of the WWTPneighbourhoods.

Have You Identified All The Hazards??

(From page 4) The answer: Golf balls from a neighboring golf course!

TopOpShotThere are many potentially spectacular photographs waiting to be taken in water industry operations. Some may alreadyhave been taken. WaterWorks would like to offer a prize for the TopOpShot submitted to WIOA in 2010. The best photoswill be displayed just as these are here in the December 2010 Edition. So send us photos you already have, or be onthe look out for a “good opportunity” during the year.


At the time of their construction, a finewire mesh was used to cover the ventilationholes in many of the concrete reservoirsused to store treated water in South EastQueensland. Due to the light weight natureof the material and its constant exposure tothe elements, the mesh had completelydeteriorated in the vast majority of cases(Figure 1). With this mesh no longer inplace, the reservoirs become exposed topotential water quality contamination issuesfrom both wind born debris and moreseriously, bird entry.

Inspection reports had been provided toSunshine Coast Water identifying threereservoirs with these very issues. SunshineCoast Water and their contractor AqualiftPotable Diving decided to approach therenovation process from a different angle.

Stainless steel security mesh (Figure 2)was selected for the replacement material, asit was rigid enough to cover the originalvent holes with minimal fixing and it wasalso fine enough to keep out insects, birdsand most wind born contaminants.

This stainless material is usually quiteexpensive, but many security doormanufacturers have off-cuts available andthey were happy to supply the smallerpieces at a fraction of the original price.

Large stainless steel washers were used oneach corner of the mesh panel (Figure 2b)and 8mm aluminium ‘knock in’ plugs withstainless steel drive pins were used to securethe panels.

One of the problems in replacing thescreens was gaining access to the ventilationholes that were often high above theground. Rather than work from the ground

up, it was determined that it would be moreeffective to do the work from the “topdown” using technical rope accessequipment and trained operators who couldcarry out this work safely and costeffectively. This eliminated the need forexpensive personnel lifting equipment andovercame the limited space around some ofthe tanks.

The operators used an SRT Oz Podrescue frame (Figure 3) to lower themselvesover the edge and carry out the drilling andpinning. This type of equipment is oftenused in cliff rescue scenarios and for high-rise window cleaning, as it can be easilymoved around when fully assembled and itonly requires minimal back stay anchoringto maintain stability.

A six to one rescue pulley system wasused to allow the operator to lower himself

over the edge, adjust his height and thenlock off (Figure 4). A secondary safety ropewas employed as a back up in case of apulley system failure. This was operated byone of the topside support personnel eachtime the operator was moving up or down.

By using a side rope (Figure 4) theoperator could be swung left and right bythe top side assistants to enable two meshpanels to be fixed on each drop over theside. After the first day and the usual‘process improvements’, the team werefixing up to thirty panels per day.Considering this was in fairly hot weatherconditions (mid January in Qld), it was a

W A T E R S T O R A G E

Figure 1. An unsealed ventilation hole in the upper wall of a reservoir.

VERMIN PROOFING POTABLEWATER STORAGES

Jai Josey and Peter Duzevich

Figure 2. (a) A piece of Stainless Steel security mesh and (b) the finished product.

Figure 3. Utilising the Oz Pod andadvanced roping techniques to assess theupper walls of a reservoir.


pretty good effort. The Oz Pod was pickedup by all three team members each time,shifted sideways and re-anchored as theteam moved around the reservoir wall.

Temporary anchors were drilled into theupper concrete walls on each reservoir, andthese were used to secure a back stay ropeonto the Oz Pod as it was moved aroundthe edge of the roof.

Ensuring water storage reservoirs areappropriately sealed (Figure 5) to preventcontamination by debris and vermin isessential to preserve the quality of the waterproduced by our water treatment facilitieswhile on its way to the consumer. In mostcases a relatively simple and inexpensivesolution can be found to fix these all toocommon problems.

The Authors

Jai Josey ([email protected]) is a supervisor with Sunshine CoastWater and Peter Duzevich is a projectmanager with Aqualift Potable Diving.

W A T E R S T O R A G E

Figure 4. The operator is held in position by a side rope fromhis harness (on right near hammer) leaving his hands free tocomplete his works effectively.

Figure 5. The Finished Product; mesh screens securedexternally over the ventilation holes.


A L G A E C O N T R O L

The Warragul WWTP is a 4 ML/d BNR

plant that has a single 30 m diameter

clarifier. Being out in the open, the clarifier

launder suffers from a lot of algal growth

which peaks in summer and is less extreme

in winter (Figure 1). Gippsland Water has

tried different cleaning strategies over the

years from a fixed brush arrangement

attached to the revolving bridge, to a

weekly clean with a pressure sprayer, to the

fall back mode of manual cleaning by the

operators (generally fortnightly). Each

method has its pros and cons – the fixed

brush arrangement doesn’t allow the algae

to really take hold but the brushes wear

down over time; the weekly pressure

sprayer clean never got rid of all the algae

and in the interim if the algae builds up

enough it can slough off and contribute to

suspended solids in the effluent. The same

issue is relevant for the fortnightly manual

clean. There are also the OH&S hazards

involved with working in the slippery

clarifier launder. As algae need access to the

sun to photosynthesise and grow, wedecided to try blocking the sunlight fromthe clarifier launder.

In November 2008, some crude coverswere installed in two sections on theclarifier to determine their effectiveness inlimiting algal growth (Figure 2). Theimpact of the covers was noticeable withina week and the difference between theshaded and unshaded sections wassignificant (Figure 3). During the regularfortnightly manual cleans, the shaded areas

could be cleaned right back tothe concrete whereas the exposedareas still had a slimy filmattached. There also appeared tobe little if any algal growth underthe covers. The residue that didcollect there seemed to be a thinfilm of pin floc carryover fromthe clarifier.

The covers have been in placefor nearly a year now and havecontinued to provide a barrier toalgal growth. Gippsland Waternow plans to provide a morerobust and permanent coveraround the entire clarifier in thefuture. It is envisaged that thefrequency of manual cleaning bythe operators will decrease toevery one or two months.

The Author

Adrain Harper ([email protected]) is a wastewater technologist withGippsland Water.

COVERING CLARIFIER LAUNDERSCONTROLS ALGAE

Adrian Harper

Figure 1. Typical algal growth twoweeks after cleaning.

Figure 2. Covers on the north side of theclarifier.

Figure 3. Difference between coveredand uncovered sections.


R E C Y C L E D W A T E R P L A N T

REVVING UP A RECYCLED WATER PLANT

Charlie SuggateCharlie was awarded the WITA Prize for the Best Paper Overall at WIOA’s 2009 Qld Conference.

As the keystone in Gold Coast CityCouncil’s Pimpama CoomeraWaterfuture Master Plan, thePimpama Treatment Plant has beendesigned to provide Class A+ recycledwater through a separate network fortoilet flushing and external use viapurple taps and fittings (Figure 1).

The Pimpama Treatment Plant islocated in a rapidly developing areabetween Brisbane and the GoldCoast. The plant combines awastewater treatment process basedaround a 5-stage Bardenphobioreactor, with a recycled watertreatment plant incorporating ultra-filtration and ultra-violet disinfection(Figure 2).

Stage 1 of the wastewater treatment plantwas commissioned in late 2008 with anominal design capacity of 17 ML/d. Theplant currently receives approximately4.2 ML/d ADWF – one quarter of thedesign flow.

A variety of operational challenges, someforeseen and others unforeseen, haveoccurred during the commissioning of thePimpama Wastewater and Recycled WaterTreatment Plant. These challenges havebeen overcome using both technicalknowledge and effective and consistentcommunication. As a result, the operations

team has benefited by gaining expandedknowledge and experience in addressingvarious issues that would otherwise rarelybe encountered during typical daily plantoperation.

Challenge 1. Seeding the Bioreactor

The process of inoculating the bioreactor atstart-up was the subject of much discussionwith a number of methods considered, eachrequiring pre-filling of the bioreactor withwater to approximately 30% of tank depth.These included the following:

• Addition of MLSS from local sourcefollowed by feeding of biomass withmanufactured food substrate beforeintroducing raw sewage.

- Pro: Saving on cost oftransporting entire requiredbiomass.

- Con: Risk developing biomassunaccustomed to raw sewagecharacteristic.

• Introduction of raw sewage thenallowing biomass to developnaturally.

- Pro: Cheapest option, with addedbenefit of developing a well adaptedbiomass.

- Con: Time required to developbiomass. Also likelihood of odour,foaming and sludge bulking.

• Addition of MLSS from local sourcefollowed by introduction of raw sewage.

- Pro: Fastest method to achieve BNR.

- Con: Logistically impractical totransport approx 200 tanker loads.

• Addition of dewatered sludge from localsource before introduction of raw sewage.

- Pro: Saving over cost of transportingMLSS.

- Con: Less viable biomass compared toMLSS due to extensive endogenousdecay.

Given that the plant was a greenfieldconstruction site, bioreactor seed sludgewould have to be sourced from anotherplant. The Coombabah and MerrimacWWTPs were the two most logical choices,producing significant quantities ofdewatered sludge daily with the addedadvantage that Merrimac would alsoprovide sludge containing extra phosphorusaccumulating bacteria.

The bioreactor was first filled with ClassB effluent pumped from the CoombabahWWTP effluent lagoons to a levelsufficiently above all submersible mixers, A-recycle pumps and OKI aerators. To avoidthe possibility of creating a septicenvironment and the associated odourissues, raw sewage was introduced one dayafter seeding had taken place.

A temporary concrete bund wasconstructed beside the bioreactor swingzone where seed sludge could be delivered

Figure 1. Purple water fittings designated forrecycled water use.

Figure 2. Pimpama treatment plant layout.


by the bio-solids transporting contractorbefore being applied directly to the aeratedswing zone by front-end loader.

To ensure even distribution of sludge wasoccurring throughout the bioreactor, MLSSconcentrations were tested regularly atvarious locations until 1200mg/L wasachieved. This took 5 days. During theseeding process and the following 2 weeks,the Specific Oxygen Uptake Rate (SOUR)was monitored closely to assess microbialactivity. Initially, SOUR results were verylow even into the second day of introducingseed sludge. Before the seeding processstarted, SOUR trials had shown thatbiomass within the dewatered sludge had asignificantly reduced viability incomparison to that of a healthy mixedliquor and further mortality was expected tooccur during handling and transport. As theSOUR results began to increase, so did therates of nitrification, so rapidly in fact thatcomplete nitrification was being achievedwithin 3 weeks from the day raw sewagewas introduced to the bioreactor and focuswas directed to improving denitrificationearlier than expected. At this stage, the ratesof enhanced biological phosphorus removalwere still not of primary concern.

Challenge 2. Excessive AerationCapacity

While the plant is receiving such lowloading rates, the use of an air relief blow-off valve (Figure 3) has been employed toavoid over pressurisation of the aerationheader piping and over aeration within thebioreactor. Rather than exhausting direct toatmosphere, possibly causing noisepollution, a section of 300mm header pipehas been submerged below the bioreactorsurface at aerobic zone 3 where excess air isreleased through perforations.

Although the oxygen transfer efficiency ofthis excess air is relatively low compared towhat would be delivered to this zone via theOKI aerator, the DO concentration doesstill increase as a result, so the aerationcontrol valve for this zone is left manuallyclosed for typical ADWF. The blow-offvalve’s automatic actuator modulates tomaintain the aeration header pressure set-point.

The current low oxygen demands in thebioreactor combined with the relativelylarge sizing of the aeration controlbutterfly valves to each zone makesoperating at ranges near the closedposition very finicky. Considerable effortwas spent during commissioning to tuneout the resulting sporadic DO fluctuationsfrom the PID control loops and throughcontinued experimentation a much

smoother DO profile across all zones hasbeen developed.

Challenge 3. Managing the SludgeAge

Maintaining a solids inventory in a 16.85ML bioreactor to suit an average dailydomestic sewage inflow of 4.2 ML andBOD of 250 mg/L would seem quite easy,however, regular interruptions to the sludgedewatering process due to variouscommissioning events saw the sludge agereach up to 60 days at times, double thetarget. Aside from being able to test the beltfilter presses at a higher solids loading rateand seeing the improved dewateringperformance offered by a sludge with verylow volatile suspended solids, the generalresult of running up the solids inventorywas negative and became a high priority torectify.

As the MLSS concentration increased upto 3000-4000 mg/L from a typical 2400mg/L, sludge settling characteristics wouldchange and often a pin-floc would develop.The resulting increase in clarifier effluentturbidity would then threaten to jeopardisecommissioning plans further downstream atthe media filters.

The dewatering process incorporates twogravity drainage deck (GDD) belt filterpresses that each have a feed capacity of80m3/hr, which when operated withoutinterruption are able to reduce the solidsinventory very quickly, however, experienceto date has shown that the sludge settlingcharacteristics will normally takeapproximately 1 sludge age to recover back

to optimum. These events are expected tobecome less frequent now thatcommissioning of the WWTP has beenfinalised.

Challenge 4. Chemical Dosing

Turn down capacity of methanol, alum andhypochlorite dosing systems continues to bea limitation. Methanol is dosed into thepost anoxic zone of the bioreactor as acarbon supplement for denitrifying bacteria.Although further improvements todenitrification are expected to be achievedvia continued fine tuning of aerationpatterns, methanol dosing will still berequired. Current dosing set points alreadyhave the pumps operating at minimumspeeds with low flow failures a regularoccurrence. Other options that will allowfurther turn down of the process are beingexplored.

Alum and hypochlorite dosing issues arerelated to the media filtration section of theRWTP. Alum is dosed at a flash mixerupstream of a series of four single mediafilters but the raw water quality comingfrom the secondary clarifier is such that verylittle alum is required, currently up to6.5mg/L, causing low flow failures similarto that of the methanol dosing system.

The media filtration section of the planthas provision for three different hypodosing points. First being at a flash mixerfor manganese oxidation upstream of thefilters, second for ultra filtration feed waterpost media filters and third at the entry tochlorine contact tanks (CCTs) also postmedia filters. The easiest solution to this


Figure 3. Aeration blow-off.

problem was to increase the dose rateupstream of the media filters so that anadequate chlorine residual would bemaintained throughout and allow bothdownstream pumps to be switched off.Recent alterations to HACCP parametervalues however, have since rendered thisoperational method inadequate andalternative approaches are now beingtrialled.

Challenge 5. Control system

During the wastewater plant startupprocess, SCADA software programmerswere required to continually change andadd new sections to the control system asother parts of the plant became available.This made it imperative to establish a highlevel of communication between theoperations team and commissioning staffassociated with SCADA systemdevelopment. Each series of developmentswould mean losing SCADA control of someor all of the plant for the time it took todownload the upgraded software. Withcooperation between both parties, anyunwanted software glitches that arose from

these upgrades, which happened almostevery time, were dealt with promptly andsystematically by the programmers.

A Profibus digital network has beeninstalled throughout both the wastewaterand recycled water treatment plants ratherthan a typical 4-20mA communicationsystem to provide easy access to devicealarming and equipment diagnosticsinformation. Given that most electrical staffand contractors have had limited experienceusing Profibus, familiarisation with thesystem is ongoing.

Due to the demands of meetingcommissioning milestones during plantstartup, much of the Profibus network wasinstalled without earthing to structures suchas cable trunking and hand-railing withVSD and Profibus cables also unshielded.Not only was the entire system vulnerablewithout earthing but most instruments onthe network became affected by signalinterference due to the absence of cableshielding, causing loss of plant controlduring worst cases. Much time and efforthas since been directed to eliminatinginterference with only intermittent events

still occurring in isolated sections of theplant.

Although the ultimate goal with any newtreatment plant is to construct a perfectexample of the latest technology thatoperates flawlessly from the day it is started,it is important to realise that this hasprobably never happened. By appreciatingthat defects are inevitable, and cannotalways be rectified overnight, and adoptinga positive approach towards cooperatingwith commissioning staff, GCW’soperations and maintenance personnel haveshown that startup problems can still becorrected to the desired standard at the endof the day.

The Author

Charlie Suggate([email protected]) is anOperator, with Gold Coast Water.

Editor’s Note

The scale and complexity of the PimpanaPlant is impressive. I’m sure Charlie wouldbe happy to show other operators aroundthe site.




This article is being presented not as ahighly technical one, but it is what it is, astraight forward description of what hashappened in the South East Queenslandwater industry during the last 12 months orso. The reformation processes that haveoccurred, and also the new vision for thefuture of the water supply industry in thisarea, can, and no doubt will be beneficial inthe long term. It is not the be all or end allof happiness and/or frustrations, but if wekeep focused on what is required of us as

individuals, together we will make it work.

As the old saying says:

You have to be serious about what you are

required to do, but you do not have to be

serious in how you do it.

Keep smiling.

I would just like to make it clear that the

content of this article is derived from my

experience in water treatment operations as

a “hands-on” worker from the coalface.

There is no intended malice towards any

individual, or “finger-pointing” towards anylevel of government.

Most readers would by now be aware ofthe recent Queensland State Governmenttakeover of raw water storages and WaterTreatment Plants throughout South EastQueensland. Many of the operational staffinvolved would share my opinion that it hasbeen a very bumpy ride to date.

Some of the staff of this new entity,Seqwater, started the same day as theQueensland council amalgamations tookplace, and others moved over on the 30thJune 2009. The transition has been dubbedby many in the industry as a hard and rapidtransition.

To make good decisions you need goodinformation, and in retrospect of what hashappened, there would perhaps have beenbetter or different recommendations if moretime was allocated to research and planning,prior to implementation. This may wellhave led to a smoother transition for staff.

Local Government amalgamations thatwere happening at the same time also had ahuge impact on the whole show. Thechanges people had to make, and still aredealing with is huge, and has had an effecton the overall structure in the entire Localand State Government scene.

Seqwater is now a large organisation thatis seeing rapid change. The following pointsare all impacting on the reform process:

• The operation and management of some24 referable dams and 47 WTPs

• WTPs that range from plain chlorinationto advanced treatment

• Internal water quality targets that cannotbe achieved at some sites withoutsignificant financial input for upgrades toinfrastructure. Some existing plants arenot even able to always meet all ADWGaesthetic parameters.

• The “bringing together” of many variedcultures from within the industry

• Changes to legislation that dictatestringent water quality guidelines

• Accountability and transparency to adegree that has not been seen previously

SEQ IN TRANSITION THEN AND NOW

John GranzienJohn was awarded the Actizyme Prize for Best Operator Paper

at WIOA’s 2009 Queensland Conference.

S E Q T R A N S I T I O N

Chlorine Dosing Site - We got a new loo,but made good use of the outhouse!!!

Somebody mentioned health and safetyso the outhouse had to go!!!!

THEN NOW

Pit Cover - Always wondered how longthe timber would last?

Firewood yet to be collected!

Chemical Dosing Site - Innovativebunding. Had to go, we lost a wheel!!

Much more appropriate. The operatorloves his plant now!!


• Strict health and safety requirements

• Training and re-training of staff to ensurecompetency levels are maintained

• Production of water that is not “onlysafe”, but also aesthetically pleasing

• New technology such as Ultra-filtrationand Desalination

• The introduction of “water-grid” systems.

The ADWG encompasses a catchment totap approach and Seqwater has toencompass a beach to bush approach, andensure that it caters for everything inbetween. Never mind we are where we are,we have to deal with the future based onexperience from the past.

Our Inheritance

In our area we have inherited a fewtreatment plants that have not been kept upto date. It is no-one’s fault, but in a smallCouncil, management can only do whatseems best, with what funds are available.The operators have often done more thanwhat was asked of them, and tried toimprove and implement what changes thatseemed necessary, to remedy any givensituation.

In particular, one WTP had received littleor no upgrades or improvements to help itsperformances in its 40-year plus lifetime.Small things were done over time to meetdemand, but water quality was left by thewayside. This was the way small countrytowns have done things for a long time, andmore focus had been put on infrastructureof roads and bridges along with wastemanagement (to a degree), than water andsewerage infrastructure. Water is the basis oflife, and safe drinking water should be theright of every Australian that is connectedto a reticulated supply in any town or city.

And Now

With what has been happening across SouthEast Queensland over the last 12 months orso, in the water reform process, all involvedhave had to put in extra effort to cope withthe increase in workload.

But, fruits of the changes, to meet therequirement set before us all, are starting tobe seen. With the extra support and helpthat has been offered by our new peers,process/quality control staff, catchment staffand management, but also not forgettingthe most important ones, the maintenancestaff, we are progressing reasonably well.

To date the amount of improvements inour area (Somerset) has been fantastic. Notsure if we were a particularly bad area tostart with, but I can recall a high-level staffmember in the organization saying at thestart, that Somerset has a number of risksfor us. That may have been the case, and it

sure has been the focus of numerableupgrades and rectifications.

Work Place Safety and Health issues havealso been progressively addressed, with greatprogress in rectification of work that hasbeen a blessing to the operators. Stairs havereplaced ladders, aluminium lids replacedrotten timber covers and gas chlorineinstallations have been upgraded to meetthe standards. There is a long way to go yet,but we also have come a long way.

Water quality improvements, the mainpriority of Seqwater, well what can I say butthis, things are happening big time and itcan only be for the better. The introductionof HACCP also will be beneficial over time,to ensure we can achieve the water qualityresults that are now mandatory. Rememberthese plants were managed mainly to meetdemand, but still not forgetting waterquality parameters being reached, with whatinformation and support that was given tothe operators. Again this new venture,comes with the help of our fellow waterindustry personnel, and we can only further

progress to the organization’s goal of theassurance of continuity of supply of a safe,aesthetically pleasing water-supply for all.

In closing I would like you all to perhapsjust spend a few seconds to ponder over aquote from Leonardo da Vinci: “Water is thedriving force of all nature”.

The Author

John Granzien ([email protected]) is Operations Supervisor (SomersetRegional Area) for the Seqwater.

Editor’s Note

What a fantastic change. I am sure the roadhas been bumpy but Seqwater can be proudof achieving this in such a short time. As aspecialist in operations and production ofsafe drinking water all I can say is the“Then” pictures are all too common acrossour country. Perhaps this story can act as aprompt to other councils and authorities tomake the changes. But of course the physicalchanges need to be supported with trainingand effective monitoring.

Chemical Dosing Site - Don’t ever saywe weren’t inventive!

Still don’t like the green colour as muchas the red and blue milk crate

Pump Facility - Made to last! Much more nicerer

S E Q T R A N S I T I O N

Valve Pit - Not sure what is supportingwhat?

Nice, with the new barbie plates.Handles too!

THEN NOW


Barwon Water provides a water supplysystem to the city of Geelong andsurrounding region with a population ofover 250,000. Up to 80% of the Geelongregion’s supply is traditionally derivedfrom the Barwon River catchment withthe remainder from the Moorabool Rivercatchment. In recent times, due toprolonged dry periods, up to 40% ofGeelong’s potable water supply has comefrom the Barwon Downs aquifer. Withclimate change continually having animpact on the amount of water able to beharvested from surface water storages andultimately groundwater resources, newways of utilising resources have had to beconsidered. This is where Aquifer Storageand Recovery (ASR) is being investigatedto see what benefits we may be able toachieve utilising this as a “new resource”.

What is ASR?

Aquifer Storage and Recovery (ASR) is atype of managed aquifer recharge wherebywater is injected into the ground andrecovered from the same bore at a latertime when required. The aquifer is used asa large underground storage facility intimes when surface water storages may befull and additional water is required to bestored for prolonged dry periods.

Depending on the end-use, the injectedwater may be sourced from stormwater,recycled water or excess surface water.Typically the water is stored in the aquiferfor a period of time which in-turnprovides additional treatment of the storedwater by way of pathogen die-off.

How does ASR work?

ASR works by the injection of water intothe ground by a series of injection bores.These injection bores are much likenormal groundwater extraction bores andlook much the same on the surface as atypical bore.

The most suitable type of ground forsuccessful ASR requires a coarsely gradedmaterial, typically gravel or sandy innature, confined between harder, moreimpervious material such as clay orbedrock. This allows the injected water tobe contained within a confining layer ofsuitable material and not allowed to escape

or flow away. The injected water forms a

reservoir “bubble” around the injection

well with some blending of water with

natural groundwater at the extremities of

the bubble (Figure 1).

Depending on the type of ground

conditions, a number of injection wells

may be required to allow a sufficient

injection rate and achieve the required

storage volume. In such cases injection

bubbles may overlap with each other to

form a single large reservoir of injected

water around the wells. Injected water will

need to be of sufficient quality so as to

meet environmental requirements

associated with mixing of groundwater,

prevent degradation of the aquifer and

potential “leaking” of the aquifer to

surface water systems.

When the injected water is required, the

injection wells become extraction wells to

extract the stored water out of the ground

for its intended use. Groundwater

observation bores would be used to

monitor the effect of water injected into

the ground and again when the water is

extracted.

What are the benefits of ASR?

ASR has a number of benefits overtraditional surface water type storages.These benefits include:

• Potentially large storage volumes withminimal surface footprints and noevaporation losses

• Ability to provide an additional level oftreatment through pathogen die-off over aperiod

• Generally lower infrastructure cost toconstruct in relation to similar sizedsurface storage

• Minimal environmental impactcompared to large surface water storages

ASR provides an alternative storage forwater that may have traditionally been“wasted” through lack of storageopportunities. Recycled water is apotentially continuous supply of waterthat currently has limited options to storelarge volumes for bulk use. Whilst most ofit may have a market for use during thedrier months for irrigation and watering,during winter this market subsides andexcess recycled water would not normally

Figure 1. Typical ASR Well Arrangement.

A Q U I F E R S T O R A G E A N D R E C O V E R Y

AQUIFER STORAGE AND RECOVERYTRIALS AT BARWON

Gwyn Hatton


be stored and subsequently wasted.Stormwater similarly would normally beavailable during wetter months when notrequired, as well as typically falling inshort, heavy bursts during summer wheremost would run off to waste. Stormwaterretarding basins in combination with ASRwould provide an opportunity to harvestthis previously unutilised resource.

Barwon Water ASR Research

With the realisation of stormwater andrecycled water as a valuable resource,Barwon Water has begun investigationsinto how the technology could be utilisedto provide a “new” water source andintegrated into its supply system. BarwonWater recognises that to combat climatechange, a diverse range of water supplyoptions is required to meet demand.

A number of sites have been identifiedas potential ASR sites in the Geelongregion with various end-use options beingconsidered. These sites include the newArmstrong Creek growth corridor to thesouth of Geelong, the Batesford quarryarea and adjoining Fyansford developmentarea to the West of Geelong and the JanJuc aquifer system to the south west ofGeelong.

Initial investigations centre on the JanJuc aquifer system, just to the north ofAnglesea. This area was chosen assignificant information about the groundconditions already exist in the area and isknown to contain suitable aquifer material.The area has two aquifers, an upperaquifer, which is the target aquifer for theinvestigations, and a lower aquifer, whichwill be accessed by the soon to becompleted Anglesea bore field. TheAnglesea bore field will provide up to7,000 ML/a of water to the Geelongsupply system from the end of 2009. Theupper and lower aquifers in this area areseparated by an almost impermeable layer,known as an aquitard.

The aim of the investigations in theJan Juc aquifer is to determine the abilityand suitability of the aquifer to storesufficient quantities of water to beconsidered for further development. Thestudies will determine any potentialenvironmental impacts and provide ananalysis on the potential for full-scaleimplementation.

The ASR research project is jointlyfunded and supported by theDepartment of Sustainability andEnvironment and comprises a four-staged approach to determining thesuitability of the aquifer:

• Stage 1 – Preliminary Aquifer

Characterisation whereby six observation

bores are drilled to a depth of

approximately 120m and a short-term

pump test is conducted at each bore to

determine aquifer transmissivity and initial

water quality.

• Stage 2 – Detailed Hydraulic

Assessment. A production bore is drilled

to a depth of approximately 120m and a

seven day pump test conducted to

determine aquifer performance. A further

three observation bores drilled to monitor

aquifer behaviour during pump test.

• Stage 3 – Aquifer Modelling &

Conceptual Design. A computer model is

generated from information gained from

Stages 1 & 2 to allow aquifer behaviour to

be modelled under various operating

scenarios.

• Stage 4 – Injection Trial and

Feasibility Analysis. A 7-28 day injection

trial whereby water is injected into the

aquifer to test the behaviour of the aquifer

and the injected water. From the injection

trial data, prepare a design and costing of a

preliminary injection bore field and assess

the feasibility of the project.

Future Directions

A number of possibilities exist for the useof ASR as a new water source for Geelong.For each of the three sites identified forresearch into ASR, potential injectionsource water may be derived from:

• Class A recycled water

• Stormwater

• Excess surface water

With potential end-use of extractedwater being:

• 3rd pipe use for garden watering, toiletflushing

• Industry or irrigation (sports grounds,golf courses)

Pending the outcome of the researchtrials and upgrade of the Black RockWater Reclamation Plant, ASR has thepotential to provide a significant resource.With up to 16,000 ML/a of recycled waterpotentially available, ASR could providethe means to utilise this precious resourcein the future.

The Author

Gwyn Hatton ([email protected]) is a Planning Officer, with BarwonWater in Southern Victoria.

Figure 2. Hypothetical ASR Concept.

A Q U I F E R S T O R A G E A N D R E C O V E R Y

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December 2009 - WIOAwioa.org.au/documents/waterworks/WaterWorksDec2009.pdf · 4 WATERWORKS DECEMBER...

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