water resource assessment: tatiara prescribed wells area ... · 4 primary industries and resources...

by

Michael CobbWater Search Pty Ltd

Keith BrownGroundwater Assessment

SEPTEMBER 2000

© Department for Water Resources South Australia, 2000This report is subject to copyright. Apart from fair dealing for the purposes of study, research, criticism or review

as permitted under the Copyright Act, no part may be reproduced without written permissionof the Chief Executive of the Department for Water Resources South Australia.

Water Resource Assessment:Tatiara Prescribed Wells Areafor theSouth East Catchment WaterManagement Board

PIRSA RB 2000/00036

South East CatchmentWater Management Board

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DEPARTMENT FOR WATER RESOURCESSOUTH AUSTRALIA

PIRSA RB 2000/00036

CONTENTS PAGE

EXECUTIVE SUMMARY 4

INTRODUCTION 6Background 6Nature and Scope of Work 6Study Area 7

Regional Hydrogeology 7Groundwater Management Areas 8

Groundwater Allocation Method (Licensing System) 8

HYDROGEOLOGY OF THE TATIARA PRESCRIBED WELLS AREA 9Geographical Setting 9Geomorphology 9Rainfall 9Surface Water Flows 9Local Hydrostratigraphy 10

Unconfined Aquifer 10Confined Aquifer 10

GROUNDWATER MANAGEMENT APPROACH 11History 11Management Zones 11

Unconfined Aquifer 11Confined Aquifer 11

THE MONITORING NETWORK 12Unconfined Aquifer 12

Current Monitoring Network 12Confined Aquifer 12

CURRENT STATUS OF THE WATER RESOURCES 12Unconfined Aquifer 12

Groundwater Flow 12Water Level Trends 13Salinity Distribution 13Salinity Trends 13

Confined Aquifer 14Water Level Trends 14Salinity Distribution 14

WATER DEMAND 14Unconfined Aquifer 14

Historical Demand 14Current Demand 17Future Demand 18

Confined Aquifer 18Historical Demand 18Current Demand 18Future Demand 18

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WATER BALANCE 18Unconfined Aquifer 18Confined Aquifer 20

POTENTIAL IMPACTS THE USE OR TAKING OF WATER FROM ONE RESOURCE MAYHAVE ON ANOTHER RESOURCE 20The Impact of Using Surface Water to Artificially Replenish the Groundwater System 20The Impact Taking or Using Groundwater from the Unconfined Aquifer May Have on the ConfinedAquifer and Adjacent PWAs 21The Impact Taking or Using Groundwater From the Confined Aquifer May Have on the UnconfinedAquifer 21

CONCLUSIONS 22

RECOMMENDATIONS 22

REFERENCES 22

FIGURESFigure 1 Prescribed Wells Areas in the South East Region Plan No. (200454–011) 24Figure 2 Geological provinces in the South East Region Plan No. (200454–008) 25Figure 3 Stratigraphic and hydrostratigraphic units of the Otway and Murray Basins

Plan No. (200454–009) 26Figure 4 Groundwater sub-areas in the Tatiara PWA Plan No. (200454–012) 27Figure 5 Schematic east-west geological cross section of the Tatiara PWA

Plan No. (200454–010) 28Figure 6 Location of current water level monitoring wells Plan No. (200454–013) 29Figure 7 Location of current salinity monitoring wells Plan No. (200454–014) 30Figure 8 Generalised water table elevation zones in the unconfined aquifer Plan No. (200454–015) 31Figure 9 Water level trends in the unconfined aquifer to June 2000 Plan No. (200454–016) 32Figure 10 Generalised salinity distribution in the unconfined aquifer Plan No. (200454–017) 33Figure 11 Salinity Trends in the unconfined aquifer to June 2000 Plan No. (200454–018) 34Figure 12 Irrigation activity distribution for 1998–1999 irrigation season Plan No. (200454–019) 35Figure 13 Tatiara Prescribed Wells Area. Proposed management zones for the Tertiary Confined

Sand Aquifer Plan No. (200454–058) 36

APPENDIX A Estimated irrigation requirements and crop area ratios for the Tatiara PrescribedWells Area 37

APPENDIX B Bore hydrographs and salinity graphs 39APPENDIX C Stock Water Use Consumption Figures 46

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PRIMARY INDUSTRIES AND RESOURCESSOUTH AUSTRALIA

REPORT BOOK 2000/00036 DME 00/0171

WATER RESOURCE ASSESSMENT:TATIARA PRESCRIBED WELLS AREAFOR THE SOUTH EAST CATCHMENT WATERMANAGEMENT BOARD

By Michael Cobb and Keith Brown

EXECUTIVE SUMMARY

In the development of a Water Allocation Plan forthe Tatiara PWA, the South East Catchment WaterManagement Board (SECWMB) appointedgroundwater consultants Water Search Pty Ltd andthe Department for Water Resources (DWR) toassess the water resources of the area. The studywas funded jointly by the SECWMB and the DWR.This study provides an overview of the currentstatus of the water resources in the Tatiara PWAand where applicable makes recommendations forits future management.

The Tatiara Prescribed Wells Area (PWA) islocated approximately 250 kilometres southeast ofAdelaide and covers an area of ~3500 km2. ThePWA can be divided by topography into a coastalplain to the west and the uplifted Pinnaroo Block tothe east referred to as the eastern highlands area.The two terrains are separated by a fault scarpreferred to as the Marmon Jabuk Scarp to the northof the PWA and the Kanawinka Fault to the south.The fault has no surface definition in the PWAbeing overlain by younger sedimentary deposits.

The main water resource is the regionallyunconfined aquifer contained within the MurrayGroup Limestone in the eastern highlands and thePadthaway Formation on the coastal plain.Groundwater flow in the aquifer is generally fromeast to the west. In the eastern highlandsgroundwater flows predominantly through theMurray Group Limestone. The depth to water canbe in excess of 40 metres, reflecting the elevatedtopography. Well yields from the aquifer rangefrom 50 to 200 L/sec. On the coastal plain theMurray Group Limestone is absent. Groundwater

flow in the unconfined aquifer continues mainlythrough the Padthaway Formation and theunderlying Bridgewater Formation. The depth towater on the coastal plain is generally less than fivemetres. Well yields can be up to 300 L/sec.

The unconfined and the underlying confinedaquifers are separated by a relatively thick, lowpermeability aquitard. For this reason the twoaquifers can be managed independently.

The confined aquifer also flows in a westerlydirection across the Tatiara PWA. Recharge to theaquifer is predominantly via lateral throughflow,possibly originating from the Dundas Plateau inwestern Victoria. Depth to the confined aquiferformation is generally more than 100 metres. Wellyields range between 10 and 20 L/sec. but wells canproduce fine sand when pumped.

The water resources of the Tatiara area wereproclaimed in 1984. This followed concerns raisedby the community that the observed irrigationexpansion was having a negative impact on thewater resources in the area. A subsequenthydrogeological study confirmed a long-termdecline in water quality in the densely irrigatedwestern portion of the region.

At the time of proclamation water licences wereissued on the basis of established irrigation activityor proposed development. In 1987, the TatiaraPWA was divided into a number of sub-areas (thesewere mainly Hundreds) and vertical rechargevolumes determined. The sub-areas were lateraltered to include the Border Zones. Thehydrogeological investigation confirmed that theannual water use in the Hundred of Stirling was

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approximately 25 000 ML. Rainfall recharge,however, was estimated to be only 19 260 ML.

In the Tatiara PWA there are currently 72observation wells in the water level monitoringnetwork of which, three of the wells monitor theconfined aquifer. There are two salinity monitoringnetworks in the PWA, a government operatednetwork and a private irrigation network. Thecombined total of observation wells in the salinitynetworks number 151, two of which are used tomonitor the confined aquifer. Generally thenumber of observation wells in the monitoringnetworks are acceptable for the Tatiara PWA. Thenetwork could be improved by increasing thesalinity network in the southern portion of thePWA and by adding one or two water levelobservation wells in the Hundred of Shaugh.

In the unconfined aquifer water levels in the north-western portion of the PWA, particularly Sub-area7, are declining at a rate of more than 5 cm/yr. Inparts of the same area, the salinity of thegroundwater exceeds 7000 mg/L and is increasingby more than 100 mg/L annually. The majorfactors responsible for the salinity increase areconsidered to be groundwater recycling and overextraction.

Above 7000 mg/L TDS yields for lucerne seed, themajor crop grown in the area, will decrease. Thehigh groundwater salinity limits the options foralternative crops to be grown in the area shouldlucerne become uneconomical.

In the eastern highlands hydrographs are generallyshowing a slight long-term rise in the water table.Associated with the rise is an increase ingroundwater salinity and these phenomena areattributed to clearance of native vegetation by earlyEuropean settlers.

In the confined aquifer one of the hydrographsshows a slight long-term increase, while anothershows a slight decrease. The third shows noappreciable change. The rising and fallingpotentiometric head are most probably a result ofchanges in overburden pressure related tocorresponding water level changes in theunconfined aquifer. Salinity of the confinedaquifer generally ranges between 1200 and1300 mg/L.

The total allocation for the Tatiara PWA in the1998/1999 irrigation season was 89 351 ML. Totalgroundwater usage was estimated to be 63 442 ML

which equates to 71% of the total allocation. Intwo sub-areas, Zone 8A and Part Zone 9A smallquantities of water are available for allocation.There is only one user of the confined aquifer in theTatiara PWA.

In 1997 the allocation in Sub-area 7 (Hundred ofStirling) was voluntarily reduced by 35% to bringthe allocation in line with the estimated rainfallrecharge volume for the area. At the same timecrop area ratios were altered for lucerne seed.

A water balance was determined on a sub-areabasis for the Tatiara PWA. The results of the waterbalance would suggest that, save for a decline instorage as a result of falling water levels in thewestern portion of the PWA, the area is more orless in balance. Uncertainty in the groundwaterparameters used in the balance may explain thisdiscrepancy.

Of most concern is the long-term sustainability ofthe unconfined aquifer water resource in thewestern portion of the Tatiara PWA.

The water use figures probably underestimate thetotal groundwater extracted from the aquifer bymany times. This is particularly so when floodirrigation practices are employed.

In the Tatiara PWA, the impact taking or use ofwater from one resource may have on the quantityand quality of water of another resource wereassessed in the following situations:

• the impact of using surface water to artificiallyreplenish the groundwater system.

• the impact taking groundwater from theunconfined aquifer may have on the confinedaquifer.

• the impact taking groundwater from theconfined aquifer may have on the unconfinedaquifer.

Recharge to the unconfined aquifer via preferentialflow paths, such as runaway holes or dischargewells, is fairly common in the Tatiara PWA. Whileboth supply the unconfined aquifer with a valuablesource of water, the discharge wells are designedmainly to reduce surface flooding during seasonallyhigh levels of rainfall. Distinguishing betweennaturally occurring recharge systems and man-madesystems can be subjective. A study into pointsource recharge into one of the major swamps in

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the area showed only localised impacts on the waterresource of the unconfined aquifer, so it is unlikelythat any man-made well used to artificiallyreplenish the aquifer would show any significantimpact.

A relatively thick, low permeability aquitardseparates the unconfined and confined aquifers inthe Tatiara PWA. The interconnectivity betweenthe two aquifer systems is consequently reasonablylow. It is unlikely therefore that taking ground-water from one aquifer would have any majorimpact on the other.

It is possible that extraction from Sub-area 7 isimpacting across the boundaries of watermanagement sub-areas. There is a long-termdecline in Sub-area 7 of more than 5 cm/yr. Similardeclines are also evident in the northern portion ofSub-area 3 (the Hundred of Willalooka) and thenorth-western portion of Sub-area 2 (the Hundredof Wirrega). It is unclear whether this is anexpansion of a drawdown cone emanating fromSub-area 7 or the declining water table in the othersub-areas is a localised phenomenon.

In the long-term, a decline in groundwater quality isexpected down-gradient of the densely irrigatedarea in Sub-area 7. This would occur outside theTatiara PWA with the largest impact expected inthe eastern portion of the Hundred of Laffer andpossibly the Tintinara-Coonalpyn moratorium area.

INTRODUCTION

BACKGROUND

There are five water management zones, coveringan area of almost 20 000 km2, in the South Eastregion of South Australia (Fig. 1). The South EastCatchment Water Management Board (SECWMB)are in the process of preparing Water AllocationPlans for each of these five Prescribed Wells Areas(PWAs).

Under the Water Resources Act (1997) there is arequirement that in the preparation of each WaterAllocation Plan, consideration must be given toSections 101 (4) (b) and 101 (4) (e) of the Act.That is the Plan must:

! “include an assessment as to whether thetaking or use of water from the resource willhave a detrimental effect on the quantity or

quality of water that is available from anyother resource”: and

! “assess the capacity of the resource to meet thedemands for water on a continuing basis andprovide regular monitoring of the capacity ofthe resource to meet those demands.”

In order to fulfil this requirement, the Departmentfor Water Resources South Australia (DWR), andgroundwater consultants Water Search Pty Ltd,have been jointly appointed by the SECWMB toassess the water resources of each PWA in thecontext of the above sections of the Act.

NATURE AND SCOPE OF WORK

This report provides an overview of the waterresources for the Tatiara PWA and appliesspecifically to the principal term of referencenamely addressing Sections 101 (4) (b) and 101 (4)(e) of the Act.

To meet this commitment each assessment of aPWA includes:

! a general description of the groundwaterresources for each of the aquifers in the PWA

! for both the unconfined and confined aquifers:

• the management approach adopted for thesustainable use of the resource (generallyreferred to as Permissible Annual Volume) anda description of the manner in which thesustainable limits of use can be determined.Where separate management areas exist withinthe PWA, the adopted limits of sustainablegroundwater use need to be tabulated. Theassessment should identify any data deficienciesand requirements for future investigations.

• the historic demand (in terms of use) andcurrent demand (in terms of the level ofallocations and use) in each of the managementareas within the PWA, by major categories(irrigation, industrial, municipal, stock anddomestic supplies).

• the likely future demand for groundwaterfrom this resource in the PWA, where possibledifferentiating between major use categories(irrigation, industrial, municipal, stock anddomestic supplies).

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• an assessment of whether the taking or usefrom either aquifer will have a detrimental effecton the quantity or quality of water that isavailable from any other water resource, bothwithin and outside of the PWA, including adescription of the likely nature and extent of anydetrimental effects.

• an assessment of the current condition ofthe groundwater resources of both aquifers,taking into consideration available groundwatermonitoring data to determine the capacity ofboth aquifers to meet the demands identified, ona continuing basis. This is to includerecommendations for management interventionin areas where it is considered that the resourcemay not have the capacity to meet futuredemands.

• an assessment of the adequacy of thecurrent groundwater monitoring network in thePWA for monitoring the capacity of theresource to meet demands, includingrecommendations for any additional monitoringrequirements.

The project brief does not include an environmentalassessment of groundwater dependent ecosystemsas this is being undertaken by a separateconsultancy.

STUDY AREA

Regional Hydrogeology

Geologically the South East region liespredominantly within the Gambier Embayment ofthe Otway Basin. The Tatiara PWA however islocated on the south-western margin of the MurrayBasin. The two basins are partially separated by abasement high, of the Padthaway Ridge (Fig. 2).Both basins are still however hydraulicallyconnected. With the exception of the GlenelgRiver, which lies predominantly over the Stateborder in Victoria, there are no extensive suppliesof good quality surface water flows in the SouthEast. Groundwater, therefore, provides the mainwater resource for the region. While primarily usedfor irrigation, the groundwater is also used forindustrial, recreational and stock use, and forsupplying municipal water to a number of townslocated in the area.

The South East region is characterised by severalextensive low-lying flats interspersed with a seriesof north-west trending remnant sand dune ridges.

Beyond the Kanawinka Fault (east of Naracoorte)the topography rises into higher inland plains whichextend into western Victoria (maximum elevationof ~300 metres).

The geological and hydrogeological units of theOtway and Murray Basins are easily comparableand reflect a similar basin evolutionary history.The names of the stratigraphic andhydrostratigraphic units do however differ. Acomparison of the nomenclature for the two Basinsis shown on Figure 3.

In both Basins groundwater flows through twomajor aquifer systems: a regionally unconfinedlimestone aquifer and an underlying confinedquartz sand aquifer. The two aquifers are separatedby a low permeability aquitard usually made up of adark brown carbonaceous clay. The aquifers arehydraulically connected, but the degree ofhydraulic connectivity between the two aquifers ispoorly understood and is currently an area of activeresearch.

The upper, unconfined aquifer is the mostextensively used of the two aquifers. However therecent introduction of water management policieswhich effectively caps it’s use, coupled with poorgroundwater quality in the aquifer in some areas,has resulted in increased interest in the confinedaquifer as a water resource.

The regionally extensive unconfined aquiferconsists mainly of calcareous sandstone andlimestone deposited during the latter part of theTertiary Period through to the Quaternary (~ 30million years ago to present). It incorporates theGambier Limestone (referred to as the MurrayGroup Limestone in the Murray Basin),Coomandook, Bridgewater, and PadthawayFormations.

Recharge to the confined aquifer relies ondownward leakage from the overlying unconfinedaquifer. This occurs in the eastern margin of theregion. Here the water table in the unconfinedaquifer is higher than the potentiometric head in theconfined aquifer hence there is potential fordownward leakage (recharge) to the confinedaquifer. To the west and south of the region thehead distribution is reversed and there is thepotential for upward leakage from the confinedaquifer to the unconfined aquifer.

The confined aquifer consists of non-calcareousquartz sands, interbedded with dark brown

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carbonaceous clays. Together these units make upthe Dilwyn Formation (referred to as the RenmarkGroup in the Murray Basin). Deposition of theDilwyn Formation occurred during the early part ofthe Tertiary Period.

The confined aquifer, for management purposes, istreated regionally as one aquifer, but it is in realitya complex multi-aquifer groundwater system. Lackof data means there is little real understanding onthe hydraulic interconnection between these sub-aquifers. The confined aquifer is very thin orabsent in much of the northern margins of theSouth East.

Groundwater flow, for both the unconfined andconfined aquifer systems, originates from thetopographic high of the Dundas Plateau located inwestern Victoria. From there, the groundwaterflows radially westward and southward to the coast,and northwards to the Murray River. The rate thegroundwater moves through each aquifer dependson its hydrogeological properties. Higher rates ofgroundwater flow are most evident in the upperunconfined aquifer where a secondary porosity hasdeveloped.

There are a number of major faults in the area. Thetwo most prominent are the NW trendingKanawinka Fault and the W–NW trendingTartwaup Fault (Fig. 2). Kanawinka Fault has apronounced lineament and is downthrown to thesouth-west. The west-northwesterly trendingTartwaup Fault is expressed as a monoclinalstructure. Downthrow is generally in a southerlydirection. The potentiometric surface of bothaquifers indicate a significant steepening of slopeimmediately up-gradient of each Fault. While theeffect faulting has had on groundwater flow can beinferred from the head gradients in both aquifers,the mechanisms responsible for this are poorlyunderstood.

The salinity of the groundwater of the unconfinedaquifer ranges from ~ 500 mg/L in the south, tomore than 7000 mg/L in the north. Groundwatersalinity in the confined aquifer system is typicallyless than 500 mg/L in the south, around MountGambier, but increases gradually northwards toover 10 000 mg/L as the aquifer thins north ofKingston.

The climate of the South East region is typified byhot, dry summers and cool wet winters. Annualrainfall ranges from more than 800 mm in the southto about 450 mm in the north. Potential

evapotranspiration increases from about 1400 mmin the south to about 1800 mm in the north.Precipitation exceeds potential evapotranspirationusually from May to September. Recharge to theupper unconfined aquifer generally occurs duringthis period.

Groundwater Management Areas

The South East Catchment Water ManagementBoard was established under the Water ResourcesAct 1997. The Board is responsible for themanagement of the water resources in the SouthEast region. It is under the Act that the waterresources are prescribed. In total there are fivePrescribed Wells Areas in the South East region.They include the established PWAs of Padthaway,Tatiara, Comaum-Caroline, and Naracoorte Ranges(these were proclaimed/prescribed under previousWater Resources Acts) and the recently prescribedLacepede-Kongorong PWA (Fig. 1). To allow formore effective management of each PWA, thePWAs have been subdivided into zones, andsometimes sub-zones.

The other piece of water resource legislation that isimportant to the region is the Groundwater BorderAgreement Act (Governments of South Australiaand Victoria) 1985. This Act covers the waterresources of the 40 kilometre wide strip that iscentred on the South Australian and Victorianborder. The South Australian/Victorian BorderReview Committee comprising representativesfrom both States is responsible for administeringthe water resources along the Border Zone.

Formal boundaries have yet to be established forthe confined aquifer in the South East region. Forthis report the confined aquifer boundaries wereassumed to be those proposed by the SA/VicBorder Technical Review Committee (Fig. 13).

GROUNDWATER ALLOCATIONMETHOD (LICENSING SYSTEM)

For the purposes of managing the unconfinedaquifer, groundwater is allocated on the basis of theestimated average yearly vertical recharge to thewater table. The underlying principle behind thisapproach is that lateral throughflow is maintainedin the aquifer, thereby allowing any saltsaccumulated during the recharge process to beflushed down-gradient. Average rainfall, soil type(and its properties), land use (and vegetationcover), and water level changes (both seasonal and

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long-term) are taken into consideration in thevertical recharge calculation.

The sustainability of the resource is thereforedefined as total vertical recharge to each PWA (ie.the Permissible Annual Volume (PAV)).Theoretically, licences would then be issued to takewater up to the limit of the PAV. Allocation of awater licence is based on area and the irrigated cropwater requirement relative to a reference crop(Crop Area Ratio system). The area based systemdoes not take into account irrigation inefficiencies.It assumes any excess water pumped from theaquifer, and not used by the crop or lost toevaporation, percolates back down into theunconfined aquifer.

The same water allocation system is used for theconfined aquifer. However the excess irrigationwater does not return to the confined aquifer but tothe unconfined aquifer. Therefore this methodconsiderably underestimates water use from theaquifer.

HYDROGEOLOGY OF THETATIARA PWA

GEOGRAPHICAL SETTING

The Tatiara PWA covers an area of approximately3500 km2 and includes the Hundreds ofCannawigara, Pendleton, Senior, Shaugh, Stirling,Tatiara, Willalooka, and Wirrega and a small partof McCallum that lies within the 20 kilometreborder strip (Fig. 4). The northern part of Zone 7A,all of Zone 8A and the southern part of Zone 9A ofthe Border Zone are located inside the TatiaraPWA. Both the major towns, Keith in the west ofthe PWA and Bordertown in the east, lie on themain Adelaide-Melbourne highway that runsthrough the Tatiara PWA in a southeast direction.

GEOMORPHOLOGY

The Tatiara PWA can be divided into two discreteland-forms, a low-lying coastal plain to the westand the uplifted highlands of the Pinnaroo Block tothe east. Separating the two terrains is the MarmonJabuk Fault scarp in the north and the KanawinkaFault in the south. In the Tatiara PWA the faultscarp is covered by a remnant dunal ridge that risesapproximately 50 to 60 metres above the plain.

The coastal plain consists of a succession ofstranded coastal dunes that run sub-parallel to thepresent coastline. The ridges are separated by aseries of low-lying interdunal flats. Underlying thecoastal plain sediments is the regional basementhigh of the Padthaway Ridge. The basementconsists of early Palaeozoic igneous rocks andmetasediments that outcrop at the surface at anumber of locations throughout the coastal plain.

The surface of the eastern highlands consists ofundulating plains which increase in height to thenortheast, reaching a maximum altitude of 130 mabove sea level. Overlying the undulating plainsare remnant sand dunes and E-S-E trending sandsheets.

RAINFALL

The climate in the Tatiara PWA is typical of theSouth East; hot, dry summers and cool wet winters.The average annual rainfall in Bordertown (1881 topresent) is 488 mm. In Keith the average rainfall(1906 to present) is slightly less at 469 mm. Thelower rainfall in Keith is consistent with adecreasing rainfall trend from south to northobserved in the South East region. The annualpotential evapotranspiration is approximately1700 mm (Stadter et al., 1995).

SURFACE WATER FLOWS

There are two ephemeral water courses in theTatiara PWA namely Tatiara Creek and NalangCreek. Both drain from the elevated PinnarooBlock in the east. The catchment areas for thesecreeks are more than 500 km2 and extend intowestern Victoria. Tatiara Creek discharges intoPoochers Swamp and Scowns runaway hole, whileNalang Creek discharges into Mundulla swamp.

The flow in the creeks can last anywhere from afew days to a few weeks. Total annual flowvolumes in the Tatiara Creek ranged from 1300 to20 000 ML between 1987 to 1991 (Herczeg et al.,1997).

If the flows from the creeks are sufficient, theswamps form small lakes. This usually occurs inlate winter. The capacity of each swamp isestimated to be 425 ML for Poochers Swamp and3500 ML for Mundulla Swamp (DENR, 1997).

Water from the swamps then recharges theunconfined aquifer via a series of runaway (sink)holes. These are preferred flow paths that allow the

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surface water to directly recharge the aquifer. Theannual input via these recharge holes is calculatedto be less than 10% of the total recharge (Herczeg,et al., 1997). Diffuse recharge is therefore thedominant recharge mechanism in the Tatiara PWA.

LOCAL HYDROSTRATIGRAPHY

Unconfined Aquifer

Groundwater flow in both the unconfined andconfined aquifers in the Tatiara PWA is generallyfrom east to west. The unconfined aquifer is amulti-lithological system which is hydraulicallycontinuous across the PWA. In the east, in theuplifted Pinnaroo Block, groundwater flowsthrough the Murray Group Limestone Formation.The limestone is absent west of the fault.Groundwater flow thereafter passes through thedune ridge consisting of the Bridgewater Formationbefore continuing through the Padthaway andBridgewater Formations beneath the coastal plain.

The thickness of the unconfined aquifer variesconsiderably throughout the region but generally itthins from east to west. For example in the centralportion of the PWA the aquifer is more than 80metres thick in the east (Hundred of Senior) butthins westward to be less than 40 metres thick onthe western boundary of the Hundred of Stirling.Aquifer thinning is more rapid in the south west ofthe PWA as the sediments near outcrops of granitebasement. Depth to water on the interdunal flat isgenerally less than five metres. In the east the depthto water can be in excess of 60 metres reflecting theincreased topography. A schematic east-west crosssection through the Tatiara PWA highlighting themain geological units is shown in Figure 5.

Coastal Plain

The unconfined aquifer beneath the coastal plainflows through the Padthaway, Bridgewater andCoomandook Formations. The aquifer is exploitedextensively for irrigation in the Hundreds ofStirling, Willalooka, Wirrega and Pendleton.

The uppermost geological unit is the PadthawayFormation which occurs only beneath theinterdunal flat. The maximum recorded thicknessis approximately 20 metres in the Hundred ofStirling. It consists mainly of an off-white, well-cemented, non-fossiliferous, fine-grained lime-stone. A well developed secondary porosity hasresulted in a highly transmissive aquifer.

Underlying the Padthaway Formation is theBridgewater Formation. Lithology in theBridgewater Formation does vary over the PWAbut generally it consists of fine to coarse shellyquartz sandstone. High well yields (up to300 L/sec. (Stadter and Love, 1987)) in thePadthaway and Bridgewater Formations haveenabled irrigators to adopt flood irrigation practisesparticularly in the Hundred of Stirling. The deepestof the geological units, the CoomandookFormation, is not used as an aquifer in the TatiaraPWA because it has a higher marl (calcareous clay)component than the overlying formations which hasresulted in lower well yields.

Eastern Highlands

In the eastern highlands area, the main geologicalunit of the unconfined aquifer is the Murray GroupLimestone Formation. The Murray GroupLimestone generally consists of a bryozoal andshelly limestone. Groundwater from the aquifer isprimarily used for irrigation but it is also used forthe town water supply of Bordertown. Well yieldsrange from 50 to 200 L/sec. The aquifer can besemi-confined depending on its saturated thicknessand the presence of an overlying clay referred to asthe Upper Tertiary Aquitard. The north-easternportion of Zone 9A in the Tatiara PWA isconsidered confined (Stadter et al., 1995).

The Murray Group Limestone Formation pinchesout before it reaches the coastal plain and isreplaced by the Bridgewater Formation in the formof a remnant dune ridge.

Confined Aquifer

In the Murray Basin, the unconfined and confinedaquifers are separated by a low permeabilityaquitard comprising the Ettrick Formation and theBuccleuch Beds. The Ettrick Formation consists ofglauconitic marl while the Buccleuch Beds aremainly carbonaceous clays. The combinedthickness of the aquitard is generally more than 20metres.

Vertical recharge to the confined aquifer from theoverlying unconfined aquifer in the PWA isconsidered to be very low. Recharge to the aquiferis predominantly via lateral throughflow from theeast, possibly sourced from the Dundas Plateau.

The confined aquifer in the Tatiara PWA is referredto as the Renmark Group. It has a similar wedgeshape as the unconfined aquifer in that it thins

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appreciably from the east to the west. Depth to theRenmark Group is more than 100 metres in theTatiara PWA.

Generally the confined aquifer consists of a seriesof thin interbedded limestone and sand aquifersseparated by thin carbonaceous clay units. Itdiffers from its counterpart in the Otway Basin (theDilwyn Formation) in that the top lithological unitscan consist of a fossiliferous sandstone orlimestone.

The sand units of the aquifer can be fine grained,and therefore difficult to screen. Well yields arerelatively low compared to the unconfined aquifer(10–20 L/sec.). There have been a relatively lownumber of wells drilled into the confined aquifer inthe Tatiara PWA. There is only one knownoperational confined aquifer well in the PWA.

GROUNDWATER MANAGEMENTAPPROACH

HISTORY

In 1984 the Tatiara area was proclaimed under theSouth Australian Water Resources Act 1976. Thiswas considered necessary because of concerns fromthe community that the rapid expansion ofirrigation activity in parts of the area was having adetrimental impact on the water resource. This waslater confirmed by Stadter (1984), who showed thatthere was a long-term decrease in groundwaterquality in the western part of the region.

At the time of proclamation, water licences wereissued on established irrigation activity and onproposed development. There was therefore noinitial assessment of PAVs for the area.

In 1986, the Tatiara Proclaimed Area was expandedto the east to include the Border Zone area. Asubsequent study (Stadter and Love, 1987) showedthe rate of extraction was near or exceedingrecharge in some areas. As part of the assessmentvertical recharge (ie. PAVs) were determined foreach Hundred.

In 1988, a management plan for the TatiaraProclaimed Wells Region was adopted and the areawas divided in to a number of sub-areas. At thistime the allocation in the Hundred of Willalookawas increased from 7900 ML/yr to approximately10 000 ML/yr. There was also an increase in the

North Pendleton sub-area from 2092 ML/yr to7000 ML/yr.

Allocations were voluntarily reduced at thebeginning of the 1997/1998 irrigation season by35% in the Hundred of Stirling. A 35% reductionin the groundwater allocation would bring it in linewith the estimated vertical recharge to the Hundred.At the same time changes were introduced to thecrop area ratios for ‘starter or finisher’ lucerne,spring lucerne, spring and autumn lucerne, lucerneseed, lucerne spring fodder and seed and lucerne“full”. The current irrigation equivalents andamended crop area ratios (after Desmier andSchrale, 1988) are attached in Appendix A.

In 1997, the allocation volume in that part of Zone9A in the Tatiara PWA was increased from2450 ML/yr to 4840 ML/yr following areassessment of the aquifer parameters for the zone.

MANAGEMENT ZONES

Unconfined Aquifer

The Tatiara PWA is divided into eight sub-areas asshown on Figure 4. They are:

! Sub-area 2 – includes the Hundred of Wirrega,the southern part of the Hundred of Pendleton,the south-western corner of the Hundred ofCannawigara and the western edge of theHundred of Tatiara.

! Sub-area 3 – is the Hundred of Willalooka.! Sub-area 5 – is the Hundred of Cannawigara.! Sub-area 6 – is the northern part of the

Hundred of Pendleton.! Sub-area 7 – is the Hundred of Stirling.! Part Zone 7A – in the northern part of Border

Zone 7A located in the Tatiara PWA andincludes most of the Hundred of Tatiara.

! Zone 8A – is Border Zone 8A. It includes theHundred of Senior, the southern part of theHundred of Shaugh, the eastern portion of theHundred of Cannawigara and a small part ofthe Hundred of McCallum.

! Part Zone 9A – is that part of Border Zone 9Alocated within the Tatiara PWA. It includes theHundred of Shaugh and a small slice of theeastern part of the Hundred of McCallum.

Confined Aquifer

Boundaries are yet to be established for theconfined aquifer in the South East region however

12

proposed boundaries have been recommended. Inthe Border strip zone boundaries have beenmaintained, hence Zone 8A, and parts of Zones 7Aand 9A are included in the Tatiara PWA along withthe management areas of Wirrega and Keith west ofthe Border area (Fig. 13).

THE MONITORING NETWORK

UNCONFINED AQUIFER

Current Monitoring Network

The Department for Water Resources and itspredecessors have been monitoring groundwaterlevels in the Tatiara PWA since 1975. Salinitymonitoring began in 1978.

Water Level Monitoring Network

The water level monitoring network in the TatiaraPWA has been in operation for more than 25 years.Over this period, the network has been upgradedand expanded to match the agriculturaldevelopment in the PWA. There are currently 69wells monitored for water level. These wells aremeasured quarterly (March, June, September andDecember) by the Department for Water Resources.

The locations of the current water level monitoringwells are shown on Figure 6. The number of waterlevel monitoring wells in the network is adequatefor the Tatiara PWA. The majority of wells areunderstandably concentrated in the area of highestrisk, namely the intensely irrigated area of theHundred of Stirling. There are only twoobservation wells in the Hundred of Shaugh but thisreflects the low level of irrigation activity in thissub-area.

Salinity Monitoring Network

There are currently a total of 149 observation wellsbroken up into two salinity monitoring networks inthe Tatiara PWA. The Tatiara Monitoring Networkis the main network in the PWA. There arecurrently 37 wells in this network. Sampling isundertaken by the Department for Water Resourcesand the sampling frequency is the same as for thewater level monitoring network.

The majority of salinity observation wells are in theTatiara Irrigation Network. These are privatelyowned wells that are sampled on an irregular basis.

A number of wells are also sampled regularly forfull major ion chemistry.

The location of wells in the salinity monitoringnetwork are shown on Figure 7. The distribution ofthe wells in the salinity monitoring network issimilar to the water level monitoring network inthat most are located in Sub-area 7, the Hundred ofStirling.

CONFINED AQUIFER

Water Level Monitoring Network

There are three water level observation wells in theconfined aquifer in the Tatiara PWA. They arelocated in the Hundreds of Shaugh, Tatiara andWirrega.

Salinity Monitoring Network

The two water level monitoring wells in theHundreds of Shaugh and Wirrega have also beenused to monitor groundwater salinity in theconfined aquifer.

CURRENT STATUS OF THEWATER RESOURCES

UNCONFINED AQUIFER

Groundwater Flow

The water table elevation zones for the unconfinedaquifer are shown on Figure 8. The direction ofgroundwater flow is generally from the SouthAustralian – Victorian Border in the east towardsthe coast in the west. The changes in hydraulicgradient as reflected in the spacing of the zones areinferred to represent changes in hydraulicconductivity in the aquifer. The gradient becomessteeper near the eastern boundary of the Hundredsof Stirling and Willalooka. This is the transitionfrom the Murray Group Formation to theBridgewater Formation. It therefore couldrepresent lower permeability in the BridgewaterFormation or it could be related to the KanawinkaFault. The gradient flattens to the west of the PWAand reflects high permeability in the Padthaway andBridgewater Formations beneath the coastal plain.

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Water Level Trends

Long term water level trends from hydrographslocated in the Tatiara PWA are shown on Figure 9.Only wells with more than five years data wereincluded in the assessment. In the intenselyirrigated part of the Hundred of Stirling, long-termwater level trends from bore hydrographs show ageneral decline in the water table of up to 14 cm/yr.The decline in water level would suggest thecurrent level of extraction in the Hundred ofStirling is too high and therefore not sustainable inthe long-term. Representative hydrographs fromeach of the sub-areas are included in Appendix B.

There is also an observed long-term decline in thewater table of approximately 2.5 cm/yr in an areasouth-west of Bordertown. At this stage the reasonfor the decline has not been investigated.

In the southern portion of the PWA water levels inthe unconfined aquifer are rising in excess of5 cm/yr. The rise in the water table is considered tohave been caused by increased vertical rechargeresulting from the clearance of native vegetation byearly European settlers.

At the present time this is not considered a majorissue as the depth to water is more than 15 metresin this area and the average annual increase is only5 cm. The area should however be monitored forany further significant changes.

Salinity Distribution

The salinity distribution for the Tatiara PWA isshown on Figure 10. Generally, the salinity rangesfrom approximately 1000 mg/L in the east to morethan 7000 mg/L in the west. The most obviousfeature from the figure is the groundwater salinityvalues in the Hundred of Stirling which are inexcess of 7000 mg/L.

Unfortunately there are no salinity monitoring wellslocated in the southern part of the PWA where thewater table is rising. Given that the rise in thewater table is probably a result of land clearancethen it would be expected that groundwater salinityis also increasing in this area.

Salinity Trends

The most notable increase in groundwater salinityis occurring in Sub-area 7, the Hundred of Stirling.Groundwater sampled from a number of wells in

this area show salinity increasing at a rate of morethan 100 mg/L annually. There are a number offactors that contribute to this increase, the maincauses are considered to be:

! in the Hundred of Stirling extraction exceedsvertical recharge. Evidence for this is thesubstantial increase in groundwater salinity inthe last 25 years and a long term decline in thewater table. The decline in the water tableindicates that a proportion of throughflow isalso used. Groundwater is not moving fastenough to remove salts from the area. This iscompounded by a high concentration ofirrigation activity in the area. This ultimatelyresults in an increase in the groundwatersalinity caused by continuous recycling of thegroundwater. Water use figures are based onlyon the crop water requirement and do notinclude irrigation losses. Flood irrigationmethods are probably extracting many timesthe crop water use figure.

! lucerne, the major crop grown in the Hundredof Stirling, is a high water use crop. As wateris drawn up through the root system salt nottaken up by the plant accumulates in the rootzone. The relatively high water use of lucerneresults in a substantial salt load remaining inthe soil profile. When irrigation water of ahigher salinity is applied to the plant it mustdraw up more water to survive. This in turnleaves a higher salt load in the soil profile. It isthis process that eventually reduces the cropyield of the plant. The salt that hasaccumulated in the soil profile then percolatesback down into the aquifer during subsequentirrigation applications or from rainfall recharge.There is therefore a continuous cycle increasingthe groundwater salinity.

Studies have shown that in the Hundred of Stirlinglucerne seed and dry matter crop yields decreasewhen the salinity of irrigation water exceeds7000 mg/L (DENR, 1997). As the salinity in someparts of the sub-area already exceed 7000 mg/L, inthe short term corresponding reductions in cropyields should be expected. In the long-term thereare very few crops that can be grown economicallywith a groundwater salinity in excess of 7000 mg/LTDS. The alternatives therefore given the currentrate of salinity increase are limited.

14

CONFINED AQUIFER

Water Level Trends

There are three confined aquifer water levelmonitoring wells in the Tatiara PWA. Hydrographsof the wells are presented in Appendix B. Thehydrograph from the observation well in theHundred of Shaugh (SHG006) shows a long termincrease in the potentiometric surface ofapproximately 2.5 cm/yr. The increase in thepotentiometric surface is probably related to anincrease in overburden pressure resulting from arise in the water table in the unconfined aquiferrather than an increase in vertical recharge. Thechange in overburden pressure would also explainthe decline in the potentiometric head in theconfined aquifer as observed in the hydrographlocated in the Hundred of Wirrega. The well(WRG025) is located in the mid-western portion ofthe Hundred. In this area the water level in theunconfined aquifer is declining.

There is only one well utilising groundwater fromthe confined aquifer but it has only beenoperational for the past year and therefore can notyet have had an impact on groundwater levels.

Observation well TAT027 located in the Hundredof Tatiara shows no long-term change ingroundwater level.

Salinity Distribution

The two wells sampled for groundwater salinityWRG025 and TAT027 are programmed to besampled every three years as part of the BorderZone observation network. Observation wellWRG025 was sampled only in 1993. The salinityof the sample was measured at 1227 mg/L TDS.Observation well TAT027 has been sampled twice,in 1993 and 1996. Salinity was measured at1233 mg/L and 1250 mg/L respectively.

WATER DEMAND

UNCONFINED AQUIFER

Historical Demand

The historical and current estimated crop water use,and allocation, for each sub-area as supplied by theDepartment for Water Resources – Policy Division

are shown on Tables 1 and 2 respectively. The datais broken down into irrigation use and combinedindustrial and recreational use.

The allocation volumes vary slightly from season toseason. The changes are due to changes in croparea ratios and increases in individual waterlicences following successful legal appeals(L. Schmidt, pers. com.). In 1997 in Sub-area 7(Hundred of Stirling) the annual allocation wasvoluntarily reduced from 31 250 ML to 20 310 ML.This is a net reduction in total allocation of 35%and was implemented at the request of the localcommunity. Crop area ratios for lucerne were alsochanged as part of the 35% reduction. The newcrop area ratios for lucerne seed are presented inAppendix A.

The water use figures in Table 2 for Sub-area 7, theHundred of Stirling (1997/98 and 1998/99) havenot been corrected to the new crop area ratiosystem. DWR are in the process of altering thedatabase to accommodate for the new CARs. Theytherefore do not reflect the decline in water useassociated with the increase in crop area ratio.Water use should be approximately 17-18,000 MLfor Sub-area 7. Figures calculated on the new croparea ratio system are not available.

Theoretically under the old CAR system anirrigator with a 100 Ha IE licence could irrigate 120Ha of lucerne seed (ie. a CAR of 1.2 for lucerneseed). Under the new system the 100 ha IE hasbeen reduced by 35%. Therefore a 100 ha IElicence would be decreased from 100 ha IE to 65Ha IE. The new ratio for a 13 week irrigationperiod between November and March is 1.9. Theirrigator can therefore irrigate an area of 123.5 haof lucerne seed.

In 1998/99 irrigation season 50 out of the 60irrigators that planted lucerne seed used the 1.9Crop Area Ratio.

The water usage volume is estimated from seasonalreturns supplied by the water licensees. Theestimation of the volume relies on the veracity ofthe water user and the irrigated crop waterrequirement method. In both instances, therefore,the figures should be considered only as anapproximation. The volume extracted from theaquifer, especially using flood irrigation methods,will be significantly higher than the irrigated cropwater use value.

Table 1 Tatiara PWA annual groundwater allocations

Sub-areas Irrigation Season (in ML)83/84 84/85 85/86 86/87 87/88 88/89 89/90 90/91 91/92 92/93 93/94 94/95 95/96 96/97 97/98 98/99

Part Zone 7AIrrigation 6070 6070 6070 6070 6136 6136 6206 6446 6455 6455 6455 6550 6550 6564 6699 6564Industrial and Recreational 320 320 320 320 320 320 320 320 320 320 503 510 510 510 510 510Sub-area Total 6390 6390 6390 6390 6457 6457 6526 6766 6776 6776 6959 7060 7060 7075 7209 7075Zone 8AIrrigation 1659 1659 1659 1659 2228 2228 3496 3597 3722 2454 3722 3820 2552 2639 4039 5041Industrial and Recreational - - - - - - - - - - - 16 16 16 16 16Sub-area Total 1659 1659 1659 1659 2228 2228 3496 3597 3722 2454 3722 3836 2568 2654 4055 5056Part Zone 9AIrrigation 1686 1686 1686 1686 1686 1686 1686 1686 1686 1686 1686 1686 1686 1686 3330 3330Industrial and Recreational - - - - - - - - - - - - - - - -Sub-area Total 1686 1686 1686 1686 1686 1686 1686 1686 1686 1686 1686 1686 1686 1686 3330 3330Sub-area 2Irrigation 28994 28994 28994 28994 29225 29494 29494 29519 29519 29519 30717 30618 30618 30882 31606 31519Industrial and Recreational - - - - - - - - - - 119 394 394 130 115 101Sub-area Total 28994 28994 28994 28994 29225 29494 29494 29519 29519 29519 30836 31011 31011 31012 31721 31620Sub-area 3Irrigation 10225 10225 10225 10225 10352 10352 10352 10352 10352 10352 10583 10583 10583 10583 10583 10583Industrial and Recreational - - - - - - - - - - - - - - - -Sub-area Total 10225 10225 10225 10225 10352 10352 10352 10352 10352 10352 10583 10583 10583 10583 10583 10583Sub-area 5Irrigation 2951 3341 3341 3386 3386 3386 3616 3616 3847 3847 3886 4057 4098 4097 4097 4098Industrial and Recreational - - - - - - - - - - 29 29 29 29 29 29Sub-area Total 2951 3341 3341 3386 3386 3386 3616 3616 3847 3847 3916 4086 4127 4126 4126 4127Sub-area 6Irrigation 5341 5341 5341 5341 5870 5870 5986 7147 7147 7147 7147 6621 6621 6621 6646 6646Industrial and Recreational - - - - - - - - - - - - - - - -Sub-area Total 5341 5341 5341 5341 5870 5870 5986 7147 7147 7147 7147 6621 6621 6621 6646 6646Sub-area 7Irrigation 30528 30528 30528 30528 31060 31223 31511 31511 31519 31519 31711 32554 31931 31932 23535 20733Industrial and Recreational 165 165 165 165 165 165 165 165 165 165 171 178 178 178 178 181Sub-area Total 30693 30693 30693 30693 31224 31388 31676 31676 31684 31684 31882 32732 32109 32110 23713 20914Annual Total 87940 88330 88330 88375 90427 90860 92832 94359 94733 93465 96731 97615 95765 95866 91384 89351

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Table 2 Tatiara PWA annual groundwater usage

Sub-areas Irrigation Season (in ML)83/84 84/85 85/86 86/87 87/88 88/89 89/90 90/91 91/92 92/93 93/94 94/95 95/96 96/97 97/98 98/99

Part Zone 7AIrrigation 4477 2820 3458 3631 4243 3728 3022 2755 2170 2500 2386 2788 2601 2193 2908 2679Industrial and Recreational 320 320 320 320 320 304 320 320 127 0 0 0 0 0 0 0Sub-area Total 4797 3140 3778 3951 4564 4031 3343 3076 2297 2500 2386 2788 2601 2193 2908 2679Zone 8AIrrigation 0 0 140 86 356 603 627 665 496 323 420 470 493 454 373 795Industrial and Recreational - - - - - - - - - - - 0 0 0 0 0Sub-area Total 0 0 140 86 356 603 627 665 496 323 420 470 493 454 373 795Part Zone 9AIrrigation 0 0 1098 446 446 441 441 441 441 441 441 441 441 441 937 1646Industrial and Recreational - - - - - - - - - - - - - - - -Sub-area Total 0 0 1098 446 446 441 441 441 441 441 441 441 441 441 937 1646Sub-area 2Irrigation 19384 20299 21657 21047 20813 19969 20113 19806 21013 20029 18440 19773 19062 16927 19322 19991Industrial and Recreational - - - - - - - - - - 0 0 0 0 0 0Sub-area Total 19384 20299 21657 21047 20813 19969 20113 19806 21013 20029 18440 19773 19062 16927 19322 19991Sub-area 3Irrigation 5296 5168 5561 5386 6138 5962 6561 6709 6701 5785 6145 7554 7308 6292 6092 6049Industrial and Recreational - - - - - - - - - - - - - - - -Sub-area Total 5296 5168 5561 5386 6138 5962 6561 6709 6701 5785 6145 7554 7308 6292 6092 6049Sub-area 5Irrigation 0 350 1829 1432 1556 1711 1323 1359 1175 1178 1225 1078 1041 1500 1500 1968Industrial and Recreational - - - - - - - - - - 0 0 0 0 0 0Sub-area Total 0 350 1829 1432 1556 1711 1323 1359 1175 1178 1225 1078 1041 1500 1500 1968Sub-area 6Irrigation 1154 733 753 1058 1209 1469 1993 1951 2883 3100 3328 4194 4462 4044 4803 4648Industrial and Recreational - - - - - - - - - - - - - - - -Sub-area Total 1154 733 753 1058 1209 1469 1993 1951 2883 3100 3328 4194 4462 4044 4803 4648Sub-area 7Irrigation 23622 23236 24828 24038 24647 24259 23856 22133 26745 26120 24298 27372 24380 24454 24674 25667Industrial and Recreational 152 152 152 152 152 157 165 164 165 152 152 152 144 0 0 0Sub-area Total 23774 23388 24980 24190 24799 24416 24021 22297 26909 26272 24450 27524 24524 24454 24673* 25667*Annual Total 54406 53078 59795 57596 59881 58601 58421 56304 61915 59628 56835 63821 59932 56305 60609 63442

* includes old CAR for lucerne seed of 1.2

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Table 3 Tatiara PWA current PAVs, vertical recharge, allocation and usage (all in ML)

Sub-area PAV Vertical Recharge Allocation(1998/99)

Use(1998/99)

% of UsedAllocation

AvailableAllocation

Part Zone 7A 7500 6000 7075 2679 38% Closed

Zone 8A 7700 7720 5056 795 16% Available

Part Zone 9A 4840 4840 3330 1646 49% Available

Sub-area 2 28 120 126 500 31 620 19 991 63% Closed

Sub-area 3 10 000 15 040 10 583 6049 57% Closed

Sub-area 5 4200 4200 4127 1968 48% Closed

Sub-area 6 7400 7440 6646 4648 70% Closed

Sub-area 7 20 310 19 260 20 914 225 667 123% Closed

Total 90 070 91 000 89 351 63 443 71%

1. includes point source recharge component.

2. includes old CAR for lucerne seed of 1.2

Table 4 Stock Use Tatiara PWA 1996/97

Approximate Stock NumbersSub-area Estimate StockWater Use ML Sheep Dairy Cattle Meat Cattle Pigs

Part Zone 7A 250 66 520 625 3050 3880

Zone 8A 280 78 100 5 4870 270

Part Zone 9A 170 33 850 — 5145 —

Sub-area 2 590 162 420 1120 8670 2130

Sub-area 3 340 68 350 — 10 060 —

Sub-area 5 215 46 260 15 240 140

Sub-area 6 170 35 000 40 4330 305

Sub-area 7 285 70 000 — 6500 225

Total 2300 560 500 1805 45 025 6950

Current Demand

The total annual groundwater allocation for the1998/1999 irrigation season for the Tatiara PWAwas 89351 ML. Total groundwater usage for thePWA is estimated to be 63442 ML whichrepresents approximately 71% of the totalallocation. Table 3 is a break down of the PAVs,estimated rainfall recharge, 1998/99 allocationand water use figures on a sub-area basis.Vertical recharge figures are from Stadter andLove (1987) and Stadter et al., (1995).

In Sub-area 2, 2300 ML are included in thevertical recharge calculation as a contributionfrom preferred flow path recharge (ie. runawayholes).

Estimated stock water use and the correspondingapproximate stock numbers for the 1996/97season are shown in Table 4. The data wereobtained from the Australian Bureau of StatisticsHobart. Daily stock consumption figures werebased on data from the NSW Department ofAgriculture and are given in Appendix C. Thestock use estimates are to the nearest 5 ML. Totalannual stock use for the PWA is estimated to be2300 ML.

There are no data on domestic groundwater usebut the extensive use of rainwater tanks wouldsuggest this component would be a small fractionof the overall water budget.

There are five town water supply wells locatedwest of Bordertown. Combined water use fromthe wells between 1991/1992 and 1998/1999ranged from 545 to 621 ML/yr. The use for1998/1999 was 621 ML, which is approximately0.5% of the total allocation for the PWA. Keithtownship receives its water from the MurrayRiver. Total water usage for Keith township was347 ML during the 1998/1999 season.

In Sub-area Part Zone 7A the PAV is7500 ML/yr. This is the total allocation for thewhole of Zone 7A. The PAV should be~6000 ML, but this figure will have to be verifiedby hydrogeological assessment.

In Sub-area 3, the Hundred of Willalooka, thePAV was set at 10000 ML/yr even though therainfall recharge rate was calculated to be15040 ML. It was not increased because therewas evidence that suggested salinity stratificationis occurring in the unconfined aquifer in this area(Stadter and Love, 1987). Here poor quality

18

groundwater at the top of the aquifer(>8000 mg/L) is separated from better qualitywater at depth by a marl in the PadthawayFormation. Increased groundwater extractionwould exacerbate downward leakage of this moresaline water hence following discussion with thecommunity it was agreed to adopt a lower figureas a conservative approach.

Future Demand

In two sub-areas (Zone 8A and Part Zone 9A)allocations have not reached the PAV limit. OnlyZone 8A has been included in the pro-rata roll outhowever because there were sufficientapplications at the time of determination to takeallocation up to the PAV threshold in part Zone9A. Existing allocations, stock and domestic use,expected plantation expansion and theenvironment were considered as part of the pro-rata rollout assessment for Zone 8A (Table 5).

Most of Zone 8A is used only for sheep grazing.There is some evidence to suggest water use isincreasing in the area but it is still only around16% of the allocation.

The remaining sub-areas all have significantpercentages of allocation unused (Table 3). Thisis particularly concerning in Sub-area 3, theHundred of Willalooka. Declining water levelsand increasing groundwater salinity wouldsuggest current levels of extraction are notsustainable.

Whilst stock numbers will change with seasonsand market conditions such changes will haveonly a small effect on the relative magnitude ofgroundwater use.

SA Water believe that Bordertown's water use hasstabilised and forecast a maximum annual usageover the next five years at 700 ML.

CONFINED AQUIFER

Historical Demand

The confined aquifer has not been previouslyutilised in this PWA.

Current Demand

There is only one known well that extracts waterfrom the confined aquifer. Unfortunately water

allocation and water use figures are not availablefor the confined aquifer.

Future Demand

The proposed PAVs for the confined aquifer forboth South Australia and Victoria are presented inTable 6. The management zones are shown onFigure 13.

As the depth to the confined aquifer is aneconomically an expensive exercise whencompared to the relatively shallow depths of theunconfined aquifer there is little likelihood thatthere will be any future demand for the aquifer.Wells in this area are known to produce fine sandtherefore it is unlikely that the confined aquiferwill be actively targetted in the immediate future.

WATER BALANCE

UNCONFINED AQUIFER

A water balance has been determined for eachsub-area in the Tatiara PWA. The figures arebased on a water balance undertaken by Stadterand Love (1987). The main differences from theearlier budget are that changes in storage and theadjustments to sub-areas as a result of theinclusion of the Border Zones have been takeninto account (Table 7). Lateral inflow andoutflow calculations were estimated using flow-net analysis.

Annual rainfall recharge to Sub-area Part Zone7A has been taken as 6000 ML/yr. The methodused to estimate rainfall recharge was to assessthe relationship between seasonal changes ingroundwater level (measured from hydrographs)and an assumed specific yield of 0.1. Each sub-area was classified into recharge zones accordingto soil type, morphology and hydrogeologicalcondition. These recharge zones were furthersubdivided to reflect depth characteristics of soiltypes, depth to water and vegetation cover.

Groundwater use figures are for the 1998/1999irrigation season (these are not the total allocationfigures). Where applicable they include the totalirrigation use, industrial and recreational use foreach sub-area.

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Table 5 Pro-Rata determination for Sub-areas in the Tatiara PWA

Zone Adopted1996 PAV

(ML)

ExistingAllocation

(ML)

StockUse(ML)

Dom.Use(ML)

TownUse(ML)

ForrestryCommitment

(ML)

EnvironmentalCommitment

(ML)1

Volume Availablefor Pro-Rata

Allocation (ML)

Zone 8A 7700 6120 198 92 0 0 0 1290

1. No part of the adopted PAV has been taken for environmental requirements

Table 6 Proposed PAVs for the TCSA in South Australia and Victoria

South AustralianManagement Areas

Proposed PAV(ML/yr)

VictorianManagement Areas

Proposed PAV(ML/yr)

1A 9 200 1B 14 400

2A 2 900 2B 5 100

3A 1 900 3B 1 100

4A 690 4B 300

5A 550 5B 550

6A 350 6B 350

7A 350 7B 350

8A 340 8B 340

9A 570 9B 630

10A 320 10B 560

11A 0 11B 0

Copeville 940 Dartmoor 18 600

Karoonda 1 500 Goroke 2 200

Keith 2 500 Kaniva 1 000

Kingston 24 972 Little Desert 1 100

Lameroo 1 200 Nhill 1 200

Millicent 12 000

Mindarie 780

Monbulla 4 300

Naracoorte 3 900

Wirrega 960

1. For the proposed PAVs where the volume is less than 1000 ML, the PAV has been rounded upwards to the nearest 10 ML.

2. For the proposed PAVs where the volume is greater than 1000 ML, the PAV has been rounded upwards to the nearest 100 ML.

3. The northern parts of Zones 11A and 11B contain saline groundwater with a salinity greater than 3000 mg/L. The determined volumes for theareas where the TDS is less than 3000 mg/L are insignificant (less than 100 ML).

Table 7 Water Balance for Tatiara PWA

Sub-area

Inputs Pt Zone7A

Zone8A

Pt Zone9A

Sub-Area2

Sub-Area3

Sub-Area5

Sub-Area6

Sub-Area7

Totals

Groundwater Inflow 8830 3650 3560 11 980 28 040 14 590 12130 25 040

Rainfall Recharge 6000 7720 4840 26 500 15 040 4200 7440 19 260

Total In 198 820

Outputs Pt Zone7A

Zone8A

Pt Zone9A

Sub-Area2

Sub-Area3

Sub-Area5

Sub-Area6

Sub-Area7

Totals

GroundwaterOutflow

9830 16 545 14 610 31 680 36 525 9590 5190 7440

Groundwater Use(1998/99)

2680 795 1645 19 990 6050 1970 4650 18 0001

Total Out 186 190

1. Estimation based on changes to CAR system.

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The water budget would suggest that the TatiaraPWA is approximately in balance (Table 7).However it does not take into account the ~1 mreduction in water levels in the north-west portionof the PWA. If it were included, the water budgetwould not balance. There are a number ofpossible explanations for this discrepancy but it isprobably a result of the previously highlightedunderestimation in groundwater usage.

The decline in groundwater levels in Sub-area 7would suggest that groundwater extraction isexceeding vertical recharge. The affect this ishaving on the groundwater resource, particularlythe deterioration in groundwater quality in thesub-area, is well documented. Its potential effectsdown-gradient of the densely irrigated areas arealso noted.

CONFINED AQUIFER

As previously discussed the proposed PAVs forthe management zones for the confined aquiferare presented in Table 6.

POTENTIAL IMPACTS THE USEOR TAKING OF WATER FROMONE RESOURCE MAY HAVE ONANOTHER RESOURCE

The potential detrimental impacts taking, orusing, water from one resource may have on thequantity or quality of water of another resource inthe Tatiara PWA were considered in thefollowing situations:

• the impact of using surface water toartificially replenish the groundwater system.

• the impact taking groundwater from theunconfined aquifer may have on the confinedaquifer.

• the impact taking groundwater from theconfined aquifer may have on the unconfinedaquifer.

In all three scenarios consideration was also givento the impacts extraction may have acrossmanagement boundaries.

THE IMPACT OF USINGSURFACE WATER TOARTIFICIALLY REPLENISH THEGROUNDWATER SYSTEM

The unconfined aquifer receives most of itsrecharge via diffuse percolation of rainfallthrough the soil profile and unsaturated zone.However, during high rainfall events surfacewater in the form of run-off also enters the aquiferdirectly. In the Tatiara PWA, Poochers Swampand Mundulla Swamp are the two main areas thatnaturally recharge the unconfined aquifer. Thereare also a number of smaller sites that alsorecharge the aquifer. Some of these occurnaturally such as sinkholes whilst others are man-made drainage wells. The main purpose of theman-made wells is to relieve surface flooding.Distinguishing between what is naturallyoccurring and man-made can be somewhatarbitrary.

Herczeg et al., (1997) undertook a study of pointsource recharge at a number of sites in the SouthEast region. One of the selected sites wasPoochers Swamp. Results from their studyshowed that recharge to the unconfined aquiferwas only detectable on a local scale (less than500 m) and that groundwater mounds arising frompoint source recharge dissipate within 2–4 monthsafter the cessation of rainfall. They also showedthat even though the salinity of the surface waterentering into the aquifer is very low, it does nothowever affect the regional groundwater salinity.

As the effects of point source recharge to theunconfined aquifer are localised it is unlikely thatthere would be any impacts across watermanagement boundaries.

There is the potential to contaminate the aquiferwith nutrients including those ions or organiccompounds containing nitrogen (NO2

-, NO3-,

NH4+) and phosphorus. These can come from

fertilisers or sewage that may be collected by run-off and flows directly into the aquifer. This typeof contamination can also occur through diffuserecharge processes so it would be difficult topinpoint an individual source.

It is concluded therefore that the addition ofsurface water to artificially replenish thegroundwater system would have only minimaleffects on groundwater levels and salinity in theunconfined aquifer.

21

THE IMPACT TAKING OR USINGGROUNDWATER FROM THEUNCONFINED AQUIFER MAYHAVE ON THE CONFINEDAQUIFER AND ADJACENT PWAs

The aquitard which separates the unconfined andconfined aquifers in the Tatiara PWA is generallymore than 20 metres thick and has a very lowvertical permeability. While the potential forrecharge exists (ie. the head in the unconfined ishigher than the head in the confined aquifer) thelow permeability would inhibit downward leakageto the confined aquifer. It is therefore unlikelythat any use in the unconfined aquifer woulddirectly affect the confined aquifer.

There are only a few examples in the South Eastregion where the extraction from the unconfinedaquifer has impacted across managementboundaries. One such example may exist in theTatiara PWA. In Sub-area 7, the Hundred ofStirling, long-term water level decline of morethan 5 cm/yr have been occurring over a largeportion of the sub-area. However a similardecline is also being experienced in the northernportion of Sub-area 3, the Hundred of Willalookaand the north-western part of Sub-area 2, in theHundred of Wirrega. Whether this is due to anexpansion of a drawdown cone emanating fromthe Hundred of Stirling or whether the long-termdecline in the remaining Hundreds is a localphenomenon has not been ascertained.

In the long-term, a decline in groundwater qualityis expected down-gradient of the densely irrigatedarea in Sub-area 7. This would occur outside theTatiara PWA with the largest impact expected inthe eastern portion of the Hundred of Laffer andpossibly in the Tintinara-Coonalpyn moratoriumarea.

THE IMPACT TAKING OR USINGGROUNDWATER FROM THECONFINED AQUIFER MAY HAVEON THE UNCONFINED AQUIFER

For the same reasons as outlined above the lowpermeability aquitard would make it mostunlikely that extraction from the confined aquiferwould impact on the unconfined aquifer.

If groundwater were to be taken from the confinedaquifer then the only foreseeable way it could

effect the unconfined aquifer would be if thewater from the confined aquifer were added to theunconfined aquifer. In this scenario, there may bea volumetric effect, due to the increased quantityof water applied to the unconfined aquifer, andpossibly a quality effect due to the addition ofsalts. As the groundwater in the confined aquifergenerally has a lower salinity than the unconfinedaquifer, the addition of an extra salt load is aminor issue. The application of an additionalsupply of water is unlikely to have any long-termeffect on the unconfined aquifer in the TatiaraPWA, given the minimal response witnessedduring point source recharge from surfacerecharge events.

CONCLUSIONS

An unconfined aquifer water balance calculatedfor the Tatiara PWA would suggest that the areais approximately in balance if it were not for asignificant decline in water levels in the denselyirrigated western portion of the PWA.

Groundwater salinity monitoring since the mid-1970s indicates a significant increase ingroundwater salinity in Sub-area 7, the Hundredof Stirling. Groundwater recycling due to overuseis believed to be the main cause of the salinityincrease in this area. In the eastern highlands thewater table is rising slightly, as is the groundwatersalinity. Increased recharge following landclearance is considered to be responsible for thesetrends.

In Sub-area 7, the Hundred of Stirling the PAVwas voluntarily cut by 35% at the beginning ofthe 1997/98 irrigation season. At this time thecrop area ratio was changed for lucerne seed tocompensate for the reduction.

Generally the water level and salinity monitoringnetworks are adequate for the Tatiara PWA.

The potential impacts of using one water resourcewould have on another were considered onlyminor in the Tatiara PWA. However there arepotential down-gradient impacts from the denselyirrigated area in the western portion of the PWA.

22

RECOMMENDATIONS

The following recommendations are made:

• obtain accurate water extraction figuresparticularly in relation to flood irrigationpractices.

• increase the unconfined aquifer salinitymonitoring network in the southern portion ofthe PWA,

• increase the unconfined aquifer water levelmonitoring network in Sub-area Part Zone9A,

• a study to assess potential salinity increases inthe eastern highlands area,

• if the confined aquifer is to be targetted forfuture use then the confined aquifer networkshould also be increased.

REFERENCES

Department of Environment and NaturalResources, 1997. Tatiara Prescribed WellsArea draft groundwater management plan.Adelaide, South Australia.

Desmier, R.E., and Schrale, G., 1988. Estimationof the water requirements of irrigated crops inTatiara Proclaimed Region. Department ofAgriculture South Australia. Report No. 127

Herczeg, A.L., Leaney, F.W.J, Stadter, F., Allan,G.L., Fifield, L.K., 1997. Chemical andisotopic indicators of point-source recharge toa karst aquifer, South Australia. Journal ofHydrology 192: 271–299.

Stadter, F., Bradley, J., DeSilva, J., Foley, G.,Robinson, M., 1995. Five year technicalreview 1991–1995 Border (GroundwaterAgreement) Act, 1985.

Stadter. F., Love, A., 1987. Tatiara ProclaimedRegion groundwater assessment. Departmentof Mines and Energy South Australia. ReportBook 87/87.

Stadter, M.H., 1984. Keith-Willalooka-Border-town irrigation area investigation. Progressreport No. 2. Department of Mines andEnergy South Australia. Report Book No.84/29.

23

Figures

#S

#S

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WIRREGA

LAFFER

JOYCE

FOX

GLYDE

TATIARAWELLS

SHAUGHCOOMBE

SENIOR

HYNAM

SPENCE

GREY

BRAY

MAKIN

ROSS

FIELD

BINNUM

COLES

STIRLING

PETHERICK

SANTO

JESSIE

PEACOCK

SHORT

RICHARDS

NEVILLE

BENARA

BEEAMMA

SMITH

MESSENT

GEEGEELA

ARCHIBALD

SYMON

YOUNG

MARCOLLAT

CONMURRA

MCNAMARA

MCCALLUM

PENDLETON

PENOLA

MINECROW

COLEBATCH

LANDSEER

JOANNA

DUFFIELD

WILLALOOKA

BLANCHE

RIDDOCH

BOWAKA

GAMBIER

COMAUM

GLEN ROY

LACEPEDE

MAYURRA

TOWNSEND

KENNION

PARSONS

CAROLINE

WATERHOUSE

CANNAWIGARA

LOCHABER

WOOLUMBOOL

MONBULLA

MINGBOOL

ROBERTSON

HINDMARSH

KILLANOOLA

MACDONNELL

NANGWARRY

NARACOORTE

RIVOLI BAY

KONGORONG

LAKE GEORGE

MURRABINNA

MOUNT BENSON

MOUNT MUIRHEAD

Robe

KEITH

PENOLA

Lucindale

Padthaway

Beachport

MILLICENT

BORDERTOWN

Kingston SE

NARACOORTE

MOUNTGAMBIER

ZONE 9A

ZONZONE 1A

ZONE 2A ZON

ZONE 3A

ZON

ZONE 4A ZON

ZONE 5A ZON

ZONE 6A ZON

ZONE 7A ZON

ZONE 8A ZON

#S#S

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Moomba

Ceduna

Tarcoola

ADELAIDE

Oodnadatta

Coober Pedy

Olympic Dam Leigh Creek

Port Augusta

Port Lincoln

Mount Gambier

Marla

AV : 200454_011.APR

SOUT

H A

USTR

ALIA

VICT

ORIA

Figure 1

Prescribed Wells AreasComaum-CarolineLacepede-KongorongNaracoortePadthawayTatiara

Management zoneBorder Designated Zones

10 0 10 20 Kilometers

38°38°

37°37°

36°36°

140°

140°

141°

141°

Hundred boundary

TATIARA PRESCRIBEDWELLS AREA

SOUTH EAST PRESCRIBED WELLS AREALOCATION PLAN - TATIARA PRESCRIBED WELLS AREA

South East South Australia

Figure 2 Geological provinces in the South East Region.

KILOMETRES

0 100

Portland

Nangwarry

Port Macdonnell

Naracoorte

Robe

Casterton

River

Bordertown

Keith

VIC

TO

RIA

Kingston

MountGambier

MURRAY

BASIN

OTWAY

BASIN

TARTWAUPFAULT

DUNDAS

PADTHAWAY

RIDGE

PLATEAU

KA

NA

WIN

KA

FAULT

200454-008

Gle

nel

g

S.A.N.S.W.

VIC.

Melbourne

OTWAY BASINKILOMETRES

0 200

Adelaide

Tatiara Prescribed

Wells Area

SO

UT

HA

UST

RA

LIA

MA

RM

ON

JA

BU

KFA

ULT

200454-009

STRATIGRAPHIC AND HYDROSTRATIGRAPHIC UNITS

OTWAY AND MURRAY BASINS

MURRAY BASINOTWAY BASINAGE

Padthaway Fm

Bridgewater Fm

Coomandook Fm

Limestone, sand clay

Lagoonal.

Lacustrine,

beach ridge.

Qtz sand, minor claystranded beach ridges.Inter-ridge fluvio-lacustrine depositsmarl. Restricted marineshelf.

Consists of Blanchetown Clay,

Shepparton Fm, Woorinen Sand

Loxton-Parilla sands are regional

unconfined aquifer. In much of

Murray Basin the Gambier

Limestone is confined.

Limestone aquifer is unconfined in

parts of SA. Elsewhere confined by

Bookpurnong Formation.

Major groundwater resource in

designated area.

Cretaceous aquifer system present

in Otway Basin, separated from

Murray Basin by Padthaway Ridge.

Forms basement highs ofPadthaway Ridge and DundasPlateau.

Grey-green

glauconitic marl.

Shallow marine-

lagoonal

Carbonaceous silts,

sands, clays, lignitic.

Fluvio-lacustrine

flood plain and swamp

environment.

Fossiliferous limestone.

Shallow marine

platform

Fossiliferous

limestone

Open marine platform

Interbedded

sequence of sand,

gravel, clay, fluvial

deltaic

Shales, lacustrine

volcanogenic sand,

clay fluvial

Marl

Sand

Claystone

Prodelta muds

Marl and dolomite

Glauconitic

fossiliferous marl

Metamorphicand igneous

Gambier

Limestone

Dilwyn Clay

Dilwyn Clay

Dilwyn Fm

(Undiff)

Dilwyn Sand

Belfast Mudstone

Pember Mudstone

Pretty

Hill Sandstone

Renmark

Clay

Renmark Group

undifferentiated

Duddo

Limestone

Tertiary

limestone

aquifer

Pliocenesandsaquifer

Tertiary

confined sand

aquifer

Cretaceous

aquifer/aquitard

system

Upper Tertiaryaquitard

Lower tertiaryaquitard

Olney Formation is time

equivalent of Dilwyn Formation.

Hydraulic

basement

Quaternary

aquitardAeolian

Bookpurnong

Formation

Ettrick Marl

Renmark Sand

Renmark Clay

Loxton-ParillaSand

Woorinen

Sand

Gellibrand Marl

Pebble Point FmTimboon

Sand

EumerallaFm

Narrawaturk

Marl

PLEISTOCENE

PLIOCENE

MIOCENE

EOCENE

LATESHERBROOK

GROUP

OTWAY

GROUP

KANMANTOO

GROUP

EARLY

PALAEOCENE

OLIGOCENE

Q

TE

RT

IAR

Y HE

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ES

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RY

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OU

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AY

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EN

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ND

A

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OU

P

WA

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ER

RIP

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OU

P

CR

ETA

CE

OU

S

ROCK UNIT ROCK UNITCOMMENTSENVIRONMENT

LITHOLOGY

HYDRO-

STRATIGRAPHIC

UNITENVIRONMENT

LITHOLOGY

C/O

MepungaFormation

Figure 3 Stratigraphic and hydrostratigraphic units of the Otway and Murray Basins.

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NGARKATCONSERVATION PARK

MOUNT SHAUGHCONSERVATION PARK

ABERDOURCONS PARK

POOCHERGAME RESERVE

DESERT CAMPCONS PARK

Naroo

Brecon

Coolami

Watinga

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Glengyle

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Bunns Springs

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SHAUGH

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KEITH

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Wolseley

Serviceton

MOUNT MONSTERCONSERVATION PK

Tatiara

Creek

Nalang

Creek


Datum GDA 94 - Projection UTM MGA Zone 54

Marla

GROUNDWATER SUB-AREAS IN THE TATIARA PWA

Tatiara Prescribed Wells Area

Figure 4

AV3: 200454-012

SOU

TH

A

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RA

LIA

VIC

TO

RIA

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450000

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Track


ORIGINALLY AV3: 200164-001

PART ZONE 9A

ZONE 8A

PART ZONE 7A

WIRREGA

CANNAWIGARANORTH

PENDLETONSTIRLING

WILLALOOKA

1

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456

7

2WIRREGA Management sub-area

200454-010

EastWest

Ele

vatio

nin

metr

es

(AH

D)

0

-100

100

-200

Molineaux Sand

Padthaway Formation and undifferentiated Quaternary

Bridgewater Formation: Fine to coarse shelly quartzsandstone of stranded coastal dune and beach deposits

Coomandook Formation: Marine fossiliferoussandy limestone

Parilla Sand and undifferentiated Tertiary

Murray Group Limestone: Bryozoal and shelly limestone

Ettrick Formation: Glauconitic andcarbonaceous calcareous clay

Buccleuch Formation: Carbonaceous clay, loosec sand with thin limestone bedsarbonaceous

Renmark Group: Carbonaceous clay andsandy clay, with interbedded quartz sand

Granite and microgranite

Water table

?

??

?

Figure 5 Schematic east-west geological cross section of the Tatiara PWA.

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Serviceton

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STR 113

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WLL 108

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STR 123

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PET 15

PET 4CAN 11

CAN 14

CAN 13

CAN 12

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WRG 20

WRG 23WRG 11

WRG 9

TAT 18

TAT 4

TAT 9

TAT 26

TAT 25

TAT 10

SEN 4

SEN 12

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SEN 3

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TAT 23

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WRG 110

WRG 111

PET 102

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WRG 114

WRG 116

TAT 108

TAT 107

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PET 105

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CAN 103

WRG 121

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WLL 22WLL 23

SHG 2SHG 5




LOCATION OF CURRENTWATER LEVEL MONITORING WELLS

JUNE2000

TATIARA PRESCRIBED WELLS AREA

Figure 6AV3: 200454-013

# Observation well and numberTAT 9


#S#S

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Girraween

Kangaringa

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Bunns Springs

Berum

KEITH

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Cholla

Wirrega

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Brimbago

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Tarkeerip

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BORDERTOWN

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Lowan Vale

Buckingham

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SHAUGH

SENIOR

STIRLING

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CANNAWIGARA

McCALLUM

FISK

LAFFER

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MAKIN


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LOCATION OF CURRENTSALINITY OBSERVATION WELLS

JUNE 2000


Figure 7

AV3: 200454-014

Observation well numberTAT 108#

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LOCALITY

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ADELAIDE


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SEE ENLARGEMENT

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AV3: 200164-003

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Lowan Vale

Buckingham

Cannawigara

BORDERTOWN

KEITH

Mundulla

Wolseley

Serviceton

STR 15

WRG 22

WLL 20

WRG 109

STR 113

WRG 113

WLL 104

WLL 105

WLL 107WLL 108

PET 103

WRG 117

PET 15

PET 4

CAN 11

CAN 14

CAN 13

CAN 12

CAN 16

WRG 18WRG 27

WRG 20

WRG 23

WRG 11

WRG 9

TAT 18

TAT 4

TAT 9

TAT 26

TAT 25

TAT 10

SEN 4

SEN 12

SEN 15

SEN 13

SEN 8

SEN 2

SEN 3

SEN 6

SEN 9

SEN 14 SEN 5

TAT 24

PET 14

WRG 112

WRG 110

PET 102

TAT 108

TAT 107

PET 104

PET 105

CAN 104

CAN 103

Originally AV3: 200164-004

#S

#S

#S

#S

#S

#S#S

#S

#S

#S

#S

#S

Moomba

Ceduna

Tarcoola

ADELAIDE

Oodnadatta

Coober Pedy


Port Augusta

Port Lincoln

Mount Gambier

Marla

SOU

TH

A

UST

RA

LIA

VIC

TO

RIA

450000

450000

475000

475000

5975

000 5975000

6000

000 6000000

6025

000 6025000


Waterbody

Creek

Railway

Hundred boundary

Homestead%

Town%

National Park

Highway

Secondary road

Minor road

Track



GENERALISED WATER TABLE ELEVATIONZONES IN THE UNCONFINED AQUIFER


Figure 8

AV3: 200454-015

Water table elevation -m (AHD)

20 - 2525 - 3030 - 3535 - 4040 - 4545 - 5050 - 5555 - 6060 - 6565 - 70

Water table elevation - m (AHD)

# 20 - 30# 30 - 35# 35 - 40# 40 - 45# 45 - 50# 50 - 70

$

$

$

%

%

%

%

%

%

%

%

%

%

%

%

%

%

%

%

%

%

%

%

%

%

%

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#

#

#

#

#

#

#

#

#

#

#

#

#

#

#

# #

#

#

#

#

#

#

#

#

#

#

#

#

#

#

#

#

#

##



ABERDOURCONS PARK

POOCHERGAME RESERVE


Naroo

Brecon

Coolami

Watinga

Glenpark

Glengyle

Girraween

Kangaringa

Didicoolum

Senior Park

Bunns Springs

Custon

MT SHAUGH

MT MONSTER

SUGARLOAF HILL

MundullaSwamp

WIRREGA

TATIARA

SHAUGH

SENIOR

STIRLING

PENDLETON

WILLALOOKA

CANNAWIGARA

McCALLUM

FISK

LAFF

ERPE

THER

ICK

MAKIN


ARCHIBALD

Berum

Cholla

Wirrega

Brimbago

Banealla

Tarkeerip

Alice Park

Willalooka

Lowan Vale

Buckingham

Cannawigara

BORDERTOWN

KEITH

MundullaWolseley

Serviceton

STR 22 STR 12

STR 2 STR 14STR 15

STR 9STR 17

STR 13

STR 8

WRG 22WLL 7

WLL 20

STR 21

STR 23

STR 24STR 111

STR 114

STR 112

WRG 109

STR 113

STR 110

WRG 113

WLL 104

WLL 105WLL 106

WLL 107WLL 108

STR 115

STR 116

STR 117

PET 103

WRG 117

STR 119

WRG 122

STR 118

PET 15

PET 4CAN 11

CAN 14

CAN 13

CAN 12

CAN 16

WRG 18WRG 27

WRG 20

WRG 23WRG 11

WRG 9

TAT 18

TAT 4

TAT 9

TAT 26

TAT 25

TAT 10

SEN 4

SEN 12

SEN 15

SEN 13

SEN 8

SEN 2

SEN 3

SEN 6

SEN 9

SEN 14 SEN 5

TAT 24TAT 20

TAT 23

PET 14

WRG 112

WRG 110WRG 111

TAT 106

WRG 114

WRG 116

TAT 108

TAT 107

PET 104

PET 105

CAN 104

CAN 103

WRG 121

WLL 22

WLL 23

-3.5 -13.8

0.0-7.1

-6.6

-6.4-5.9

-8.4

-5.9

3.30.0

0.0

-9.1

-3.5

-8.1-4.7

-9.9

-8.1

-6.6

-10.1

-3.9

0.0

0.0

-7.90.0

-7.6-12.0

-6.6

-4.7

-9.1

3.2

0.0

0.0

3.6

-14.0

3.5

4.22.2

1.1

1.5

0.0

1.7

5.98.3

9.6

0.01.0

0.5

0.0

-4.4

-2.9

0.2

1.2

-0.4

2.2

1.2

1.7

2.4

2.5

1.2

1.9

2.6

2.6

1.5 1.6

3.7

2.0

1.0

0.7

3.9

4.41.0

1.1

0.0

3.2

4.8

2.2

0.9

2.2

2.1

3.1

2.2

0.0

0.0

#S#S

#S

#S

#S#S

#S

#S

#S

#S#S

#S

Moomba

Ceduna

Tarcoola

ADELAIDE

Oodnadatta

Coober Pedy


Port Augusta

Port Lincoln

Mount Gambier

Marla

+5

-2.5

-5 0

0 to -5

0 to +5Greater than +5

Groundwater level trends (cm/year)

Greater than -5

# Observation well and numberSEN 4

Groundwater level trend contourin metres per year (cm/year)+5

Annual groundwater level trend (cm/year)2.2

Rising

Declining

SOUT

H A

USTR

ALIA

VICT

ORIA

450000

450000

475000

475000

5975

000 5975000

6000

000 6000000

6025

000 6025000

Waterbody

Creek

Railway

Hundred boundary

Homestead%

Town%

National Park





WATER LEVEL TRENDS IN THEUNCONFINED AQUIFER AT END OF

1998-1999 IRRIGATION SEASON


Figure 9AV3: 200454-016


$

$

$

%

%

%

%

%

%

%

%

%

%

%

%

%

%

%

%

%

%

%

%

%

%

%

#

# #

# # ####

##

###

# #

##

#

#

##

#

#

#

#

#

#

#

#

##

#

####

#

##

#

#

##

#

##

##

#

#

###

#

##

#

#

##

#

#

#

#

#

#

#

#

#

#

#

#

#

#

#

#

#

#

#

#

##

#

#

#

#

#

#

#

#

#

#

#

#

#

#

#

#

#

#

##

#

# ##

#

#

#

#

##

##

#

#

#

#

#

##

#

#

#

#

#

#

#

#

#

#

#

#

#

##

#

#

#

#

#

#

Naroo

Coolami

Watinga

Glenpark

Glengyle

Girraween

Kangaringa

Didicoolum

Senior Park

Bunns Springs

Berum

KEITH

Custon

Cholla

Wirrega

Wolseley

Brimbago

Banealla

Mundulla

Tarkeerip

Serviceton

Alice Park

BORDERTOWN

Willalooka

Lowan Vale

Buckingham

Cannawigara

MT SHAUGH

MT MONSTER

SUGARLOAF HILL

MundullaSwamp

WIRREGA

TATIARA

SHAUGH

SENIOR

STIRLING

PENDLETON

WILLALOOKA

CANNAWIGARA

McCALLUM

FISK

LAFF

ERPE

THER

ICK

MAKIN


ARCHIBALD

STR 236

STR 201STR 210

STR 256

STR 212

PET 200 PET 205

STR 105STR 106

WRG 104WRG 200

WRG 219

STR 243

WLL 103

STR 234

STR 246

STR 207

STR 259

STR 217

WLL 201

STR 242

WLL 202

STR 252

WRG 109

WRG 205

STR 115

STR 117

STR 121

STR 123

PET 201PET 202PET 203

CAN 102

WRG 201

WRG 206WRG 202

WRG 207

WRG 103 WRG 203WRG 208

WRG 209WRG 210

TAT 101

TAT 102WRG 211

WRG 213WRG 214

WRG 107

WRG 204

WRG 215

WRG 108

WRG 216WRG 217

WRG 218

TAT 107

SEN 17SEN 16

PET 204

WRG 220

# #

##

# #

#

#

##

###

# #

##

#

##

#

#

#

#

##

###

#

#

##

#

#

#

#

##

##

#

#

###

#

##

#

#

#

#

#

#

#

#

#

#

#

#

#

#

#

#

#

#

#

#

#

#

#

#

#

##

#

#

%

STIRLING

PENDLETON

KEITH

Brimbago

PET 200 PET 205

STR 101STR 221 STR 200

STR 102

STR 223

STR 224

STR 255STR 103

STR 225STR 226STR 227

STR 201STR 104

STR 105STR 229

STR 106

STR 260STR 231

STR 237

STR 243

STR 232

STR 203

STR 233STR 204


STR 244

STR 206

STR 257STR 228

STR 236

STR 247

STR 207

STR 259

STR 208STR 209

STR 258STR 210

STR 239

STR 211

STR 248STR 249

STR 250

STR 212

STR 214STR 215

STR 240

STR 216

STR 241

STR 217

STR 218

STR 242

STR 252

STR 251

STR 202

STR 111

STR 112

STR 219

STR 256

STR 115

STR 254

STR 121

STR 123

STR 128

PET 201

PET 204


GENERALISED SALINITY DISTRIBUTIONIN THE UNCONFINED AQUIFER

Tatiara Prescribed Wells AreaFigure 10

AV3: 200454-017

440000

440000

450000

450000

5990

000 5990000

6000

000 6000000

450000

450000

475000

475000

5975

000 5975000

6000

000 6000000

6025000

#S

#S#S

#S

Port Augusta

Port Lincoln

Mount Gambier

LOCALITY

ENLARGEMENT


ADELAIDE



SEE ENLARGEMENT

SOUT

H A

USTR

ALIA

VICT

ORIA

Originally AV3: 200164-006

Salinity zones (mg/L)0 - 20002000 - 30003000 - 50005000 - 70007000 - 10000

# 0 - 2000# 2000 - 3000# 3000 - 5000# 5000 - 7000# 7000 - 10000

Salinity (mg/L)

$

$

$

%

%

%

%

%

%

%

%

%

%

%

%

%

%

%

%

%

%

%

%

%

%

%

#

# #

# # ###

##

###

# #

##

#

#

#

#

#

#

#

#

#

#

##

#

####

#

##

#

#

##

##

##

#

#

###

#

#

##

#

##

#

#

#

#

#

#

#

#

#

#

#

#

#

#

#

#

#

#

#

#

##

#

#

#

#

#

#

#

#

#

#

#

#

##

#

##

#

#

#

##

#

#

#

#

##

#

#

#

#

#

#

#

#

#

#

#

#

##

#

#

#

#

#

#

#

#



ABERDOURCONS PARK


POOCHERGAME RESERVE


Naroo

Brecon

Coolami

Watinga

Glenpark

Glengyle

Girraween

Kangaringa

Didicoolum

Senior Park

Bunns Springs

Berum

KEITH

Custon

Cholla

Wirrega

Wolseley

Brimbago

Banealla

Mundulla

Tarkeerip

Serviceton

Alice Park

BORDERTOWN

Willalooka

Lowan Vale

Buckingham

Cannawigara

MT SHAUGH

MT MONSTER

SUGARLOAF HILL

MundullaSwamp

TAT 108 TAT 110

LAF 101

PET 200 PET 205STR 201

STR 104

STR 105STR 229

STR 106

STR 107

STR 260

WRG 104

WRG 200

WRG 219

STR 243

STR 232

STR 203

STR 234

STR 206

STR 236

STR 246

STR 247

STR 207

STR 208

STR 239

STR 250

STR 212

STR 213

STR 241STR 217

STR 242

WLL 202

STR 252

STR 251

WRG 109

STR 113

WRG 205

STR 110

WRG 113

STR 219

WLL 105

STR 256

WLL 106

WLL 107 WLL 108

STR 115

STR 116

STR 117

WRG 117

STR 119

WRG 122

PET 201

PET 202

PET 203

CAN 101

WRG 201

WRG 206

WRG 202

WRG 207

WRG 203WRG 208

WRG 210

SEN 18

TAT 102

WRG 211

WRG 213

WRG 204

WRG 215

TAT 104

WRG 216WRG 217

WRG 218

WRG 112

WRG 110

WRG 111

TAT 106

WRG 114

WRG 116

TAT 107, 109

PET 104

PET 105

SEN 17SEN 16

CAN 20

CAN 104

CAN 103

WRG 121

PET 204

WRG 220

SHG 4

WLL 103WLL 104 TAT 101

WIRREGA

TATIARA

SHAUGH

SENIOR

STIRLING

PENDLETON

WILLALOOKA

CANNAWIGARA

McCALLUM

FISK

LAFF

ERPE

THER

ICK

MAKIN


ARCHIBALD

$

%

# #

##

# #

#

##

###

# #

##

#

#

#

#

#

##

###

#

#

##

#

#

#

##

##

#

#

###

#

#

##

#

#

#

#

#

#

#

#

#

#

#

#

#

##

#

#

#

#

#

#

#

#

STIRLING

PENDLETON

KEITH

Brimbago

PET 200PET 205

STR 101 STR 221 STR 200STR 102

STR 223

STR 255STR 103


STR 201 STR 104

STR 105STR 229

STR 106

STR 260

STR 243

STR 232

STR 203

STR 233STR 204

STR 222 STR 205 STR 235

STR 244

STR 206

STR 257

STR 228

STR 236

STR 247

STR 207

STR 208STR 209

STR 258STR 210

STR 239

STR 211


STR 212

STR 213

STR 214STR 215

STR 216

STR 241

STR 217

STR 218

STR 242

STR 252

STR 251

STR 202

STR 111

STR 114

STR 112

STR 113

STR 219

STR 220

STR 256

STR 115

STR 116

STR 117

STR 119

STR 254

PET 201

PET 104

PET 204


Annual salinity trend contour - mg/L (calculated from linear regression of all availabledata at end of 1998-1999 irrigation season)+50

Annual salinity trends (mg/L)

# -50 to 0

# 0 to 10# 10 to 30# 30 to 50# 50 to 100# Greater than 100

Decreasing

Increasing

Salinity increase greater than 50mg/L per year


Figure 11

AV3: 200454-018Observation well numberSHG 4

440000

440000

450000

450000

5990

000 5990000

6000

000 6000000

450000

450000

475000

475000

5975

000 5975000

6000

000 6000000

6025000

#S

#S#S

#S

Port Augusta

Port Lincoln

Mount Gambier

LOCALITY

ENLARGEMENT


ADELAIDE



SEE ENLARGEMENT

+50

+50

+50

+50

+50

+50

+50

+50

+50

+50

SOUT

H A

USTR

ALIA

VICT

ORIA


SALINITY TRENDS IN THEUNCONFINED AQUIFER AT END OF

1998-1999 IRRIGATION SEASON

$

$

$

%

%

%

%

%

%

%

%

%

%

%

%

%

%

%

%

%

%

%

%

%

%

%



ABERDOURCONS PARK

POOCHERGAME RESERVE


Naroo

Brecon

Coolami

Watinga

Glenpark

Glengyle

Girraween

Kangaringa

Didicoolum

Senior Park

Bunns Springs

Custon

MT SHAUGH

MT MONSTER

SUGARLOAF HILL

MundullaSwamp

WIRREGA

TATIARA

SHAUGH

SENIOR

STIRLINGPENDLETON

WILLALOOKA

CANNAWIGARA

McCALLUM

FISK

LAFFER

PETHERICK

MAKIN


ARCHIBALD

Berum

Cholla

Wirrega

Brimbago

Banealla

Tarkeerip

Alice Park

Willalooka

Lowan Vale

Buckingham

Cannawigara

BORDERTOWN

KEITH

MundullaWolseley

Serviceton


Tatiara

Creek

Nalang

Creek


Datum GDA94 - Projection UTM MGA Zone 54

#S#S

#S

#S

#S#S

#S

#S

#S

#S#S

#S

Moomba

Ceduna

Tarcoola

ADELAIDE

Oodnadatta

Coober Pedy


Port Augusta

Port Lincoln

Mount Gambier

Marla

IRRIGATION ACTIVITY DISTRIBUTION FOR1998-1999 IRRIGATION SEASON


Figure 12AV3: 200454-019

Irrigation activity distribution(not actual layout of irrigation area)

SOUT

H A

USTR

ALIA

VICT

ORIA

450000

450000

475000

475000

5975

000 5975000

6000

000 6000000

6025

000 6025000

Waterbody

Creek

Railway

Hundred boundary

Homestead%

Town%

National Park




#S

#S

#S

#S

#S

#S

#S

#S

#S

#S

#S

WIRREGA

LAFFER

JOYCE

FOX

GLYDE

TATIARAWELLS

SHAUGHCOOMBE

SENIOR

HYNAM

SPENCE

GREY

BRAY

MAKIN

ROSS

FIELD

BINNUM

COLES

STIRLING

PETHERICK

SANTO

JESSIE

PEACOCK

SHORT

RICHARDS

NEVILLE

BENARA

BEEAMMA

SMITH

MESSENT

GEEGEELA

ARCHIBALD

SYMON

YOUNG

MARCOLLAT

CONMURRA

MCNAMARA

MCCALLUM

PENDLETON

PENOLA

MINECROW

COLEBATCH

LANDSEER

JOANNA

DUFFIELD

WILLALOOKA

BLANCHE

RIDDOCH

BOWAKA

GAMBIER

COMAUM

GLEN ROY

LACEPEDE

MAYURRA

TOWNSEND

KENNION

PARSONS

CAROLINE

WATERHOUSE

CANNAWIGARA

LOCHABER

WOOLUMBOOL

MONBULLA

MINGBOOL

ROBERTSON

HINDMARSH

KILLANOOLA

MACDONNELL

NANGWARRY

NARACOORTE

RIVOLI BAY

KONGORONG

LAKE GEORGE

MURR

ABIN

NA

MOUNT BENSON

MOUNT MUIRHEAD

Robe

KEITH

PENOLA

Lucindale

Padthaway

Beachport

MILLICENT

BORDERTOWN

Kingston SE

NARACOORTE

MOUNTGAMBIER

ZONE 9A

ZONZONE 1A

ZONE 2A ZON

ZONE 3A

ZON

ZONE 4A ZON

ZONE 5A ZON

ZONE 6A ZON

ZONE 7A ZON

ZONE 8A ZON

MILLICENT

MONBULLA

WIRREGA

KEITH

NARACOORTE

KINGSTON

Management zone

Hundred boundary


AV : 200454_058

SOUT

H A

USTR

ALIA

VICT

ORIA

Figure 13

Tatiara Prescribed Wells AreaPROPOSED MANAGEMENT ZONES

FOR THE TERTIARY CONFINED SAND AQUIFER

Prepared November 2000


38°

38°37

°37°

36°

36°

140°

140°

141°

141°

37

Appendix A

Estimated irrigation requirements and crop area ratios

for the Tatiara Prescribed Wells Area

38

CropArea

IrrigationRequirement (mm)

CropRatio

Reference crop 634 1.0Annual clover seed 263 2.4Canola seed 73 8.7Cereals 136 4.7Chinese cabbage seed 73 8.7Citrus 272 2.3Coriander seed 73 8.7Fenugreek seed 73 8.7Field Beans/Lupins/Peas/Vetch 101 6.3Garlic 122 5.2Gladiolus 436 1.5Grass seed 405 1.6Haifa seed 394 1.6Linseed 73 8.7Kale seed 141 4.2Lucerne hay 551 1.2Lucerne ‘full’ seed or fodder 1.1Lucerne seed (13) + autumn fodder 1.5Lucerne spring fodder + seed 1.3Lucerne seed (16) 1.6Lucerne seed (13) 1.9Maize 290 2.2Medic seed 120 5.3Mustard seed 73 8.7Onions 343 1.8Pasture 601 1.1Pasture starter, finisher 100 6.3Perrenial clover seed 394 1.6Potatoes 365 1.7Pumpkins 345 1.8Primrose 73 8.7Proteas 70 9.0Radish seed 124 5.1Sainfoin seed 515 1.2Sorghum/Millet 374 1.7Spring lucerne 4.3Spring and autumn lucerne 2.8Starter or finisher lucerne 6.3Sunflower 345 1.8Turf areas 634 1.0Vines 282 2.2Winter crop then Sorgham/Millet 407 1.6

39

Appendix B

Bore hydrographs and salinity graphs

40

Sub-Area 2Confined Aquifer

Observation Well WRG025

20

22

24

26

28

30

75 81 86 92 97 03

Year

Ele

vati

on

(m

AH

D) Water Level

Sub-Area 2Observation Well Wrg112

45

47

49

51

53

55

75 81 86 92 97 03

Year

Ele

vati

on

(m

AH

D)

0

1000

2000

3000

4000

5000

Sal

init

y (m

g/L

)

Water Level

Salinity

Sub-Area 2Observation Well Wrg116

49

51

53

55

57

59

75 81 86 92 97 03

Year

Ele

vati

on

(m

AH

D)

0

1000

2000

3000

4000

5000

Sal

init

y (m

g/L

)

Water Level

Salinity

41

Sub-Area 3Observation Well Wll108

24

26

28

30

32

34

75 81 86 92 97 03

Year

Ele

vati

on

(m

AH

D)

1000

2000

3000

4000

5000

6000

Sal

init

y (m

g/L

)

Water Level

Salinity

Sub-Area 3Observation Well Wll106

20

22

24

26

28

30

75 81 86 92 97 03

Year

Ele

vati

on

(m

AH

D)

0

1000

2000

3000

4000

5000

Sal

init

y (m

g/L

)

Water Level

Salinity

Sub-Area 6Observation Well Pet104

40

42

44

46

48

50

75 81 86 92 97 03

Year

Ele

vati

on

(m

AH

D)

1000

2000

3000

4000

5000

6000

Sal

init

y (m

g/L

)

Water Level

Salinity

42

Sub-Area 6Observation Well Pet105

40

42

44

46

48

50

75 81 86 92 97 03

Year

Ele

vati

on

(m

AH

D)

1000

2000

3000

4000

5000

6000

Sal

init

y (m

g/L

)

Water Level

Salinity

Sub-Area 7Observation Well Str115

20

22

24

26

28

30

75 81 86 92 97 03

Year

Ele

vati

on

(m

AH

D)

3000

4000

5000

6000

7000

8000

Sal

init

y (m

g/L

)

Water Level

Salinity

Sub-Area 7Observation Well Str117

20

22

24

26

28

30

75 81 86 92 97 03

Year

Ele

vati

on

(m

AH

D)

2000

3000

4000

5000

6000

7000

Sal

init

y (m

g/L

)

Water Level

Salinity

43

Sub-Area Zone 7AObservation Well Tat108

56

58

60

62

64

66

75 81 86 92 97 03

Year

Ele

vati

on

(m

AH

D)

0

1000

2000

3000

4000

5000

Sal

init

y (m

g/L

)

Water Level

Salinity

Sub-Area Zone 7AConfined Aquifer

Observation Well Tat027

66

68

70

72

74

76

75 81 86 92 97 03

Year

Ele

vati

on

(m

AH

D) Water Level

Sub-Area Zone 7AObservation Well Tat107

60

62

64

66

68

70

75 81 86 92 97 03

Year

Ele

vati

on

(m

AH

D)

0

1000

2000

3000

4000

5000

Sal

init

y (m

g/L

)

Water Level

Salinity

44

Sub-Area Zone 8AObservation Well Sen009

60

62

64

66

68

70

75 81 86 92 97 03

Year

Ele

vati

on

(m

AH

D) Water Level

Sub-Area Zone 8AObservation Well Sen016

0

1000

2000

3000

4000

5000

75 81 86 92 97 03

Year

Sal

init

y (m

g/L

) Salinity


Observation Well SHG005

55

57

59

61

63

65

75 81 86 92 97 03

Year

Ele

vati

on

(m

AH

D) Water Level

45


Observation Well SHG006

50

52

54

56

58

60

75 81 86 92 97 03

Year

Ele

vati

on

(m

AH

D) Water Level

Sub-Area Zone 9AObservation Well Shg004

0

1000

2000

3000

4000

5000

75 81 86 92 97 03

Year

Sal

init

y (m

g/L

)

Salinity

46

Appendix C

Stock Water Use Consumption Figures

47

STOCK WATER USE CONSUMPTION FIGURES

Sheep (dry pasture) 7 Litres/HeadSheep (irrigated pasture) 4 Litres/HeadLambs (dry pasture) 2.5 Litres/HeadLambs (irrigated pasture) 1 Litres/HeadBeef Cattle 45 Litres/HeadCalves 23 Litres/HeadDairy Cattle (in lactation) 68 Litres/HeadDairy Cattle (dry) 45 Litres/HeadHorses (working) 55 Litres/HeadHorses (grazing) 36 Litres/HeadSows 23 Litres/HeadPigs 11 Litres/HeadPoultry (100) 3.2 Litres/HeadTurkeys (100) 5.5 Litres/Head

water resource assessment: tatiara prescribed wells area ... · 4 primary industries and resources...

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