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ACWS RESEARCH SUMMARY 2004 ‘Clean water, diverse aquatic ecosystems, and sandy beaches’ - our vision for the Adelaide coastal waters Towards informed management of Adelaide’s coastal waters

Towards informed management of Adelaide’s coastal watersAdelaide’s coastal waters form a complex network of living things and environments (an ‘ecosystem’), integral with the

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Page 1: Towards informed management of Adelaide’s coastal watersAdelaide’s coastal waters form a complex network of living things and environments (an ‘ecosystem’), integral with the

AdelaideCoastal

Waters

Study

A C W S R E S E A R C H S U M M A R Y 2 0 0 4

‘Clean water,diverse aquatic ecosystems,and sandy beaches’- our vision for the Adelaide coastal waters

Towards

informed

management

of Adelaide’s

coastal waters

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Australia has been described as a nation of ‘fringe-dwellers’ – most of us live near the coast. We arepassionate about our water sports, we embrace a‘beach culture’, and we identify with our aquatic icons.Brisbane has Moreton Bay, Sydney has the harbourand Bondi Beach, Melbourne has Port Phillip Bay andPerth has an unblemished urban coast from Fremantleto Scarborough and beyond. Adelaide is no different,and its residents are within easy reach of the coastalwaters of the Gulf St. Vincent.

Given our love affair with the marine environment, it isunfortunate we have treated it with such disrespectover such a long period. Our aquatic reserves havebeen used as refuse dumps since Europeansettlement. We have allowed untreated sewage, urbanand agricultural run-off, and industrial and commercialwastes to discharge into the waters we cherish somuch. ‘Assimilative capacity’ is a term that isfrequently used to justify our actions. While it is truethat the natural environment is remarkably resilientand has an incredible capacity to cope with thestresses we place upon it, there is a growingrealisation that this capacity is not limitless. Tell-talesigns of failing ecosystems have emerged along thecoasts, estuaries and embayments around the country.Declining water quality, algal blooms, loss ofseagrasses, coastal erosion, invasive pests, and alteredmarine communities are all part of the humanfootprint. The coastal waters off Adelaide are nodifferent, and are in fact showing signs of all of theseunwanted problems.

However, things are changing and natural resourcemanagers are turning to scientists to help understandhow our ecosystems work, what impact humanactivities are having on them, and to identify ways ofmanaging our natural assets in a sustainable andenvironmentally sensitive manner now and into thefuture. This is precisely what the Adelaide CoastalWaters Study is tasked to do.

The Adelaide Coastal Waters Study is an initiative ofthe South Australian government and with the financialbacking and support of a number of key stakeholders,it will undertake a range of detailed scientific studiesaimed at addressing significant environmental issuesassociated with the future management of the coastalwaters off Adelaide. As they become available, theoutcomes of the Study will contribute to an adaptivemanagement framework proposed for the region thatwill integrate research, management actions andmonitoring of the success of these actions. The Studyhas drawn together an impressive list of scientificexperts – mostly from local universities and researchinstitutions including Flinders University, the Universityof Adelaide, and SARDI together with CSIRO,University of Western Australia and local specialistconsultants. The Study will greatly benefit from theexpertise of a number of advisors including:Dr Graham Harris (CSIRO), Dr Graeme Batley (CSIRO),Dr Des Lord (UWA), Dr Dean Patterson (WBMOceanics), Dr Dennis Steffensen (AWQC),Mr Doug Fotheringham (DEH), and Dr Rod Connolly(Griffith Uni).

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ForewordForeword

Professor David R. FoxDirector, Adelaide Coastal Waters Study

This summary document has been compiled toprovide a simple, concise overview of the Study, theissues, and the research tasks. I encourage you toread it and to stay informed via the Study website:www.clw.csiro.au/acws/ over the next two years.

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Adelaide, the capital of South Australia, has one of the most pleasant coasts to befound anywhere in the world. Sheltered from westerly and southerly gales byYorke Peninsula and Kangaroo Island, and from the north winds by the bulk of theAustralian continent, the waters are generally calm, productive and inviting.

In summer, the beaches are busy, even at midnight in hot weather. Boating,whether in catamarans, yachts or dinghies, is accessible entertainment. In winter,the outlook still entices — numerous houses, apartments and restaurants line theshore. Beach fishers can be seen in all seasons.

Below the waterline, however, the coastal environment is causing managementconcern. The combined effects of wastewater discharges, run-off from urban andagricultural areas and sludge dumping over the last few decades have had anegative impact on the coastal environment. Former dense beds of seagrasses havedeclined; microscopic algae sometimes form obnoxious scums on the watersurface; biodiversity (marine plants, animals and microbes) may be being lost frommarine habitats; the marine environment appears unhealthy; and the waters may attimes be unsuitable for recreational use. In addition, sand movements are changingthe landscape of the seabed, exacerbating coastal erosion. These changes resultfrom the increasing population along the coast, and the existing managementarrangements for river discharges and wastewater outfalls. While they are notunique to Adelaide, being common to the waters off most Australian cities, theyare aggravated in the Adelaide coastal waters by the patterns of waves andcurrents in the embayments that give the waters their shelter.

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IntroductionIntroduction

SOUTH

AU

S T R A LI

A

AND RESOURCES SA

PRIMARY INDUSTRIES

TRANSPORT SA

MobilAdelaide Refinery

Supporting our LocalCommunity

CoastProtectionBoard

ACWSKey stakeholders

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In 2001, the South Australian Environment ProtectionAgency commenced the Adelaide Coastal WatersStudy to help address these problems throughimproved management practices. The study, which isalso being funded by other key stakeholderorganisations (see previous page), will generate adetailed understanding of the coastal ecology andenvironmental processes.

The area to be studied extends along the eastern sideof Gulf St Vincent from Port Gawler in the north toSellicks Beach in the south and adjoining rural land. Itwill examine the impacts from the catchment areasthat discharge into the Gulf, inland as far as thesource of the Onkaparinga River in the Mt Loftyranges, and 20 km out to sea.

Adelaide’s coastal waters form a complex network ofliving things and environments (an ‘ecosystem’),integral with the physical shape (morphology) of thebeaches and the seafloor near the coast, the waterquality, and the natural organisms that live in it. Thenarrow coastal strip between Port Gawler and SellicksBeach supports considerable human activity. In thesouth, surface water catchments have been clearedand are used for farming. Further north, there arefrequent wastewater and stormwater discharges intothe Gulf.

The Adelaide Coastal Waters Study objective andanticipated outputs provided clear direction and focusfor the research program and tasks. The objective isto develop knowledge and tools to enable sustainable

management of Adelaide’s coastal waters byidentifying causes of ecosystem modifications andquantifying the actions required to halt and reversethe degradation. This objective can be achieved bymeasuring the nutrients and other contaminants thatenter the Gulf from all sources, and to model thecirculation patterns of the coastal waters and thuspredict the effects of the contaminants on the coastalecosystem. Anticipated outcomes include newknowledge and understanding, options formanagement action, a program to measure theeffectiveness of management actions andcommunication of results.

The main functions and processes of the ecosystemare being investigated. Stage 1 of the Study definedthe problems and research tasks (2001-2003).

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New information to guide managementNew information to guide management

STUDY

SITESouthAustralia

Data supplied byEnvironmental and Geographic Information,Department for Environment and Heritage

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As results become available, they will be used toderive models describing the ecosystem and thefactors affecting it. The outcome will be a betterunderstanding of the coastal waters, which willprovide information to guide management decisions,for the benefit of both the Adelaide population andthe marine and coastal environments.

During the course of the research, several processmodels will be developed. For example, a‘hydrodynamic’ model will describe wave patterns,water circulation and the transport of dissolvedmaterials and particles in the study area.

Another model will describe the cycling of nutrientsfrom water and sediment into and out of marineplants and animals, and from place to place.(Nutrients are substances, such as nitrogen andphosphorous, which stimulate growth in living things.)

The teams will establish an ongoing program (orwhere necessary refine existing programs) formonitoring key aspects of water quality and the wholeecosystem. The monitoring will also give feedbackabout the effects future management actions mayhave.

As a result of monitoring and analysis, the teams willbe able to describe the contaminants and nutrientsthat are in (or likely to enter) the coastal waters,sediments and biota, together with their sources andlikely effects. They will be compiling a database ofresults and information, both historical and collectedin these studies, which will be accessible on theWorld Wide Web and on CD-ROM.

Finally, individual research results will be amalgamatedto develop tools to help managers organise, visualiseand assess the data and the outputs of the models.The tools should assist in decision-making processes.

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The first Stage 2 research tasks commenced in the spring of 2003, and thestudy is expected to finish early in 2006. South Australian and interstateresearch organisations and service providers have been engaged to undertakethe six major research tasks.

Task code Research/activity titleStage 2 Research tasksInput studies—quantity and qualityIS 1 Quantification of diffuse and point source terrestrial, groundwater and atmospheric inputs to the coastal watersEcological processesEP 1 Assessment of the effects of inputs to the Adelaide coastal waters on seagrass ecosystems and key biotaEnvironmental information systemsRS 1 Remote sensing study of marine and coastal features, and interpretation of changes in relation to natural and

anthropogenic processesPhysical processes and modellingPPM 1 Coastal sediment budgetPPM 2 Physical oceanographic studies in the Adelaide coastal waters, using high resolution modelling, field observations

and satellite techniquesEnvironmental monitoring programEMP 1 Environmental monitoring program—spatial/temporal design; statistical analysis; quality assurance and control

Stage 3 Synthesis and reporting tasksAMF 1 Development of adaptive management frameworkDST Development of decision support tools for managementDST MM 1 Development of a coarse resolution management model for the Adelaide coastal watersDST DB 1 ACWS database and spatial information system

Table 1: Research tasks for the Adelaide Coastal Waters Study

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Issue: Contaminants are entering the Adelaidecoastal waters: what are they, and whatquantities are coming in?Response: Input StudyThe Input Study comprises the group of sub-programstudies that will measure the volumes of, andcontaminants in, stormwater (the water producedthat runs off the urban landscape after a storm event),wastewater (treated sewage and treated industrial andcommercial wastes), groundwater and atmosphericfallout entering the coastal study area. Nutrients,inorganic substances, suspended solids (sedimentload), heavy metals, organic substances such aspesticides and other organic chemicals, andmicrobiological indicators will be assessed.

Five rivers and four wastewater outfalls, stormwaterdrains and groundwater discharges flow from theeastern side of the Gulf St Vincent into the Adelaidecoastal waters. Other materials enter the Gulf watersfrom the air — blown off the land or as depositssettling out from atmospheric pollution or in rainfall.

RiversOf the rivers, the Torrens, Patawalonga andOnkaparinga Rivers contribute most water, along withthe Port Adelaide River. Flows in the Torrens andPatawalonga rivers come mainly from urban sources,but the Onkaparinga rises in the Mt Lofty Ranges and

travels mainly through rural areas. The Field andGawler Rivers also flow into the Gulf, but contributeless water.

Flows into the Port Adelaide River and the associatedwetlands surrounding and connected to the BarkerInlet are predominantly derived from urban run-off.

To date, limited monitoring of water quantity andquality has been done on the small catchments andstormwater drains that flow directly into the coastalzone. However, the water comprising normal andstorm flows has been monitored to varying degrees inall the major catchments.

Essentially the studies will consist of continuing auditsof discharges in relation to rain events. Newmonitoring and sampling programs will be necessary,

although only selected catchments andstormwater drains will be monitored andsampled, apart from the Torrens,Patawalonga and Onkaparinga catchmentsthat will be investigated thoroughly.

No-one can expect to be on the spot tosample water quality and flow during each,or indeed any, major storm. Automaticrecording and sampling equipment will dothe bulk of the work, with some manualsampling to fill the gaps. There will bespecial effort to measure and samplestormwater flows and peak flows, becauseit is inevitable that regular measuring andsampling will miss many of the peak flows. Peak flows are of special interest becausethe catchments in the Adelaide area aregenerally small and streams respond rapidlyto major storm events. Furthermore, the

smallcatchments andstormwaterdrainagestargeted as partof this projectonly flow duringstorms.

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The research tasks (see table on previous page)The research tasks (see table on previous page)

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Wastewater The volume and quality ofwastewater can be partlycalculated from existingmonitoring data. The EPAmonitors annual volumes andcertain other aspects of theeffluent discharge emerging from(a) wastewater treatment plants(WWTP) in Water ProtectionAreas which deal with thewastewater of 100 equivalentpersons per day, and (b) WWTPoutside Water Protection Areaswhich deal with wastewater from1000 equivalent persons per day.

Previously, WWTPs were thought to be the principalreason that marine water quality was declining andseagrass and mangroves were dying. Therefore,environmental improvement programs wereestablished for a number of WWTPs in the Adelaidemetropolitan area. The questions now being askedare: what proportion of the marine environmentdegradation can be attributed to WWTP; what is therelative contribution from other sources; and,importantly, how should these be managed into thefuture?

For the Adelaide Coastal Waters Study, all WWTPdischarges that run directly into the sea in the studyarea will be included in the monitoring and auditprogram. The monitoring will also extend to WWTPsthat discharge into rivers, estuaries and other inlandaquatic systems that ultimately discharge into theAdelaide coastal waters. Knowledge of total quantitiesis not sufficient and will need to be augmented by dataon the daily, seasonal and inter-annual variabilitybetween discharges, as well as the concentrations ofthe components of the wastewater, especiallynutrients and toxicants.

GroundwaterGroundwater underlies the Adelaide plains in anumber of water bodies (aquifers) at varying depths.In these underground rock or sand formations waterflows fairly fast. All evidence suggests that thegroundwater is recharged in the Mt Lofty Ranges anddischarges out to sea. The sites, quality and quantityof groundwater discharges are not known, but thevolumes are likely to be substantial.

Some information about groundwater may beavailable initially from existing records and reports.

Water samples from bores will be collected andanalysed to fill any gaps. Information from thesesources will be used to select a site for fieldinvestigation, where instruments will be installed atthe coast and offshore, to measure the physicalproperties of groundwater flows, and to collectsamples for laboratory analysis.

Atmospheric inputsVery little is known about atmospheric inputs ofdissolved and solid material to coastal waters. Theycould be significant. Strong northerly winds carryingvisible dust blow in several times a year, especiallyduring late spring and early summer, and arecommonly followed immediately by cool fronts thatproduce rainfall. The Adelaide Coastal Waters Studywill be assessing the components of the dissolved andsolid inputs to the coastal zone that are contributedby atmospheric sources, and the relative proportionsdue to the north winds or daily inputs.

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The researchers intend to analyse samples from threesources. For more than 10 years, the EPA hascollected particles suspended in the air over Adelaide.The sampling equipment records the volume of airsampled, so that mass of suspended particles pervolume of air can be calculated. The researchers planto use data from past analysis of these samples and doadditional laboratory analyses on the stored samples.

The plan is to collect new dust samples in water-filledpans set out for 24-hour periods during dusty stormevents that have associated rainfall. Ten samples willbe collected this way. The researchers are alsoplanning two boat trips to collect samples fromcoastal waters during dust storms (four to six sampleson each trip). This will be done far enough from theshore to avoid mixing of the samples with sedimentfrom the shore stirred up by wave motion. All thesamples will undergo laboratory analysis.

What will the Input Study deliver?The Input Study will generate large amounts of datathat will be turned into information from which theresearch team will be able to map and describe therelative proportions of nutrients, toxic substances,materials both inert (inorganic) and from living things(organic), and sediments entering the coastal waters.Historical data will be augmented with new datagathered during the course of the study. Throughsuch an intensive data-gathering exercise, the teamshope to gain a clear picture of the inputs to thecoastal waters ecosystem, and they may also be ableto put historical data into context, extending theeffective time-frame of the study.

The knowledge gained from the Input Study willinclude the size and timing of inputs from major andminor catchments and small drainage basins. Theinfluences of land use and urbanisation in the variouscatchments should be visible in the relative loads ofnutrients, sediments and contaminants.

The teams will also identify sectors of wastewater(WWTPs versus road run-off versus stormwaterdischarges, for example) that are key contributors ofparticular types of contaminants. This information willhelp guide management strategies specific to thosesources (as opposed to expensive general pollutioncontrol measures currently being implemented). It isexpected that a clearer picture of the relativecontributions from wastewater and catchments atvarious parts of the coast will emerge.New ground will be broken in knowledge of

groundwater andatmospheric inputs to theAdelaide coastal waters. Theimportance of groundwatervolumes relative to other sources offresh or saline water should become evident, and theinformation gained about groundwater quantity andquality will be of great use for management purposes.And once they know the quantity of contaminantscontributed from the air is known, the researchteams will be able to estimate the total load ofcontaminants from all sources.

The likely outcomes of some management actionsmay be predictable, particularly in the light ofmanagement outcomes in similar situations in otherstates. For instance, specifically designed stormwaterponds and wetlands can control contaminant loads instormwater on its path to receiving waters (such asthe Gulf). For wastewater, alternative managementstrategies could include improving sewage treatmentor diverting outfalls directly into the sea far fromshore, retaining reclaimed water for use on land.

Issue: Seagrasses are being put under increasedstress. How are they reacting?Response: Ecological Processes Study The Ecological Processes Study seeks to find out thethings we don’t know about seagrasses and their wayof living (their ecology) in the Adelaide coastalenvironment. Seagrass beds form habitats for a rangeof species. They have been selected for intensiveinvestigation in recognition of their role as overallindicators of marine conditions. Changes in seagrassbeds can be useful triggers for management actions.Seagrass remains the major marine habitat type and iscommon along the coast and in the Port AdelaideRiver and Barker Inlet (below).

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Seagrass is the name given to any member of a groupof flowering plants that grow underwater - some ofthem up to the low to mid water mark and some indeeper waters. (Despite its name, seagrass is not akind of grass, although it resembles it in generalappearance).

Since the 1970s, the South Australian CoastProtection Board (CPB), and more recently the SouthAustralian Environment Protection Authority (EPA),have been concerned about the losses of seagrassesand the possible effects of the loss, both on biologicalprocesses and on physical processes such as sandmovement. Some areas that used to be dominated byseagrasses are now dominated by algae, particularlyGiffordia, a kind of brown seaweed, and Ulva, alsoknown as ‘sea lettuce’. The reduction of seagrass andits partial replacement with seaweed is a clearindicator of decline in water quality and the effects ofnutrient enrichment.

Some basic questions remain to be answered beforeeffective management strategies can be devised:

• What inputs are affecting the importantcombinations of species that include seagrassesand other plants, fish and other animals, in theAdelaide coastal waters?

• Why do seagrasses struggle to recolonise oncethey have suffered an initial loss?

• How does the nutrient cycle (of nitrogen,phosphorus, carbon, for instance) operate inseagrass ecosystems?

• Does the cycle vary from place to place orsituation to situation?

• What are the existing and tolerableconcentrations of metals and organic chemicals inthe life cycles of these biota?

The teams will be looking forcorrelations between theconditions in various parts ofthe Gulf and changes in the seagrassecosystems. Observations andexperiments by divers will complement observationsand experiments done in large seawater tanks (called‘mesocosms’) containing replicas of the coastal watersenvironment. Factors to be investigated includeturbidity, nutrients, toxic substances, low salinity andsedimentation. Stormwater, sewage and industrialdischarges are common sources of these factors.

Just because a toxic substance can be detected bychemical analysis of seawater, it does not necessarilymean it will affect sea creatures. The substance maynot be ‘bioavailable’ (that is, it may not be able to beabsorbed by plants and/or animals). Conversely, evenvery small, possibly unmeasurable, concentrations ofsome substances can stop a species breedingeffectively, or damage some other part of its life cycle,for example, reproduction. Therefore,ecotoxicological testing will complement the chemicalanalyses of water contaminants. The research teamwill measure the bioavailability of contaminants toselected organisms by examining their effects on theorganisms at a range of concentrations — that is, via‘bioassays’. Bioassays will provide data on the effectsof mixtures of pollutants and environmental variablessuch as turbidity, salinity and dissolved oxygen. Therewill be bioassays on several sensitive species becausetheir responses to the mixtures may differ.

Rather than just watch more of the seagrassecosystems disappear, the team will also find‘biomarkers’ in various marine plants or animals, asearly warning indicators of toxic effects. Monitoring ofbiomarkers (particular biochemical indicators) whichchange as a result of exposure to a substance shouldalso show up the effects of management actions thatreduce the loads of nutrients, toxicants or freshwaterdischarged into the sea.

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The knowledge generated from this task will bevaluable for the management of the Adelaide marineenvironment. At present, too little is known aboutthe complex coupled processes (physical, chemicaland biological) that operate there. Although othercoastal seagrass systems have already been studied(for example, off Brisbane, Melbourne and Perth), theAdelaide coastal waters and seafloor are different andthe ecosystem is thought to function differently as aresult.

Previous studies have indicated that seafloor sedimentis both a source of and a sink for toxic substances. Inthe Adelaide Coastal Waters Study, divers will surveythe seafloor and measure the way seafloorcommunities (plants and animals) vary from place toplace and through time. Then the teams will try andcorrelate the variations with concentrations ofnutrients, heavy metals and organic compoundsmeasured in the sediments of the seafloor. The thirdprong of this ‘triad’ approach will use amphipods(small prawn-like crustaceans) to show up toxicity inthe same sediments. The triad approach is arecognised method for making an integratedassessment of sediment quality in the marineenvironment.

Issue: Loss of seagrasses appears to have allowedmovement of the seafloor sediments and changesto the coastline. How did this happen?

Aerial photographic records since 1949 haverecorded an increase in bare sand on the coastalseafloor indicating a retreat of nearshore seagrassfrom the metropolitan coastline. In 1999, it wasdetermined that approximately 4000 ha of nearshoremeadows (or 50% of original coverage) had been lost.The loss of seagrass has exposed the loose seabedsediment to erosive forces that have at times stripped

and exposed the limestoneseafloor and created anenvironment that is readilycolonised by invasive marineorganisms.

Response: Remote Sensing Study The Remote Sensing Study is setting out to map theland surface of the coast and coastal seafloor featuresin detail. It will document changes that have occurredin the past, and investigate processes involved inenvironmental change in the study area.

The teams will use images taken remotely by aerialphotography and other airborne and spaceborne(satellite) instrumentation, but they will also usefieldwork to confirm the impressions gained from theremote imaging. The map will be one of the firstoutputs of the coastal waters study, and will be usedby all the teams when choosing their study sites.

The Remote Sensing Study team will also identify thethree-dimensional structure of the study area and itschanges through time, as shown on several years’aerial images. They will map the water circulationpatterns, including plumes from land-based discharges,and their dispersion and dilution. Seagrass beds andsediments can be seen on aerial photos from the late1940s onwards, as well as on modern remotelysensed imagery. They will be mapped through time, tomake a ‘seagrass decline curve’ that will be a basisfrom which to predict likely future seagrassconditions.

By investigating and interpreting wastewater andstormwater plumes, possibly via tracers such aschlorophyll (the substance that makes plants lookgreen), coloured organic substances or suspended

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sediments, the team will be able to assess how muchwater quality degradation is due to land-baseddischarges. For example, outfall plumes often carrysalt, nutrients and toxicants.

After this task is complete, the teams should have abetter idea about interactions between environmentalprocesses and marine and coastal features, whichmight have led to the present conditions.

Issue: What are the sources, sinks and fate ofsediments in the coastal system?In recent years, the natural seasonal changes in theAdelaide beach system have been adversely affectedby increased sand transport, both onshore andoffshore. Sand from areas previously protected byhealthy seagrass beds has moved into the active beachzone. At the same time, changes to the seafloortopography have altered the size and direction ofwaves that reach the shore and therefore the rates ofcoastal erosion.The Coast Protection Board (CPB) and the CoastalProtection Branch have investigated coastal erosion, whichaffects beaches and adjacent property.

Response: Coastal Sediment BudgetThe Adelaide Coastal Waters Study’s CoastalSediment Budget complements the CPB and Branchprograms. The task is intended to produce a balancesheet, showing how much sand is entering the beachzone from offshore areas, its particle sizes and whereit has come from, and where it is settling out. Withthis information, the CPB and Branch will be able toprepare more accurate sand budgets for the

metropolitan coast, assistingin the review anddevelopment of appropriatecoast protection strategies.

Looking to the future, the task teams will alsodetermine how the sand is being mobilised, and theirpaths from seafloor to beach. This part of the taskwill be based on concurrent sampling of sedimentsand water from 0 to 5 km from shore, measurementof water conditions at each sampling spot, and videoand still photography. The plan is to collect samplesthat best portray the likely minimum and maximumvariations (that is, mid-summer and mid-winter), alongwith opportunistic catastrophic events such as majorstorms or a spill at sea, during 2004–2005.

The results should allow predictive modelling that candeal with new situations developing after 2005 — forexample, changes in nutrient cycles, loss or gain ofseagrass meadows, increased boating activities orunusual storm activity.

Issue: The patterns of water movement in the Gulfare responsible for the movement ofcontaminants and changes in the seafloor andcoastline. Can we describe them?Response: Physical Processes and Modelling StudyLinking the Input and Ecological Processes Studies, thePhysical Processes and Modelling Study will determinethree dimensional patterns of water circulation,temperature, salinity, suspended matter and flushing inthe study area, in relation to ‘forcing’ (causal) factorssuch as winds, waves, tides and incoming flows.

This research task comprises four Subtasks. The firstof these will involve the collection of field data indifferent seasons of the year in order to analyse thedistribution and seasonal variability in water massproperties in the study area. Importantly, it will assistthe researchers to validate and verify the numericalmodels to be developed for the Study area. Theresearch team will also attempt to capture andmonitor dispersion patters during extreme eventssuch as periodic stormwater discharges.

Satellite imagery will be used to determine theexchange of suspended materials, such as sediment orchlorophyll-a, and dissolved contaminants betweenwater and beach, or freshwater plume and seawater,or water and seagrass bed, from season to season,under varying ocean and weather conditions.

This study will determine the influences of the near-shore region on coastal hydrodynamics, and the effect

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that this has for modelling and monitoring sedimentmovement. This aspect of the study will be conductedin consultation with the Coastal Protection Branch.

Issue: How should the coastal waters andadjacent environment be monitored in future?At the moment, Adelaide’s coastal waters aremonitored in separate programs that investigaterelatively small areas for relatively short periods oftime. The discharges from coastal WWTPs arechecked to ensure that the WWTPs comply withtheir licence conditions. The water quality at thecoast is measured at selected sites month by monthto ensure the waters are safe for swimming, surfing,boating, fishing and other recreation. But theenvironmental effects of the waters entering thecoastal area are not monitored, and monitoring doesnot continue over long periods of time. Response: Environmental Monitoring ProgramAll research tasks will contribute to theEnvironmental Monitoring Program. This veryimportant task will use information gathered duringthe course of the study to design a cost-effectiveongoing monitoring program that will integrate newand existing monitoring activities. It will ensure thatdata collection protocols are compatible amongresearch tasks, identify the parameters to bemonitored, and the monitoring sites and frequenciesrequired across all the programs. It will manage thedata collected by each research team, so the data arecollected in formats that can be statistically analysedand used across all the programs. It will coordinateand assist in the statistical analyses when the databegin to flow.

Issue: Can the outcomes of the study be put intoa form that will be useful to managers?

It is vitally important that theresearch tasks within theAdelaide Coastal Waters Studyimprove our understanding of thecoastal ecosystem and its function. The AdaptiveManagement Framework, Management Model andDatabase described later are particularly designed toguarantee that the study’s outcomes will contributeto the effective management of the coastal waters.The investigations that will take place within the studyare entirely driven by the need to provide informationfor the managers of the coastal environment — this isnot curiosity-driven research! Response: Adaptive Management Framework‘Adaptive management’ is a term commonly heardthese days, and one that will be important in thestudy, through development of the AdaptiveManagement Framework. Recognising that it is notpossible to completely understand and predict thebehaviour of complex ecosystems, managers for thestudy area will be acting on the basis of best availableinformation emerging from the study. They will beprepared to adapt and respond to the situations thatdevelop afterwards. The Adaptive ManagementFramework will produce an adaptive managementplan that will blend research, experimentation,monitoring and management actions into a cycle, somanagers can put the research outcomes intopractice, and the researchers in turn can learn fromthe resulting experiences of management.

Decision-making on behalf of such a complexecosystem as the coastal waters should be helped bydecision support tools and databases which canintegrate both the information from the eight newsources (the research tasks) and the informationavailable from numerous previous studies.

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Inputs - nutrients, toxicants, abiotics, biotics

Ecologicalprocesses and

ecosystemresponses

Adaptive management framework

Stage 2 task Predominately Stage 3 task

Catchmentand

hydrodynamicmodels

Environm

ental monito

ring andinfo

rmatio

n system m

anagement

MANAGEMENT

RESEARCHMONITORING

Adelaide

Making informeddecisions, not

knee jerk reactions. .Reduce nutrient

inputs. Multidisciplinary and integrated approaches, not just isolated research projects. Refocus research efforts in line with major nutrient sources and effects.

Providing positivefeedback, notcounting each seagrass blade.Report on effectiveness of nutrient management actions.

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Decision support tools help management workthrough various scenarios, plan for areas ofuncertainty, and assess the risks involved in likelymanagement actions. Separate tasks are intended toprovide the decision support software necessary, anda supporting database and information system for theAdelaide Coastal Waters Study.

There is an array of existing data from small-scale andfocused assessments and environmental monitoringprograms initiated during the past 30 or so years.

They describe aspects of theecology of the biota and theproperties of the coastal waters,but they are held by variousagencies and in the personal files of scientists.Obtaining a comprehensive picture is thus difficult. Itis expected that a well-designed, centralised,comprehensive database will marshal all the dataavailable, new and old, and also store the integratedoutputs and models that are about to be developed.

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Question: How do I find out how the Study is progressing and what is being learnt?Answer: Visit the study web site at: www.clw.csiro.au/acws The web site will include a searchable database of historical and study data as they come to hand (also to beavailable on CD-ROM), and a calendar of field research activities. (The calendar, in particular, should be useful ifyou are curious about the researchers’ sampling activities.)Question: Will I be able to read about the Study results and understand what they mean? Answer: Yes. During the study, the team will be distributing a regular newsletter,and they will be holding briefings, public meetings and workshops to keep thepeople of Adelaide in touch with developments. At the end of the study, the team will be publishing fact sheets that will discuss theconcerns of stakeholders and the management issues for the coastal waters, anddescribe the management implications of the research results. There will also be acomprehensive final report and database, as well as the models anddecision-making tools produced as part of the study itself, which will be valuableresources for the region’s managers and stakeholders. Question: Can I be confident that there are checks and balances in the study management, so the study stayson track and produces ‘the goods’?Answer: The CSIRO Environmental Projects Office (EPO) has been engaged by the S.A. Government to managethe Adelaide Coastal Waters Study on behalf of the contributing partners and stakeholders (Refer list of keystakeholders earlier in document). The EPO has an impressive track record of managing other similar studiesaround the country – most notably the Port Phillip Bay Environmental Study.

There’s also the scientific committee, a technical review group, and a steering committee all working together tocontinually oversee the study and its science.

• The steering committee consists of representatives of the partner stakeholders. It is guiding and directingthe whole study.

• An independent technical review group (chaired by Dr Des Lord), assisted by the scientific committee, isensuring that the research tasks are focused on the right questions; the questions that will get to the nub ofthe processes happening at the coast, to address the partner stakeholders’ issues and concerns.

• The scientific committee (chaired by Dr Graham Harris) comprises researchers from predominantly localresearch institutions and specialist consulting firms and it will be keeping a scientific eye on the researchmethods being used and the interpretation of the data. It will supervise the way the information from thevarious tasks is integrated and reported. This committee is also in a good position to identify situations thatmay develop where management intervention might be required to maximise the benefits of the researchprogram.

Keeping the people of Adelaide informedKeeping the people of Adelaide informed

‘City to Sea’ is an officialnewsletter being prepared eachquarter to communicate theprogress of the study to thestakeholders and the broadercommunity.

City to SeaCity to Sea

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This is a vital study whose results are expected to have a significant and on-going impact on the way thecoastal waters are managed now and into the future. The study provides an opportunity to solve, or atleast improve our understanding of, the mysteries of ecosystem decline in sheltered coastal waters. It is achance to link together the respected studies that have gone before but that may have been too small inthemselves to provide enough insight to the whole coastal waters ecosystem and its function.

The legacy of the study should be an extremely comprehensive database and excellent models describingthe dynamics of this complex environment and management tools for the future. But it is to be hopedthat the ultimate legacy will be healthy seagrass beds off Adelaide and improved water quality. In short, wewant the study to realise our vision for Adelaide, shared by stakeholders and study team alike:

‘Clean water, diverse aquatic ecosystems, and sandy beaches’

For more information contact:Mr. David EllisProject CoordinatorCSIRO Environmental Projects OfficeTel: (08) 8303 8420 Mobile: 0407 970 485 Fax: (08) 8303 8786 Email: [email protected]

Professor David FoxProject DirectorUniversity of MelbourneTel: (03) 8344 7253 Fax: (03) 8344 6215 Email: [email protected]

This outline of the Adelaide Coastal Waters Study is based on the large report, Adelaide Coastal Waters Study: Consolidated Stage 2and 3 Research Plans, available from the CSIRO Environmental Projects Office, Adelaide.

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In conclusionIn conclusion

C S I RO