Department of Conservation and Land Management...Electronic 1 Jodie Watts – Department of...

Department of Conservationand Land Management

Buntine-Marchagee Natural DiversityRecovery Catchment Surface WaterManagement PlanRev 1

March 2003

Department of Conservation andLand Management

Buntine-Marchagee Natural Diversity Recovery

Catchment Surface Water Management Plan

Rev 1

March 2003

Sinclair Knight Merz Pty LimitedACN 001 024 095ABN 37 001 024 0957th Floor, Durack Centre263 Adelaide TerracePO Box H615Perth WAAustralia 6001Telephone: +61 8 9268 4400Facsimile: +61 8 9268 4488

COPYRIGHT: The concepts and information contained in

this document are the property of Sinclair Knight Merz Pty

Ltd. Use or copying of this document in whole or in part

without the written permission of Sinclair Knight Merz

constitutes an infringement of copyright.

Department of Conservation and Land Management

Catchment Scale Surface Water Management Report:Buntine-Marchagee Sub-Catchment

WV02367:R31SXAPAF_CATCHMENTREPORT.DOC Rev 1 PAGE i

Contents

Executive Summary............................................................................ iiiStudy Scope and Objectives........................................................................ iiiStudy Outcomes .......................................................................................... iiiStudy Conclusions and Recommendations..................................................v

1. Introduction.................................................................................... 11.1 Background to this Study .................................................................11.2 Study Area and Hydrology Issues....................................................11.3 Benefits of Surface Water Management Planning............................21.4 Study Scope ....................................................................................31.5 Structure of report............................................................................3

2. Study Methodology........................................................................ 52.1 Initial Briefing and meeting with stakeholders for demonstration site52.2 Literature Review.............................................................................52.3 Data Collection ................................................................................62.4 Landholder Participation ..................................................................62.5 Development of Demonstration Site Surface Water ManagementPlan and Report ........................................................................................72.6 Development of Individual Surface Water Management Plans.........7

3. Statement of Current Surface Water Hydrology.......................... 93.1 Location...........................................................................................93.2 Geology and Landforms.................................................................113.3 Soils...............................................................................................123.4 Existing Hydrology .........................................................................14

3.4.1 Surface water .................................................................................143.4.2 Groundwater ..................................................................................15

4. Best Practice Surface Water Management Planning ................ 205. Landholder Participation............................................................. 236. Catchment-scale Surface Water Management Planning .......... 247. Conclusions and Recommendations......................................... 288. Acknowledgements ..................................................................... 299. References ................................................................................... 30Appendix A Demonstration Site ReportAppendix B Individual Landholder SWMPsAppendix C Soil DescriptionsAppendix D Project Information Provided to LandholdersAppendix E Landholder Authorisation to Use Information

Collected Proforma Sheet



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Document History and StatusRev. Date Reviewed By Approved By Revision DetailsDraftRev 0

22/01/03 Bob Taylor Peter French Issued to DCLM as Draft

Rev 1 25/03/03 Bob Taylor Peter French Issued to DCLM as Final

Distribution of copies:Copy No. Quantity Issued To1 3 Jodie Watts – Department of Conservation and Land Management

Electronic 1 Jodie Watts – Department of Conservation and Land Management

Printed: 24 March, 2003Last Saved: 24 March, 2003File Name: I:\WVES\02300\WV02367\Rep020920\Final Reports\R31sxapaf_Catchmentreport.Doc

Author: Peter French / Simon AbbottProject Manager: Peter FrenchName of Organisation: Department of Conservation and Land ManagementName of Project: Buntine-Marchagee Natural Diversity Recovery Catchment Surface Water

Management Plan.Name of Document: Surface Water Management Plans - Catchment ReportDocument Version: Rev 1Project Number: WV02367



WV02367:R31SXAPAF_CATCHMENTREPORT.DOC Rev 1 PAGE iii

Executive SummaryStudy Scope and ObjectivesSinclair Knight Merz (SKM) has been engaged to conduct a Surface WaterManagement Planning Project within a section of the Buntine–Marchagee NaturalDiversity Recovery Catchment for the Department of Conservation and LandManagement (DCLM).

The study area is centred approximately 40 kilometres south east of Coorow, which isapproximately 230 kilometres north-north-east of Perth.

The Buntine-Marchagee catchment is a natural diversity recovery catchment declaredunder the State Salinity Strategy. Recovery catchments aim to conserve naturaldiversity by implementing well-planned work with local communities and surroundinglandholders. This particular catchment is different to other recovery catchmentsbecause although it is threatened by rising water tables, it has not yet reached a criticalstage. The main watercourse through this catchment is a naturally saline braidedchannel, a wetland form typical of the Eastern Wheatbelt.

This study compliments other studies DCLM have commenced within the catchment.

This Surface Water Management Planning Project has the following objectives:� To prepare a Surface Water Management Plan to determine actions required to

control surface water movement; and� To assist the Recovery Catchment Steering Committee in understanding the

options for surface water control.

This study was conducted in a series of steps including;� Initial Briefing with stakeholders;� Literature Review;� Landholder Participation;� Development of Demonstration Site Surface Water Management Plan and

Report;� Development of Individual Surface Water Management Plans;� Development of Individual Surface Water Management Plan Reports;� Development of Catchment Scale Surface Water Management Plan and Report;

and� Presentations on the Study Outcomes.

Study Outcomes24 out of 27 landholders within the study area participated in the study and providedthe transfer of knowledge required for Sinclair Knight Merz to develop the SurfaceWater Management Plans (SWMPs).

The study area consists of three distinct landforms:� A north-south oriented upland ridge which is located approximately in the centre

of the study area, which consist of clays, clay loams and loams and duplex sandygravels;



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� The zone of ancient drainage, consisting of the valley floor of the arterialdrainage system; and

� The sandplain landscape, which consists of grey, white or more often, yellowquartz sand.

Approximately 75% of the study area had soils mapped in 1997-1998 and digitisedinto AutoCAD files (by David Kessell of Moora Farm Consultancy) approximatelyfive years ago. This information was reinterpreted and a simple, meaningful set of soiltypes and descriptions for the study area was developed. Nine standard soildescriptions were developed. This was a reinterpretation of the original soilsmapping, not just a simple reclassification exercise, as many of the soil descriptionsdiffered across property boundaries and substantial editing of the digital data wasnecessary to produce a coherent soils map of the study area.

The soils of the remaining landholders properties, within the study area, not coveredby the original (1997-1998) mapping, were mapped as part of this study. Thisinvolved additional field inspection time for those properties.

The nine soil descriptions developed, along with a summary of their soil waterbehaviour are listed in Table ES-1.

� Table ES-1 Soil Types within the study areaSoil Type Soil Water Behaviour

Deep White/Grey Sand Infiltration is rapid, although can have-Non-wettingcharacteristics

Gravelly Sand and Shallow Sand overGravel

Susceptible to waterlogging in areas of low slope

Grey Clay Has the capacity to generate a high rate of runoffRed Clay Has the capacity to generate a high rate of runoffRed Clay Loam Has the capacity to generate a high rate of runoffRed/Brown Loam Sheet and rill erosion of the lighter surface profile can occur on

sloping ground and waterlogging where there is low slope. Thissoil type has a strong capacity to generate runoff.

Alluvial River Soils Complex Spatially variable infiltration and runoff capacityYellow Sandplain Rainfall infiltration is rapidYellow Sandy Loam Water erosion can occur on this soil type, mainly as a

consequence of intense rainfall

During the site inspections with individual landholders their knowledge on surfacewater management and control was obtained and is summarised below:� Most landholders did not perceive strong links between surface water

management and salinity control on their property;� When considering earthworks planning for salinity control most landholders did

not distinguish between surface and ground water;� Many of the landholders, particularly those on the sandplain areas, were very

interested to learn more about groundwater and its movement in the landscape;� Most landholders were very knowledgeable on details such as depths of bores,

water quality and water levels in bores. Many of them provided the informationfrom memory;

� All landholders interviewed were very co-operative. They perceived this study asa first step towards doing something about salinisation of water supplies and land,within the study area; and



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� In most landholders’ minds, salinity was clearly the most importantenvironmental threat to their enterprise.

In the study area the following surface water management issues have been identifiedand are addressed within this study:� Waterlogging on flats and lower slopes;� Flooding on lower slopes;� Soil erosion on steeper slopes;� Poor water catchment into dams;� Transfer of large surface flows without causing erosion; and� Relatively fresh shallow seepage causing soil salinity.

Surface water management controls appropriate for each of these issues are describedwithin this report. All controls described and prescribed for the individual landholderproperties are consistent with those described within Keen (1998) and Keen (2001).

Existing surface water management strategies varied between landholders, rangingfrom minimal to comprehensive. Most were adequate and some adequate in design ifnot in maintenance.

The adoption of minimum tillage cropping practices by most landholders within thestudy area has resulted in the landscape generating significantly less runoff per unitarea. This is the main reason for surface water management infrastructure either notbeing maintained, or in some cases removed or “thinned out”.

There are economic benefits from surface water management earthworks, particularlywhere levels of waterlogging causing clinical and sub-clinical damage to crops andpastures regularly occur (McFarlane et al, 1992).

Study Conclusions and RecommendationsA clear majority of the proposed surface water management earthworks are located inthe duplex soils landform zone. Most of the surface water management issues arelocated in this landform zone and earthworks are the appropriate means of addressingissues on these soil types.

Regional, catchment or multi-property scale works were generally not required tomanage surface water in this study area. All planned earthworks, apart from one, wereable to be started and ended within a single landholders property as adequate surfacewater disposal sites were found within property boundaries.

Using surface water management earthworks reductions in recharge and runoff in theorder of 10% can be achieved (Coles and Mahtab, 2000), on 26% of the study area(the duplex soils landform zone). However our lack of understanding of groundwatermovement in the sandplain landscape zone is limiting our ability to impact on 61% ofthe area.

Understanding the hydrology of the sandplain and its underlying regolith as well asthe hydrology of the river valley holds the key to protecting the biodiversity values ofthis study area from the threat of salinity.



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In order to further progress the understanding of how to protect biodiversity valueswithin the catchment from increased salinity the following recommendations aremade:

1) Surface water management controls described in the individual SWMPs(Appendix B) are implemented, particularly for those properties lying within theduplex landform area; and

2) Further investigations be conducted to gain better knowledge of the groundwatersystems throughout the catchment and particularly in the lake chain/river andsandplain landforms.



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1. Introduction1.1 Background to this StudyA 181,000ha area in the northern agricultural zone between Dalwallinu and Coorowhas become a recovery catchment for natural diversity under the State SalinityStrategy and is known as the Buntine – Marchagee Natural Diversity RecoveryCatchment. The Buntine-Marchagee catchment is the fifth natural diversity recoverycatchment declared under the State Salinity Strategy.

Natural diversity recovery catchments are identified in the State Salinity Strategybecause they have high natural diversity at risk from rising water tables and salinity.Recovery catchments aim to conserve natural diversity by implementing well-plannedwork with local communities and surrounding landholders. This particular catchmentis different to other recovery catchments because, although it is threatened by risingwater tables, it has not yet reached a critical stage. It is also a naturally saline braidedchannel, a wetland form typical of the Eastern and Northern Wheatbelt.

The Department of Conservation and Land Management (DCLM) is co-ordinatingpreparation of a recovery plan for the catchment. This involves close consultation withlocal landholders and other key stakeholders.

DCLM have established biological survey sites across the catchment as part of itssurvey work under the Salinity Strategy. In addition a steering committee has beenformed and has met to provide direction to the activities undertaken in the recoverycatchment.

Part of the steering committee's initial requirements for the recovery catchment projectwas to gain a better understanding of the hydrological situation within the catchment.As part of this a series of piezometers and observation bores have been installed acrossthe catchment and Sinclair Knight Merz (SKM) have been engaged to conduct aSurface Water Management Planning Project.

1.2 Study Area and Hydrology IssuesThe project has been undertaken within the specified study area, which is estimated tobe approximately 44,000 hectares. The study area was chosen on the basis that it:� Contains some of the steepest slopes with the recovery catchment;� Is representative of the western area (ie. contains areas of the rejuvenated

landscape and the re-worked sand landscape);� Has a high run-off potential due to the steeper slopes and heavier soil types

(associated with the rejuvenated landscape); and� Will allow a better level of understanding of the surface and shallow sub-surface

water movement in the reworked sands landscape to be developed.

The boundaries of the study area were extended outwards to the nearest naturalboundary (regional drainage line or watershed) to ensure that the study area was self-contained in terms of local surface water flow. The study area encompassed otherlandscape types not typically responsive to surface water management, although itallowed for some comparisons and discussion on the topic.




The study area is part of a landscape that developed as a sclerophyll woodland. Assuch almost all rainfall was intercepted by the vegetation. Prior to clearing of the 400mm average annual rainfall, it is estimated 396 mm would have evaporated, 1.2 mmwould have run off only some and would have infiltrated the soil (Sinclair KnightMerz, 2001). Similarly it is estimated that after clearing, from the same 400 mm ofrainfall, 372 mm evaporate, 12 mm runs off and 16 mm infiltrates to rechargegroundwater aquifers. The need for surface water management is largely driven bythis ten-fold increase in runoff since clearing. Such significantly larger volumes ofrunoff water on a landscape that has not evolved under such conditions leads toerosion, waterlogging and flooding. These forms of degradation can be managed bytwo different approaches.

The first approach is the management of day-to-day farming activities in a waterconscious manner such that runoff is minimised and infiltration is encouraged acrossall farmed land. This approach is management-dependent, varying with the skills andcapacities of individual managers, economics of farm enterprises and seasonalconditions.

The second approach is characterised by installation of surface water managementearthworks structures. This approach is management-independent and functions yearin, year out regardless of day to day management decisions and within a pre-determined range of seasonal conditions. This approach is preferred for this study asit provides controls that do not rely on individual landholder management decisions.

1.3 Benefits of Surface Water Management PlanningSurface water management earthworks on duplex soils are known to produceeconomic benefits to cropping and grazing enterprises. This is particularly true wherelevels of waterlogging causing clinical and sub-clinical damage to crops and pasturesregularly occur (McFarlane et al., 1992).

In general, the most effective economic incentive for landholders to undertake surfacewater management is the increased profit generated by increased yield of crops andpastures where waterlogging has been reduced (McFarlane et al., 1992).

In order to achieve co-ordinated, “on the ground” actions, it is essential that a welldocumented plan of action is prepared and committed to. The purpose of thiscatchment plan and the individual landholder SWMP’s is to facilitate this. Thisproject is part of a process designed to ensure that the appropriate actions for theprotection of the biodiversity and agricultural productivity of the area are included inlandholders’ property management plans.

Waterlogging is one of the known mechanisms providing recharge to groundwateraquifers. Surface water management strategies can reduce waterlogging and thusreduce the rate of recharge of the groundwater aquifer. In small agriculturalcatchments, surface water management earthworks have been shown to reduce peakflow from the catchment (Coles and Mahtab, 2000). It is hoped that reduced peakflows from farm land will reduce the impact of flooding on the wetlands.




1.4 Study ScopeThis study was performed to provide the DCLM with a Surface Water ManagementPlan and accompanying report for the Buntine-Marchagee Natural Diversity RecoveryCatchment. To achieve this all landholders within the study area were to beinterviewed and individual landholder surface water management plans formulatedand reports developed.

As defined in the scope of this study this report documents the methods used andresults obtained from the investigation of the surface water management issuesobserved and reported in the study area. It provides information and analysis on thesurface water control options for a section of the Buntine-Marchagee NaturalDiversity Recovery Catchment. This data will be used to develop a surface watermanagement strategy for the Recovery Catchment and will assist in planning on-ground works.

This project also aims to reduce the impact of erosion, waterlogging and floodingevents on wetlands. A significant threat to the biodiversity of these wetlands is risingsaline groundwater.

During the study Sinclair Knight Merz have consulted with landholders within thestudy area and in conjunction with the landholders, developed surface watermanagement plans for individual properties.

This report presents the results of this study. A separate report presents the plan for asurface water management demonstration site. It is the steering committees desire toconduct the implement the plan for the demonstration site to demonstrate theeffectiveness of surface water management as a tool to manage salinity.

The Surface Water Management Planning Project has the following objectives:� To prepare a Surface Water Management Plan to determine actions required to

control surface water movement;� To assist the Recovery Catchment Steering Committee in understanding the

options for surface water control.

There are three main outputs from the study:1) A catchment report. This provides a description of the study methodology and a

brief overview of the catchment.

2) The demonstration site catchment plan.

3) Individual landholder surface water management plans.

1.5 Structure of reportThe structure of the report is as follows:� A brief executive summary of the report;� An introduction describing the background to and context of the report (Section

1);� The study methodology (Section 2);




� A description of the current surface water hydrology situation within the studyarea (Section 3);

� Information regarding best practice surface water management planning (Section4);

� The outcomes of the landholder participation (Section 5);� A synthesis of the individual surface water management plans into a discussion

on the catchment surface water management plan (Section 6);� Conclusion reached from the study and recommendation for action from this

point (Section 7);� Acknowledgements (Section 8); and� References (Section 9).

A series of information generated during this study are included within theappendices:� The complete demonstration site report (Appendix A);� All 24 individual landholder surface water management plans (Appendix B);� A description of the soils data developed and used within this study (Appendix

C);� A copy of the information provided to landholders (Appendix D); and� A copy of the proforma landholder authorisations to use information collected

(Appendix E).




2. Study MethodologyThis study was conducted in a series of steps, each of which are described below:

2.1 Initial Briefing and meeting with stakeholders fordemonstration site

Initial briefing and catchment inspection was undertaken on 10 September 2002.

The demonstration site and its catchment were inspected on Wednesday 11th

September 2002 by Mr Bob Taylor, Mr Peter French and Mr Simon Abbott fromSinclair Knight Merz, Ms Jodie Watts representing DCLM and Mr Peter Whalerepresenting the Department of Agriculture. Mr John Stacey, the owner of much ofthe land in the catchment to this site, guided this inspection. The purpose of theinspection was to provide all members of the study team with an understanding of theissues and the nature of the demonstration site and to define the problems that wouldbe addressed by this study.

Earlier in the day, this same inspection team met with Ms Jan Muller, owner of landnorth of Buntine-Marchagee Road which receives discharge from the culvert inquestion. Mrs Muller showed aerial photographs to illustrate the location of surfacewater flows on her property and her concerns about proposals that might involve opencut deep drains across her property.

2.2 Literature Review

At the commencement of this study a search was conducted to acquire as muchinformation as possible on the demonstration site and the wider Surface WaterManagement Planning study area. No titles specifically referring to the hydrology ofthe area were found, however, general comment on the hydrology of the catchment tothe Upper Coonderoo River was published in a report on the Moore River Catchmentby Sinclair Knight Merz (2001) for the Water and Rivers Commission.

Publications dealing with the general subject of surface water management in theagricultural areas of Western Australia were identified and pertinent informationextracted. These provided information on the impacts on catchment water flows of theimplementation of surface water management works across a catchment. They alsoprovided information on the economic costs associated with issues such aswaterlogging and the costs and benefits of control of these issues.

Information obtained from the literature review have been incorporated throughout thereport and in particular into Sections 3 and 4.

Best practice techniques and methods for surface water management were investigatedand have been summarised in Section 4.




2.3 Data Collection

Land information was provided by DCLM as geographic information system (GIS)datasets. This included road networks, drainage patterns, DCLM piezometerlocations, slope classification, digital elevation model, topographical contours,regional soil/landform maps, cadastre and landholder information, and aerialphotography in the form of a digital orthophoto mosaic. Drilling notes from the recentDCLM drilling program were also provided.

Detailed soil maps of many properties within the study area were obtained by SKMfrom Mr David Kessell of Moora Farm Consultancy. These soil maps were generallypart of farm plans that had been developed about five years ago. Interpretation of thissoils data is described and presented in Appendix C.

For those properties not covered in this previous soil mapping, soils were mappedusing landholder knowledge obtained during landholder interviews.

2.4 Landholder Participation

Individual landholders within the study areas were contacted and times made forinspection of their properties. Mr Simon Abbott conducted interviews and inspectionswith the respective landholders, for the purpose of collecting information about thelandholders property, validating existing datasets, gaining an understanding of existingand planned surface water management and to develop recommended surface watermanagement actions. During these face to face interviews landholders were providedwith background information about the Buntine-Marchagee Natural DiversityRecovery Catchment and this surface water management planning project (seeAppendix D).

The field inspection enabled accurate mapping of physical features not visible in theaerial photography, such as grade banks. Existing earthwork features were mappedand their condition recorded. Areas affected by waterlogging in winter were mappedaccording to information provided by the landholders. Areas affected by secondarydryland salinity were similarly described and mapped.

Areas such as the arterial drainage lines are considered to be naturally saline (primarysalinity) as they were saline before land clearing for agriculture. Only areas ofsalinisation that has developed since clearing (secondary salinity) were mapped as partof this project.

Rock outcrops, where they were likely to have impacts on planned surface watermanagement features and affect soil depth or groundwater movement, were alsomapped. Some rock outcrops were also mapped opportunistically.

Anecdotal information on flood water behaviour was mapped based on informationfrom the landholders. All mapping was conducted using heads up “digitising directlyinto a GIS database”.




Each landholder authorised the use of information collected during the interview to beused in this study and presented in the individual reports. Appendix E contains thestandard consent form signed by each landholder and submitted to DCLM.

2.5 Development of Demonstration Site Surface WaterManagement Plan and Report

Based on the results of the literature review, the meeting with landholders within thecatchment and the inspection of the demonstration site and catchment, a surface watermanagement plan was developed for the demonstration site. This has beendocumented and is presented in a separate report, which is attached in Appendix A.

2.6 Development of Individual Surface Water ManagementPlans

During the inspections landholders’ surface water management actions were discussedand an agreed plan of management for those issues currently not being adequatelymanaged was designed. Surface water management earthworks were designed toaddress each threat or problem identified. They were given a priority rating basedboth on the priority given by the property owner and the technical priorities imposedon earthworks implementation. For example, a series of grade banks across a hillslope would require the uphill bank to be built first then the other banks downhill insequence. This protects the lower banks from being washed out by an intense rainfallevent.

The specifications for grade banks and the spacing between them were determinedusing best practice guidelines contained in Keen (2001) and Keen (1998). As nomeasured streamflow data were available for the study, the peak flow estimate for thedemonstration site catchment was based on the Australian Rainfall and Runoffmethodology for the Wheatbelt region (Pilgrim, 1987). This text includes empiricalequations for calculating peak flows and rainfall data that includes recordings from theDalwallinu recording site. These equations were derived from calibration carried outagainst actual stream data in the relevant regions.

The proposed earthworks layout and specifications were developed by identifying theslope and soil type contributing runoff to each proposed structure. Using the tableprovided by Keen (2001), the recommended maximum bank spacing was determined.In accordance with Keen’s recommendations, this spacing was reduced by 10% forhighly erodible soil types such as sands and also for heavy clay soils which canproduce large volumes of runoff. This methodology has proved reliable throughoutthe agricultural areas of Western Australia for many years.

Locations for surface water disposal into natural waterways were determined. Thesewaterways were chosen on the basis of their ability to contain expected flow volumes.This was assessed on the basis of their cross-sectional area, condition in terms oferosion and landholders’ descriptions of their behaviour in the 1999 flood event.

All plans developed were captured as a GIS dataset and supplied to DCLM.




Development of Individual Surface Water Management Plan Reports

Based on these plans individual landholders reports were compiled which:� Provide a brief context to the study;� Describe the landholders natural resources as they relate to surface water

management including;- The state of the current drainage features, including surface water control

features;

- Soil and landscape information in relation to its water shedding and flowinhibition potential; and

- Major hazards;

� Describe the surface water management plan developed, including;- Comment on any landholder planned surface water control features. This

includes the review of any existing farm plans or other documentedinformation provided by the landholder;

- Discussion of the recommended surface water control measures (bestsolutions within the catchment context). Each proposed surface watercontrol structure has been attributed with description, ID number, grade,channel width, bank height, cut depth, notes and priority ranking; and

- Estimation of likely costs.

� Provide justification for the surface water management plan developed.

All of the individual surface water management plan reports produced are attached inAppendix B.

Development of Catchment Scale Surface Water Management Plan and Report

The individual surface water management plans were then amalgamated into acatchment management plan. Based on the information generated in the individualsurface water management plans, generalisations have been drawn together andpatterns identified relating to surface water management within the study area. Thesegeneralisations are likely to be applicable across the Buntine-Marchagee NaturalDiversity Recovery Catchment.

Presentations on Study

Following from the submission of this report, a presentation will be given to therelevant DCLM staff outlining the key findings of the study.

In March or April 2003 there will also be a presentation of the key findings andrecommendations of the study to the Coorow community.




3. Statement of Current Surface WaterHydrology

In order to be able to logically present the surface water hydrology situation within thestudy area, it is essential that the location, geology, soils and surface and groundwaterhydrologies be presented. These are each discussed in the following sections.

3.1 LocationThe study area is centred approximately 40 kilometres south east of Coroow. Coroowis located 230 kilometres north north east of Perth (see Figure 3-1 and Figure 3-2) inwhat is known as the “north midlands” region of the agricultural area.

n Figure 3-1 General location diagram of study area

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3.2 Geology and LandformsBased on geological mapping by the Geological Survey of Western Australia (1980),there are three distinct types of landscape in the study area (Figure 3-3):

� A north-south oriented upland ridge which is located approximately in the centreof the study area, occupying 26% of the study area. It is characterised by soilslargely derived from in-situ weathering. They consist of clays, clay loams andloams and duplex sandy gravels. The thickness of the weathered material (orregolith) over basement varies between 5 metres to more than 20 metres. Parts ofthis zone are overlaid by aeolian (wind-transported) sandplain sands.

� The second landscape type is the ancient drainage zone, valley floor which Iispart of the arterial drainage system. This occupies 13% of the study area. Thisconsists of a complex mosaic of alluvial soils in the river channel, pans and lakes.On the surface they appear as red/brown loams, red/brown clays and grey clays.Often the clays are only a cap over coarser sediments. There are some lowgypsiferous dunes on the south-east margins of some of the salt lakes and someaeolean sandplain deposits overlying parts of this mainly sedimentary part of thelandscape.

� Finally there is the sandplain landscape. This occupies 61% of the study area. Itconsists of grey, white or more commonly, yellow quartz sand, often 5 metres ormore in depth overlying in-situ weathered loams, clay loams sandy clays andclays. Total depth to basement can be in excess of 40 metres (Buntine-Marchagee Recovery Catchment drilling logs). This landscape is characterisedby numerous small lakes or seeps sitting above a massive silcrete hardpan. Thishardpan was produced by cementation with silica near the surface of a past watertable as it fluctuated with the seasons.




� Figure 3-3 Landforms of the study area. (derived from GeologicalSurvey of Western Australia mapping).

3.3 SoilsFigure 3-4 illustrates the distribution of soils within the study area and Table 3-1 thearea and proportion of the study area, of each soil type.

The soil types present within the study area strongly reflect the landforms described inSection 3.2.

The duplex soils landform consists of a range of soil types including red/brown loamsred clay loam and red clay which are present at or close to the soil surface. There areareas where the sands have deposited on the surface and these surface soils aregenerally gravelly sand and shallow sand over gravel or yellow sandy loam soils.

The lake chain river landform also consists of a range of surface soils (alluvial riversoils) which vary spatial over small distances.




The sandplain landform consists almost entirely of the yellow sandplain and gravellysand and shallow sand over gravel soil types, with some areas of deep white/grey sandand yellow sandy loam.

� Figure 3-4 Soils of the Buntine-Marchagee Surface WaterManagement Planning Study Area.




� Table 3-1 Summary of area and percentage of study area of each ofthe standard soil descriptions.

Soil Type Area (hectares) Percentage of StudyArea

Deep White/Grey Sand 1580 3.3%Gravelly Sand and shallow Sand over Gravel 8400 17.7%

Grey Clay 230 0.5%Red Clay 3040 6.4%

Red Clay Loam 860 1.8%Red Brown Loam 4580 9.6%

Alluvial River Soils Complex 7370 15.5%Yellow Sandplain 16310 34.4%

Yellow Sandy Loam 3020 6.3%Unmapped (includes road reserves, crown

land etc.)2120 4.5%

3.4 Existing Hydrology3.4.1 Surface waterThe three landscape zones described in the geology section of this report (Section 3.2)are three very different zones in terms of surface water behaviour.

The central upland ridge forms a duplex soil landform. Surface water behaviour hereis characterised by relatively rapid runoff due to heavier soil types and slopes in theorder of 3% to 4%. Erosive runoff has been a problem for landholders in this part ofthe study area and most have surface water management earthworks in place mainlyfor erosion control.

High volumes of runoff from the steeper slopes often causes waterlogging on the flatsadjoining the main river system. Such waterlogging is costly to landholdersparticularly when it occurs in crops. Often, sub-clinical levels of waterlogging gounnoticed during the growing season but result in substantial yield reductions. Insome cases, surface water management earthworks to control waterlogging incropping paddocks can repay their entire capital cost through improved crop yield inthe first year after installation.

Surface water management earthworks can also be used to direct surface runoff andshallow surface seepage into storage dams. This strategy, as well as increasing freshwater resources, would offer a potentially valuable means of flood flow detention.Unfortunately, the landholders interviewed described a general lack of success infinding suitable sub-soil clays for dam building, even on the duplex soils landform.Many of these dams that have been established are reported to leak. This explains thelow number of dams observed in the study area.

The sandplain landform has a much lower density of natural surface drainage lines andmost of these are fed from shallow groundwater seepage. There is generally nooverland flow except where the sands have become non-wetting, water is concentratedby a road or runs on from an adjoining area of heavy soil. There are numerous smalllakes and seeps with water quality ranging from ‘near-rainwater’ fresh to ‘seawater’




salty. Most of the water bodies are fresh to brackish with a small number being verysaline.

The lake chain/river system, or zone of ancient drainage, rarely flows over its entirelength. Flood conditions are necessary for this to occur. The playa lakes act asevaporation basins for water that runs onto them from higher in the landscape.Although the surface soils within this system appear to be generally heavy textured,there is great variation within this zone. Rapid groundwater recharge by surface waterscan occur where the surface soils are alluvial sands.

3.4.2 GroundwaterWithin the study area groundwater characteristics are described for each of thelandforms types described in Section 3.2. These descriptions are a summary of waterlevels and salinities in bores reported by landholders and determined by opportunisticfield sampling (using a handheld salinity meter) during farm inspections.Groundwater quality information provided by DCLM was reviewed and wheredeemed pertinent incorporated into the following descriptions.

Duplex landscape zone.

Groundwater in the duplex soils landform zone ranges from 5 metres to 15 metres indepth and commonly sits at approximately 7 metres.

Salinity of this groundwater ranges from 182 msm-1 to 1850 msm-1 with most beingaround the 800 msm-1 level. This represents a range of suitability from domestic andrestricted irrigation use to being barely suitable for adult sheep and irrigation of onlythe most salt tolerant species (Hunt and Gilkes, 1992). The bore information collectedfrom the landholders indicates that the aquifer is in the weathered material (saprolite)close to basement. Hillside seeps are not evident in this landform zone. It appearsthat groundwater has relatively low piezometric pressure and/or unrestricted pathways.

Sandplain landscape zone.

In the sandplain zone groundwater behaviour is more complicated. Bores in this zonehave water levels ranging from 5 metres to 20 metres with most around the 10 to 15metre level in bores that are 20 to 25 metres deep. It is assumed that these bores aretapping into deep groundwater in the weathered saprolite beneath the sandplainoverburden.

It was found that deep groundwater salinities in the sandplain landscape zone rangefrom 250 msm-1 to 1800 msm-1 with most around 1000 msm-1.

Shallow perched water tables are common throughout the sandplain landscape zone.These often sit on a silcrete layer approximately 3 metres below the surface and have1 to 2 metres of aquifer depth (based on field inspection and information provided bylandholders.). This shallow aquifer discharges at localised depressions, seeps, soaksand small lakes (see Figure 3-5, Figure 3-6 and Figure 3-7). Silcrete layers weredetected at greater depths (8 metres) during recent drilling conducted for DCLM(Department of Conservation and Land Management, 2002) and it may be that the




depth and topography of the silcrete layer(s) has a significant influence on thegroundwater hydrology of the sandplain landscape zone.

� Figure 3-5 Typical sandplain soak (on Hodgson’s property).

� Figure 3-6 A small sandplain lake (on Hodgson’s property).




� Figure 3-7 Sandplain soak showing groundwater seepage (onStacey’s property).

It was noted during field inspections that many of these lakes and soaks have twotypes of reeds growing on their margins. There is a salt tolerant variety which hasstronger leaves and sharp spikes on the ends of them with a greyish foliage colour.The other variety is what some landholders described as “fresh water reeds” whichhave finer, greener leaves and don’t have as severe a spike. At many of the lake orsoak sites these reed types were segregated to opposite ends of the water body. The“fresh water” reeds were located mostly at the discharge side of the water body (whererelatively fresh water is seeping in). At many of these sites there was a measurableincrease in salinity from the “fresh reed” end to the “salty reed” end. Salinity of theseshallow surface waters ranged from 40 msm-1 to beyond the range of the measuringinstrument at 2000 msm-1. Most shallow groundwater water salinities measured orreported from landholders during the field inspection were around the 400msm-1 level.

Some of the lakes and soaks were distributed in linear patterns which suggests lines ofshallow groundwater movement (see Figure 3-8). This is supported by theobservation of increasing salinity in the interpreted direction of flow. It would bepossible to confirm this interpretation by installing transects of piezometers andobservation bores.

The low spatial density of surface drainage lines in the sandplain landscape zonesuggests that most drainage from this zone is predominantly via groundwater. Thismechanism may be providing more recharge per hectare of catchment to the deepaquifer of the lake chain/river system than does the duplex soils landform zone. Asdiscussed above, the surface drainage lines of the duplex soils landform zone deliversurface water to the river system where it generally sits in the lakes above the clay capand evaporates.




Currently available surface and bore data are not adequate to determine the veracity ofthe above hypothesis. It is not known what degree of connectivity exists between theshallow perched aquifer and the deep aquifer in the sandplain landscape zone. Thearea of sandplain landscape that contributes water to the river system may be differentfrom that suggested by the surface topographical catchment. There is a possibility thatthere is a groundwater divide near the central south of the sandplain landscape zone inthis study area. To the west of this divide groundwater may move in a north westerlydirection towards the headwaters of rejuvenated darling scarp creeks (Figure 3-8).

� Figure 3-8 Interpreted perched water table flow lines, within studyarea.




Lake chain/river landscape zone.

From surface appearance, this zone is interpreted to be the site of a palaeochannelfilled with palaeo-drainage sediments.

Due to the low energy status of the drainage over time, the valley has filled withsediments. Low slope streams tend to meander, and as the valley filled, strands ofvarious sediments were deposited heterogeneously across the valley floor. Thisprocess creates an extremely complex regolith in this landscape zone.

These sediments can vary from coarse river sands to dense watertight clays. Thesurface tends to consist largely of clays as they are the last particles to drop out ofsuspension. The clay “cap” on the lake chain/river system, although nothomogeneous, can support fresh water flows in times of high rainfall.

The groundwater piezometric surface within the zone is approximately 2.5 metresfrom the surface, (Department of Conservation and Land Management, 2002). Thefastest growing areas of secondary salinisation observed in this project are located onthe margins of this lake chain/river system. Due to the flatness of these areas and theproximity of the water table to the surface, it only takes a small rise in water table toaffect large areas of land.

As discussed above, palaeochannel sediments are characterised by sinuous patterns ofdeposition of clays, sands and gravels. It is through the sands and gravels thatgroundwater can move relatively unimpeded. The DCLM drilling did not intersect“typical” palaeochannel strata (DCLM, 2002). That is not, however, to say that apalaeochannel does not exist as it is reasonable that any palaeochannel that may existmay not have been intersected by the drilling.

At Toolibin Lake in the Great Southern area of Western Australia, extensive drillingfailed to locate a significant palaeochannel. This palaeochannel wasn’t located untilinterpreted information from airborne geophysical surveys became available (Pracilioet al, 1998 and George, 1998).

The importance of locating palaeochannels lies in their hydrological behaviour and itsimplications for groundwater management. They contain large volumes ofgroundwater that is potentially easily extracted. Because water moves relatively freelythrough these sediments, pumping effort can potentially produce a draw-down of thewater table over a relatively large area.




4. Best Practice Surface Water ManagementPlanning

The basis of best practice in surface water management planning is to determine themaximum magnitude of the runoff event that the designed works are intended tohandle and then design to this. It is not possible to design surface water managementearthworks that will never fail. The best practice approach selects a magnitude ofrunoff event which has a specific probability of recurring over time. For eventsbeyond the selected magnitude and probability we are prepared to accept failure of thesurface water management infrastructure and the cost of repairs.

Runoff and infiltration rates can be affected by agricultural activities and to someextent they can be managed by choosing appropriate agricultural methods. Such anapproach is sometimes proposed as an alternative to surface water managementearthworks. However, because these day-to-day farm management decisions aredetermined more by economics and seasonal conditions than by considerations ofsurface water management, such techniques have not been recommended on theirown, as best practice surface water management within this study. Used in addition tosurface water management earthworks such management techniques could assistsurface water management and would fit well into a formal EnvironmentalManagement System (EMS) under the International Standards Organisation standard14001 (ISO 14001).

In Western Australia the Department of Agriculture has published standards forsurface water management earthworks on agricultural land. These are CommonConservation Earthworks Used in Western Australia (Keen, 1998) and Field PocketBook of Conservation Earthworks, Formulae and Tables (Keen, 2001).

These publications outline the variables that determine the success or failure of surfacewater management earthworks structures. They set standards for addressing thesevariables to meet the requirements of the runoff event magnitude for which the designis being prepared, such as a 1 in 10 year storm event. These publications go furtherand suggest that a 1 in 10 year average recurrence is the minimum runoff eventcriterion.

Rainfall intensities used in design calculations were sourced from the ‘Intensity-Frequency-Duration Design Rainfall Program (Version 2.2 – May 1995)’ whichcalculates design rainfall in accordance with Australian Rainfall and Runoff (Pilgrim,1987). The Dalwallinu location was used from this program as this is the nearestlocation, within this publication, to the study area.

The concept of surface water management on a catchment scale conjures up images ofregional diversion channels, levees, drains or impoundment’s. In this study area,works of such scale are not necessary for surface water management. This is becausemost of the properties involved are large, in the order of 2000 to 3000 hectares, andthey mostly cover sufficient area to contain natural waterways suitable for disposal ofout-fall from surface water management earthworks. The guidelines for length ofearthworks determined by the Department of Agriculture also restrict the distance thatwater can be diverted (in the order of 1 kilometre) (Keen, 2001). In this study area,




these two factors have confined most planned surface water management works withinindividual property boundaries.

The only exception to this occurs in the north of the study area where a grade bank isproposed to cross a property boundary into a neighbouring property for disposal ofrunoff into a natural creek line. This proposal is subject to agreement between the twoproperty owners. A second disposal option involving a grassed waterway is providedin the event that agreement is not reached (see Section 6 for more details).

In this study area the following surface water management issues were identified andhave been addressed in this study:

� Waterlogging on flats and lower slopes;� Flooding on lower slopes;� Soil erosion on steeper slopes;� Poor water catchment into dams;� Transfer of large surface flows without causing erosion; and� Relatively fresh shallow seepage causing soil salinity.

Waterlogging on flats and lower slopes was addressed by designing grade banks withspacing appropriate for the soil type and gradient of the slope. Grade and crosssectional specifications provided in Keen (2001) were adhered to. Disposal of waterfrom these grade banks was directed to natural waterways via level sill outlets whichspread the water evenly and minimise the risk of erosion.

Flooding on lower slopes was addressed both on the flats and on the slopes abovethem by designing grade banks with spacing appropriate for the soil type and gradientof the slope. Grade and cross sectional specifications provided in Keen (2001) wereadhered to. Disposal of water from these grade banks was directed to naturalwaterways via level sill outlets which spread the water evenly and minimise the risk oferosion. Some of the grade banks on the lower slope are designed to act as low leveesto limit the spread of any flooding event less than or equal to the 1 in 10 year event.

Soil erosion on steeper slopes was addressed in the same manner as the lower slopestaking into account the requirement for closer bank spacing on steeper slopes andheavier soil types and adjusting this according to the guidelines in Keen (2001).

Poor water catchment into dams was addressed (provided the dam did not have ahistory of leaking) by proposing grade banks to intercept surface water that wasflowing past the dam’s natural catchment and directing it into the dam. The proposedearthworks also addressed the disposal of overflow from the dam in a safe andpractical manner. These were designed according to the guidelines in Keen (2001).

Transfer of large surface flows without causing erosion was addressed by designingflat bottomed grassed waterways capable of handling the expected flow volumes.Design flow volume was calculated using the ‘Intensity-Frequency-Duration DesignRainfall Program (Version 2.2 – May 1995)’ which calculates design rainfall inaccordance with Australian Rainfall and Runoff (Pilgrim, 1987). Using formulaeprovided in Keen (2001), the necessary depth, width and designed freeboard of thewaterway were calculated.




Disposal of surface water into natural waterways was recommended and thesewaterways were chosen on the basis of their ability to contain expected flow volumes.This was assessed on the basis of their cross-sectional area, condition in terms oferosion and landholders’ descriptions of their behaviour in the 1999 flood event.

Relatively fresh shallow seepage causing soil salinity was addressed by proposingfirstly that the landholder implement a spring/summer cropping program on the area touse the fresh seepage water, hopefully profitably. This was suggested as it was theleast capital cost to the landholder. It was also proposed that seepage interceptorbanks be installed across the slope to provide some control which is independent ofday to day farm management decisions. These were designed according to theguidelines in Keen (2001).

Keen (1998) provides details of the design guidelines and typical drawings for eachtype of structure recommended in this report. These details have not been reproducedin this report and the reader is referred to Keen (1998) for further design information.Useful information and Best Management Practices for grade banks and waterwaysmay be found attached to the Moore Catchment Groups series of Local Action Planswithin the Upper Moore River Catchment (Moore Catchment Group, 2001).

It has also been noted that in general, the most effective economic incentive forlandholders to undertake surface water management is the increased profit generatedby increased yield of crops and pastures where waterlogging has been reduced(McFarlane et a.l, 1992).




5. Landholder ParticipationIndividual landholders within the study area were contacted to arrange an inspectionof their land within the study area. DCLM identified 27 landholders within the studyarea, of which, three were not interested in participating in the study and inspectionswere not made of their land.

The remaining 24 landholders within the study area were generally very keen tofacilitate the transfer of knowledge required to develop the Surface WaterManagement Plans (SWMPs). Details of the information collected, issues raised andplans developed are provided in the individual SWMP’s in Appendix B. A summaryof this dialogue with individual landholders is provided below:

� Most landholders did not perceive strong links between surface watermanagement and salinity control on their property;

� When considering earthworks planning for salinity control most landholders didnot distinguish between surface and ground water;

� Many of the landholders, particularly those on the sandplain areas were veryinterested to learn more about groundwater and its movement in the landscape;

� Most landholders were very knowledgeable on details such as depths of bores,water quality and water levels in bores. Many of them provided the informationfrom memory;

� All landholders interviewed were very cooperative. They perceived this study asa first step towards doing something about salinisation of water supplies and land,within the study area; and

� In most landholders’ minds, salinity was clearly the most importantenvironmental threat to their enterprise.




6. Catchment-scale Surface WaterManagement Planning

A clear majority of the proposed surface water management earthworks are located inthe duplex soils landform zone. Most of the surface water management issues arelocated there and earthworks are the appropriate means of addressing issues on thesesoil types.

Apart from the demonstration site, only one property’s surface water managementplan proposed moving surface water across a boundary, conditional on agreementbetween the neighbours. The landholders involved here are John Stacey and PhillipStone. John Stacey’s surface water management plan contains an alternative strategyfor disposal of the water in the event that the cross-boundary disposal option does notproceed. These plans are further detailed in the landholders individual SWMP’s (inAppendix B).

Although no catchment scale surface water management works are proposed for thestudy area, the sum of the individual proposals is likely to have a significant benefit interms of reduced recharge on the duplex soils landscape zone. Coles and Mahtab(2000) reported modelling that showed a significant reduction in the incidence ofwaterlogging and inundation through the implementation of catchment-wide surfacewater management earthworks.

Furthermore the investigation of the study area revealed the different mechanisms ofsurface water migration to the main river system observed on the two distinctlydifferent landscape zones (that is, by surface water movement in the duplex soilslandform and by groundwater movement in the sandplain landform). It also revealedknowledge gaps in how much is known about groundwater movement and thecharacteristics of the regolith that control it. The insights gained from this study willbe valuable in determining future strategies for protecting the biodiversity values ofthis study area into the future.

Clearly salinity and groundwater issues are high priorities for the local community(see Section 5). This study has focussed attention onto the characteristics ofgroundwater movement in the two upland landscape zones. This will facilitateimproved management decisions with respect to managing both surface andgroundwater.

Most of the existing and proposed surface management earthworks are located on theduplex soils landscape zone. This is because this zone has the steepest slopes andrelatively heavy soil types, a combination of characteristics which generates relativelylarge volumes of runoff per unit area. As can be seen in Figure 6-1 and Figure 6-2,the duplex soils landform has the greatest density of both existing and proposedsurface water management earthworks.




Within this zone, as elsewhere in the study area, existing surface water managementstrategies varied between landholders. They ranged from minimal to comprehensive,with most being adequate and some adequate in design if not in maintenance.

The adoption of minimum tillage cropping practices by most landholders of the studyarea has resulted in the landscape generating significantly less runoff per unit area.This is the main reason for surface water management infrastructure either not beingmaintained, or in some cases removed or “thinned out”.

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7. Conclusions and RecommendationsThe majority of proposed surface water management earthworks are located in theduplex soils landform zone. This comprises only 26% of the study area, with the lakechain/river landform and the sandplain landform occupying 13 and 61% respectively.

The fastest growing areas of secondary salinisation observed in the project area arelocated on the margins of the lake chain/river system. Due to the flatness of theseareas and the proximity of the water table to the surface, it only takes a small rise inwater table to affect large areas of land.

Using surface water management earthworks it is possible to achieve in the order of10% reduction in recharge and runoff (Coles and Mahtab, 2000), on 26% of the studyarea. However, current lack of understanding of groundwater movement in thesandplain landscape zone is limiting ability to impact on 61% of the area.

Understanding the hydrology of the sandplain and its underlying regolith as well asthe hydrology of the river valley holds the key to protecting the biodiversity values ofthis study area from the threat of salinity.

In order to further progress the understanding of how to protect biodiversity valueswithin the catchment from increased salinity the following recommendations aremade:

1) Surface water management controls described in the individual SWMPs(Appendix B) are implemented, particularly for those properties lying within theduplex landform area; and

2) Further investigations be conducted to gain better knowledge of the groundwatersystems throughout the catchment and particularly in the lake chain/river andsandplain landforms.




8. AcknowledgementsThe success of this study has been due to the review, advice and direction by manygovernment agency staff. Particular thanks goes to Jodie Watts, Recovery CatchmentOfficer, Department of Conservation and Land Management, for overseeing the studyas a whole and ensuring that the requirements of the study were met to a suitablestandard. The efforts of Peter Whale, Kelly Gillen and Anthony Desmond are alsoacknowledged.

Without the time and knowledge of the landholders within the study area, this studycould not have been conducted. We would like to thank the following landholderswho gave their valuable time and knowledge:

� Ivan and Noelene Bean;� Geophrey Bell;� Rod and Shelley Birch;� Lindsay and Robyn Cousins;� Frank and Jeanie Crago;� Douglas James Dobson;� John and Alison Doley;� Steve and Moira Girando;� James Hodgson;� Ian and Helen Hunt;� Trevor and Jill Just;� Mark Mailey;� Lionel Morton;� Vern and Jan Muller;� Gerard Noble;� Michael and Julia O’Callaghan;� John O’Neill;� Mark Pearse;� Anthony Shields;� Beth and Sam Southcott;� John and Robyn Stacey;� Jack and Kathy Stone;� Phil and Polly Stone; and� Peter and Yanti Vanzetti.




9. ReferencesColes, N.A. and Mahtab, Ali S. 2000. Implications for Surface Water Management onRecharge and Catchment Water Balance. Hydro 2000 : 3rd International Hydrologyand Water Resources Symposium of the Institution of Engineers, Australia, 20-23November 2000, Sheraton Perth Hotel, Perth, Western Australia proceedings.Institution of Engineers, Australia, 2000. Barton, A.C.T. Volume 1, p.317-322

Department of Conservation and Land Management. 2002. Buntine-MarchageeRecovery Catchment drilling logs. Internal DCLM documentation.

Geological Survey of Western Australia. 1980. Moora 1 :250000 Geological Sheet,SHJ 50-10 of the International Series. With accompanying explanatory notes: Carter,J.D. and Lipple, S.L..1980. Explanatory Notes On The Moora Geological Sheet.Geological Survey of Western Australia.

George, R. 1998. The National Airborne Geophysics Project. Toolibin WesternAustralia Evaluation of airborne geophysics for catchment management. Report toAgriculture Fisheries and Forestry Australia and National Dryland Salinity Program.

Hunt and Gilkes, 1992. Farm Monitoring Handbook. The University of WesternAustralia, Nedlands.

Keen, M.G., 1998. Common Conservation Earthworks Used in Western Australia.Department of Agriculture, Western Australia, Technical Report 185

Keen, M.G., 2001. Field Pocket Book of Conservation Earthworks, Formulae andTables. Department of Agriculture, Western Australia, Bulletin 4534

McFarlane, D.J., Wheaton, G.A., Negus, T.R. and Wallace, J.F., 1992. Effects ofwaterlogging on crop and pasture production in the Upper Great Southern, WesternAustralia. West. Aust. Dept. Agric. Tech. Bull 86.

Moore Catchment Group, 2001. Upper North Moore River Local Action Plan. Reportby the Moore Catchment Group as part of the project “Improving Surface WaterManagement in the Upper Moore River Catchment”. February 2001.

Pilgrim, D.H., editor, 1987. Australian rainfall and runoff : a guide to flood estimationInstitution of Engineers, Australia, Barton, A.C.T.

Sinclair Knight Merz, 2001. Impact Assessment and Management of Drainage WaterDischarge to Lakes in the Moore River Catchment, W.A. Report to the Water andRivers Commission.

Pracilio, G., Street, G.J. Nallan Chakravatula, P., Angeloni, J.R., Sattel, D., Owers, M.and Lane, R., 1998. 3. Lake Toolibin SALTMAP Survey Interpretation report - August1998. World Geoscience Corporation for National Dryland Salinity Program.

Stoneman, T.C., 1990a. An Introduction to the Soils of the Moora Advisory District.Department of Agriculture, Western Australia, Bulletin 4182.




Stoneman, T.C., 1990b. An Introduction to the Soils of the Three Springs AdvisoryDistrict. Department of Agriculture, Western Australia, Bulletin 4182.



WV02367:R31SXAPAF_CATCHMENTREPORT.DOC Rev 1

Appendix A Demonstration Site Report




Appendix B Individual Landholder SWMPs

Within this section the following individual landholder surface water managementplans are presented, in order:

q Ivan and Noelene Bean – Property Surface Water Management Plan Report;q Geophrey Bell – Property Surface Water Management Plan Report;q Rod and Shelley Birch – Property Surface Water Management Plan Report;q Lindsay and Robyn Cousins – Property Surface Water Management Plan Report;q Frank and Jeanie Crago – Property Surface Water Management Plan Report;q Douglas James Dobson – Property Surface Water Management Plan Report;q John and Alison Doley – Property Surface Water Management Plan Report;q Steve and Moira Girando – Property Surface Water Management Plan Report;q James Hodgson – Property Surface Water Management Plan Report;q Ian and Helen Hunt – Property Surface Water Management Plan Report;q Trevor and Jill Just – Property Surface Water Management Plan Report;q Mark Mailey – Property Surface Water Management Plan Report;q Lionel Morton – Property Surface Water Management Plan Report;q Vern and Jan Muller – Property Surface Water Management Plan Report;q Gerard Noble – Property Surface Water Management Plan Report;q Michael and Julia O’Callaghan – Property Surface Water Management Plan

Report;q John O’Neill – Property Surface Water Management Plan Report;q Mark Pearse – Property Surface Water Management Plan Report;q Anthony Shields – Property Surface Water Management Plan Report;q Beth and Sam Southcott – Property Surface Water Management Plan Report;q John and Robyn Stacey – Property Surface Water Management Plan Report;q Jack and Kathy Stone – Property Surface Water Management Plan Report;q Phil and Polly Stone – Property Surface Water Management Plan Report; andq Peter and Yanti Vanzetti – Property Surface Water Management Plan Report.




Appendix C Soils Descriptions

C.1 SoilsApproximately 75% of the study area had soils mapped by David Kessell of MooraFarm Consultancy approximately five years ago. This information was digitised fromproperty owners’ interpretations of the soil types on their farms after attending a soiltype assessment field day with the then Catchment Co-ordinator, Sue Kricki, in 1997-1998. Corrections to the initial property owners’ mapping were completed withindividual property owners and with the attendees at a catchment group meeting. Thismapping contained some 25 soil types.

Many of Kessell’s 25 soil types are separated by very minor differences. These werecategorised into the eight standard soil descriptions to create a simple, meaningful setof soil types and description for the study area.

The eight standard soil descriptions were developed from field inspections in the studyarea, using “Soils of the Moora Advisory District” Stoneman, (1990a) and “Soils ofthe Three Springs Advisory District” Stoneman, (1990b) as references. Stoneman’sreports contain detailed profile descriptions and soil pit photographs, which have beenreproduced within this report.

A ninth description was applied to the drainage channel soil complex.

The soils of the properties within the study area, not covered by Kessell’s mapping,were mapped as part of this study. Soil boundaries were identified by the landholdersusing the nine standard soil descriptions with the aerial photograph used as the basemap.

Each of the nine standard soil descriptions are described in Section C.1.1 andphotographs of typical soil profiles from Stoneman (1990a and 1990b) of nine of thesoil types are shown in Figure C-1.




(a) (b) (c)

(d) (e) (f)

(g) (h)

n Figure C-1 Plates illustrating typical soil profiles of soil types withinthe catchment: (a) Deep white/grey sand; (b) Yellow sandplain; (c)Gravelly sand and Shallow sand over gravel; (d) Yellow sandy loam;(e) Red/brown loam; (f) Red clay; (g) Red clay loam, and (h) GreyClay from Stoneman, (1990a and 1990b).




C.1.1 Soil Profile Descriptions

Deep white/grey sand.The profile is a deep white/grey sand to one metre or more in depth over a yellowclayey sand containing lateritic ironstone nodules at about 1.5 metres.

Locally known as Banksia sand, this soil type occurs mainly in the western parts of thestudy area. The study area is located south east of Coorow. Within the study area thesoil type occurs as isolated areas within the Yellow Sandplain soil type. This soil isslightly acidic throughout its profile. It tends to be non-wetting and susceptible towind erosion. Where it has been cleared, this soil type has often been retired fromcultivation due to low productivity and wind erosion risk.

Surface water behaviour:Non-wetting characteristics cause some runoff with summer thunderstorms or firstwinter rains. Once this soil type has “wetted up”, infiltration is rapid. Can beconsidered a groundwater recharge zone.

Gravelly Sand and Shallow Sand over GravelThe profile is grey sand or gravelly sand over mottled sandy clay at approximately 40centimetres with many ironstone nodules. It is slightly acid throughout the profile.Within the study area, this soil occurs on hill crests and upper slopes and frequently asisolated areas within the Yellow Sandplain soil type. The native vegetation consists oflow mallee (Eucalyptus spp.) and sandplain heath.

Surface water behaviour:Susceptible to waterlogging in areas of low slope and gully and sheet erosion can bean issue once the upper profile becomes saturated. Its occurrence as small areasamongst sandplain makes this difficult to manage. Larger areas can be managed withcontour earthworks and can provide opportunities for surface water harvesting.

Grey ClayThe profile is Grey/Brown throughout consisting of less than 10 centimetres of sandover sandy clay. The soil is slightly acidic at the surface but becomes alkaline belowabout 30 centimetres. This soil type mainly occurs on the valley floor within and onthe margins of the main drainage lines. It comprises one of the soils of the AlluvialRiver Soils Complex. The native vegetation is salmon gum (Eucalyptussalmonophloia).

Surface water behaviour:This soil has the capacity to generate a high rate of runoff due to the proximity of clayto the surface and especially where it has been degraded by cultivation. It is oftensubject to waterlogging and salinity due to its location in the landscape.

Red ClayThe profile consists of a reddish brown sandy loam to about 10 centimetres over darkred sandy clay grading to a heavy red clay by 50 centimetres. In many paddocks thathave been regularly cultivated prior to the era of minimum tillage cropping, the clay




has been incorporated into the surface layer giving it a heavier texture than it had atthe time of clearing. Within the study area this soil type occurs in association with theRed/Brown Loam and usually upslope of it. The native vegetation is York Gum(Eucalyptus loxophleba).

Surface water behaviour:This soil has the capacity to generate a high rate of runoff due to the proximity of clayto the surface and especially where it has been degraded by cultivation. Erosion oflighter soil types downslope can be caused by runoff from this soil type.Waterlogging of the loamy surface layer can be a problem on flat areas. The potentialfor water harvesting is good and the subsoil clay is generally suited to damconstruction provided saline watertables are more than 2 metres below the excavationdepth.

Red Clay LoamThe profile is red throughout consisting of sandy loam to 20 centimetres where itbecomes sandy clay. The sandy clay gives way to heavy clay at about 75 centimetres.The top 50 centimetres is neutral in reaction, becoming alkaline below 50 centimetres.This soil type occurs in association with the Red Clay and the Red/Brown Loam in thelower parts of the landscape. The native vegetation is York gum (Eucalyptusloxophleba).

Surface water behaviour:This soil has the capacity to generate a high rate of runoff due to the proximity of clayto the surface and especially where it has been degraded by cultivation. Erosion oflighter soil types downslope can be caused by runoff from this soil type.Waterlogging of the loamy surface layer can be a problem on flat areas. The potentialfor water harvesting is good and the subsoil clay is generally suited to damconstruction provided saline watertables are more than 2 metres below the excavationdepth.

Red/Brown LoamThe profile consists of brown or reddish brown sandy loam to loam grading quiteabruptly to a sandy clay by 30 centimetres and a medium clay by 45 centimetres.Calcareous nodules occur in the clay. The soil is acidic in the upper layers, becomingalkaline at the level of calcareous clay. This soil type occurs on broad flat valleyfloors, flood plains and adjoining terraces. Within the study area it is mainly found asdescribed which is at the interface between the central north-south running ridge andthe main drainage line. The native vegetation is York gum (Eucalyptus loxophleba).

Surface water behaviour:Sheet and rill erosion of the lighter surface profile can occur on sloping ground andwaterlogging where there is low slope. This soil type has a strong capacity to generaterunoff. There is potential for water harvesting on this soil type, however, dam sitesmust be carefully selected to avoid saline watertables.

Alluvial River Soils ComplexThis is a complex mosaic of mainly sedimentary soils in the river channel, pans andlakes. On the surface they appear as red/brown loams, red/brown clays and greyclays. Often the clays are only a cap over coarser sediments. There are some low




gypsiferous dunes on the southeast margins of some of the salt lakes and some aeoleansandplain deposits overlying parts of this mainly sedimentary part of the landscape.

Yellow SandplainDeep pale yellow sand, becoming brighter yellow with increasing depth. Sand is oftenmore than 2 metres deep. In parts, clayey sand can occur at depths of 1 metre or more.

This soil type occurs mainly in the western parts of the study area. Within the studyarea the soil type occurs mainly as a band on the southern and western side of themain drainage line. It comprises a gently undulating landform on the valley floor andsouthern and western slopes. The soil is acidic throughout its profile. The nativevegetation consists of Banksia and Christmas tree (Nuytsia floribunda) changing toCasuarina spp., Acacia spp. and Hakea spp. on the deeper sands.

Surface water behaviour:Rainfall infiltration is rapid. Numerous soaks, mostly perennial, above a silcrete layerindicate a perched watertable of mostly low salinity. This aquifer is the main sourceof stock water and domestic water where these soils predominate.

Yellow Sandy LoamThe profile consists of loamy sand at the surface to clayey sand at depth. Like theYellow Sandplain, this soil is slightly acid in reaction throughout. It occurs in thesame landscape positions as the Yellow Sandplain. The native vegetation is sandplainheath. The subsoil can become compacted over time to the extent that crop growth isaffected. This can be corrected by deep ripping. This soil type can be susceptible towind erosion under poor management.

Surface water behaviour:Water erosion can occur on this soil type, mainly as a consequence of intense rainfall,and particularly when the soil has been cultivated. This can be managed with contourearthworks. Surface water can be harvested using roaded catchments, howeverfinding suitable subsoil clay for dam building can be difficult.




Appendix D Project Information Provided toLandholders

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Date: 23, September, 2002

Buntine-Marchagee Natural Diversity Recovery Catchment.

General Information

The Buntine-Marchagee catchment is the fifth natural diversity recovery catchment declared under thesalinity strategy. Other recovery catchments are the Lake Warden complex near Esperance, Toolibin Lakeeast of Narrogin, Muir-Unicup complex between Manjimup and Mt Barker and the Lake Bryde systemsouth-east of Lake Grace.

Natural diversity recovery catchments are identified in the State Salinity Strategy because they have highnatural diversity at risk from rising water tables and salinity. Recovery catchments aim to conserve naturaldiversity by implementing well-planned work with local communities and surrounding landowners.

A 140,000ha area in the northern agricultural zone between Dalwallinu and Coorow has become a recoverycatchment for natural diversity under the State Salinity Strategy and is known as the Buntine – MarchageeNatural Diversity Recovery Catchment.

This particular catchment is different to other recovery catchments because although it is threatened by risingwater tables, it has not yet reached a critical stage. It is also a naturally saline braided channel, a wetlandform typical of the Eastern Wheatbelt.

The Department of Conservation and Land Management (DCLM) is co-ordinating preparation of a recoveryplan for the catchment. This will involve close consultation with local land conservation district committeesand catchment groups through a steering committee.

DCLM have already established several biological survey sites across the catchment as part of its extensivesurvey work under the Salinity Strategy. In addition a steering committee has been formed and has metseveral times to provide direction to the activities undertaken in the recovery catchment.

Part of the steering committee's initial requirements for the recovery catchment project was to gain a betterunderstanding of the hydrological situation within the catchment. As part of this a series of Piezometers andObservation bores have been installed across the catchment and a contract was called for a Surface WaterManagement Planning Project.

Surface Water Management Planning Project

In September 2002 DCLM appointed Sinclair Knight Merz to produce a Surface Water Management Planand accompanying report for a sub-catchment within the Buntine-Marchagee Natural Diversity RecoveryCatchment.

The plan will provide information and analysis on the surface water control options for a section of theBuntine-Marchagee Natural Diversity Recovery Catchment. This data will be used to develop a surfacewater management strategy for the Recovery Catchment and assist in planning on-ground works to reducethe impact of erosion, waterlogging and flooding events on wetlands.

Operations will be undertaken within the specified project area, which is estimated to be approximately44,000 hectares.

The contract is expected to take approximately eight weeks, to be completed during November 2002.

Date: 24 March, 2003Project No: WV02367

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During the project Sinclair Knight Merz will consult with all landholders within the project area and inconjunction with the landholder, develop surface water management plans for individual properties. Thesewill be provided to the landholders, by DCLM, at the end of the project.

Expected Project Benefits

It is expected the surface water management plan will:q Help determine the options available to alleviate the impact of surface water movement on biodiversity

values;

q Help raise community awareness and understanding of surface water management options and issues;

q Provide landholders with a farm plan detailing current surface water management measures andrecommended measures;

q Accelerate the implementation of on-ground works needed to control surface water;

q Allow the steering committee and management team to make better investment decisions whenselecting the most effective salinity management treatments to apply in and around the catchment.

Project Objectives:

To prepare a Surface Water Management Plan to determine actions required to control surface watermovement;

To assist the Recovery Catchment Steering Committee in understanding the options for surface watercontrol.




Appendix E Landholder Authorisation to UseInformation Collected Proforma Sheet

Sinclair Knight Merz Pty Limited

ACN 001 024 095

ABN 37 001 024 095

7th Floor, Durack Centre

263 Adelaide Terrace

PO Box H615

Perth WA

Australia 6001

Telephone: +61 8 9268 4400

Facsimile: +61 8 9268 4444

Offices across Australia, New Zealand, South East Asia, The Pacific, The Americas and Europe

Department of Conservation and Land Management 24 March, 2003193 Marine TerraceGERALDTON WA 6530

L01paf_Landhauthority.DocWV02367

Attention: Jodie Watts, Recovery Catchment Officer

Dear Jodie,

Authorisation To Use Information Collected

A representative of Sinclair Knight Merz, who is working for CALM on a project titled ‘Theprovision of a Surface Water Management Plan for the Buntine-Marchagee Natural DiversityRecovery Catchment’, has recently interviewed me.

During this interview I was provided with a description of the project objectives, processes andoutcomes and I provided a range of information about my property including, but not limited to, thefollowing:q Surface water control works in place;

q Surface water control works planned;

q Information relating to historic surface water events (e.g. flooding events) and the success, orotherwise, of the existing surface water control works;

q General information regarding farm and paddock management systems (for example, farmaccess); and

q Information on soil types and distributions across the property.

I hereby give my permission for the information collected by the Sinclair Knight Merzrepresentative relating to my property to be used and presented in a catchment report.

Yours sincerely

Signature:

Name: Date:

Department of Conservation and Land ManagementAUTHORISATION TO USE INFORMATION COLLECTED24 March, 2003

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Landholder Details:

Landholder Name:

Property Name:

Property Location:

Phone Number:

Fax:

Email:

Radio Channel:

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