Guideline for the Determination of Wetland Buffer Requirements

Guideline for the Determinationof Wetland Buffer Requirements

for public commentDecember 2005

Prepared for the Department for Planning and Infrastructure

on behalf of the Western Australian Planning Commission

by Essential Environmental Services

Published by

Albert Facey House469 Wellington StreetPerth Western Australia 6000

Guideline for the Determination of Wetland Buffer Requirementsii

© State of Western Australia

Published by theWestern Australian Planning CommissionAlbert Facey House469 Wellington StreetPerth Western Australia 6000

Published December 2005

ISBN 0 7309 9535 6

internet: http://www.wapc.wa.gov.auemail: [email protected]

tel: 08 9264 7777fax: 08 9264 7566TTY: 08 9264 7535infoline: 1800 626 477

Copies of this document are available in alternative formats onapplication to the disability services coordinator.

Disclaimer

This document has been published by the WesternAustralian Planning Commission. Any representation,statement, opinion or advice expressed or implied in thispublication is made in good faith and on the basis thatthe government, its employees and agents are not liablefor any damage or loss whatsoever which may occur asa result of action taken or not taken, as the case may bein respect of any representation, statement, opinion oradvice referred to herein. Professional advice should beobtained before applying the information contained inthis document to particular circumstances.

Guideline for the Determination of Wetland Buffer Requirements iii

Acknowledgment

This Guideline has been formulated with the aid of the Wetland Buffers Working Group,chaired by the Department for Planning and Infrastructure (DPI), which provided directionand comments on the format and content of the document. This work has been overseen bythe Wetlands Coordinating Committee.

The technical basis for the Guideline was established previously through work undertaken byWelker Environmental Consultancy in the DPI commissioned study Buffering betweenwetlands and other land uses. This study resulted in two unpublished reports: Study intoBuffering Between Wetlands and Other Land Uses: A Management Framework for WetlandBuffering (2002) and Buffering Between Wetlands and Other Land Uses: A Guideline for theDetermination of Wetland Buffering Requirements (2003). Text from these reports has beenused directly in large parts of this guideline, where explanation of terms and concepts isprovided.

Essential Environmental Services acknowledges the significant work of Welker EnvironmentalConsultancy in defining the concepts of buffers, wetland function area, separation distanceand separation requirements, including supporting information, diagrams and tables. Thisinformation has been used directly to formulate the approach outlined in this Guideline.Essential Environmental Services claims no responsibility for the technical basis of theapproach.

Guideline for the Determination of Wetland Buffer Requirementsiv

Guideline for the Determination of Wetland Buffer Requirements v

Contents

Introduction 1The concept of wetland buffers 1

Process for determination of wetland buffer 3Step 1 Acknowledge existence of wetland 3Step 2 Identify wetland attributes, wetland

management category and establish management objective 3Step 3 Define wetland function area 6Step 4 Identify threatening processes 6Step 5 Identify role of separation 6Step 6 Establish separation requirement 7Step 7 Apply separation requirement to proposal

and assess ability of separation to achieve management objective 7

Using the Guideline 9

Wetland buffer definition summary sheet 11

Application note 1: Acknowledge existence of wetland 121.1 Step 1 121.2 Definition of wetlands 12

Application note 2: Identify wetland attributes, wetland management category and establish management objective 14

2.1 Wetland values, functions and attributes 142.2 Wetland management categories 152.3 Step 2 16

2.3.1 Determination of management category and objective 162.3.2 Identification of critical wetland attributes 16

Application note 3: Define wetland function area 253.1 Step 3 26

Application note 4: Identify threatening processes 294.1 Threats to wetlands 29

4.1.1 Alterations to the water regime 294.1.2 Habitat modification 304.1.3 Inappropriate recreational use 304.1.4 Water quality 31

4.2 Environmental risk of various land uses 324.2.1 Rural land uses 324.2.2 Urban land uses 334.2.3 Other land uses 33

4.3 Step 4 33

Guideline for the Determination of Wetland Buffer Requirementsvi

Application note 5: Identify role of separation 355.1 Separation 35

5.1.1 Separation distance and separation area 365.1.2 Physical barriers 37

5.2 Separation requirement 385.3 Step 5 38

Application note 6: Establish separation requirement 406.1 Category C wetlands 406.2 Category R wetlands 416.3 Category M wetlands 426.4 Step 6 43

Application note 7: Apply separation requirement to proposal and assess ability of separation to achieve management objective 45

7.1 Step 7 457.2 Separation measures are achievable 457.3 Separation measures are unachievable 45

7.3.1 C category wetlands 467.3.2 R and M category wetlands 47

7.4 Establishing an alternative separation requirement 477.5 Does the alternative separation

meet the wetland’s management objective? 477.6 Making a case for an alternative separation requirement 48

AppendicesAppendix 1: Resource documents 50Appendix 2: Definitions 53Appendix 3: Example of application of the guideline - Lake Yangebup 56Appendix 4: Example of application of the guideline - South Lake 64Appendix 5: Example of application of the guideline - Stillwater Gardens Lake 70

FiguresFigure 1: Generlised wetland buffering concept 2Figure 2: Proposed process for determination of wetland buffer requirements 4Figure 3: Linking wetlands 36Figure 4: Separation distance not able to be achieved 46Figure 5: Yangebup Lake 56Figure 6: South Lake 64Figure 7: Stillwater Gardens Lake 70

TablesTable 1: Wetland management category objectives 5Table 2: Recommended format for completing steps 3 to 5 9Table 3: Wetland types (after Semeniuk, 1987) 12Table 4: Relative importance of wetland

attributes to achievement of management aims 19Table 5: Defining the wetland function area for each attribute 27

Guideline for the Determination of Wetland Buffer Requirements vii

Table 6: Summary of lands uses and associated threats 34Table 7: Role of separation to address threatening processes 39Table 8: Category C wetlands: Separation and management 41Table 9: Category R wetlands: Separation and management 42Table 10: Category M wetlands: Separation and management 43Table 11: Wetland management categories,

objectives and management priorities 48Table 12: Requirements to support significant attributes of Yangebup Lake 59Table 13: Requirements to support significant attributes of South Lake 66Table 14: Requirements to support significant

attributes of Stillwater Gardens Lake 72

Guideline for the Determination of Wetland Buffer Requirementsviii

Guideline for the Determination of Wetland Buffer Requirements 1

Introduction

This guideline has been developed to assistlandowners, developers, planners andarchitects to identify an appropriate bufferbetween wetlands and land uses that willenhance or maintain the significantattributes and values of the wetland.

It should be used where a change in landuse or development is proposed in theimmediate vicinity of a wetland (ie within alot containing a wetland or adjacent to awetland) where the future use ordevelopment is likely to conflict with theestablished wetland management objective.This may include urban, some publicpurposes, intensive rural, commercial orindustrial uses and development.

The appropriate separation distance shouldbe identified at an early stage in theplanning process so that the proposed planachieves an acceptable environmentaloutcome, in the context of planning forsustainability.

This guideline recognises that the planningprocess must consider other relevantfactors, together with environmental factors,in decision-making. Importantly, planning isguided by sustainability principles, asestablished in the Western Australian StateSustainability Strategy, 2003, that guidestrategic actions to meet the ‘needs ofcurrent and future generations through theintegration of environmental protection,social advancement and economicprosperity’.

These guidelines do not apply wherelandowners are continuing existingactivities. However, the principles andapproach are supported to establish buffersfrom existing activities to improve theenvironmental health and conservation

status of a wetland, consistent with itsidentified management objective.

Buffering of a wetland is recognised asessential for the achievement andmaintenance of the wetland’s managementobjective. However, buffering should beconsidered as only one component of anintegrated approach to wetland protectionand management. Buffering is proposed asa tool to be employed where separation isappropriate and able to achieve the desiredwetland outcomes.

The role that catchment management playsin dealing with wetland issues such aspollution, particularly groundwater pollution,must also be recognised. Groundwaterpollution and its impact on wetlands, waterregime issues, the terrestrial habitatrequirements of many fauna species thatinhabit wetlands and the management ofmosquitoes and midges extend beyond theinfluence of wetland buffering. Theseaspects need to be considered as landplanning and management issues in theirown right and therefore are beyond thescope of this guideline.

The guideline is structured in seven stagesto establish an appropriate buffer betweenwetlands and existing or proposeddevelopment.

Additional information is contained inapplication notes, which cover theindividual stages of the process and helpthe user complete each step. Guidelineapplication examples, a list of resourcedocuments and a glossary are included asappendices.

Guideline for the Determination of Wetland Buffer Requirements2

The concept of wetlandbuffers

Buffering provides an important tool inachieving and maintaining the desiredvalues, processes, functions and attributesof wetlands. It involves separating awetland from the adjacent land use(s) thatmight threaten its desired values andensuring wetland activities do not haveundue impact on the land use(s), througheither spatial separation or the use ofphysical barriers.

Figure 1 shows the proposed bufferingconcept in terms of the three basic areasrequiring definition to provide separation forthe wetland:

• the wetland water body;

• the wetland function area; and

• the separation requirement.

Only permanently inundated wetlands willhave a visible area of open water - thewetland water body, all year round. Somewetlands, such as waterlogged areas,never have an open expression of water.Additional information on wetland types iscontained in application note 1.

The wetland function area is the area whichneeds to be protected to ensure theimportant functions and values of thewetland can be maintained. The wetlandfunction area is the spatial boundary of thewetland. It normally would include thewetland itself and the wetland vegetation.The wetland function area is discussed ingreater detail in application note 3.

The wetland function area often will requireadditional separation from surrounding landuse(s) to ensure its protection andcompatibility with the land use. Separationcan involve two general forms: a physicalbarrier (fence, wall), or a separationdistance. These forms are not mutuallyexclusive, and in some cases, acombination can provide a solution. Keyconsiderations in defining separation needsare values, functions and attributes of thewetland to be protected, the characteristicsof the surrounding land use and the threatsassociated with the land use(s).

A separation distance is generallymeasured from the boundary of the wetlandfunction area; however, they may bemeasured from the boundary of the waterbody in cases of a permanent or seasonallyinundated wetland without significantecological values outside the inundatedarea.

The separation requirement effectively isthe furthest extent of the separationdistance required to deal with all separationissues (eg habitat protection, firemanagement, water quality management)specific to each proposed or existingadjacent land use. Activities compatiblewith the surrounding land use and themanagement objective of the wetland canbe permitted in all or part of the separationarea (eg passive recreation) in accordancewith the respective wetland managementplan.

separation distanceseparationrequirement

wetlandfunction area

wetland water body(in the case ofpermanent or seasonallyinundated wetland)

Figure 1 - Generalised wetland buffering concept(Welker Environmental Consultancy, 2002)


The process to determine an appropriatebuffer between a wetland and an existing orproposed land use requires the systematicconsideration of wetland attributes (existingor desired), threatening processesassociated with adjacent land use, and therole of the buffer in mitigating these threatsso the wetland values, functions andattributes are protected to the extent thatseparation measures can achieve thispractically. An individual approach isrequired to determine buffer requirements,rather than a “one size fits all” approach.

The approach requires completion of aseven step process (figure 2):

Step 1 Acknowledge existence of wetland

Step 2 Identify wetland attributes, wetland management categoryand establish management objective

Step 3 Define wetland function area

Step 4 Identify threatening processes

Step 5 Identify role of separation

Step 6 Establish separation requirement

Step 7 Apply separation requirement to proposal and assess its ability toachieve management objective.

The process is depicted in figure 2 anddescribed briefly below. The majority ofinformation is contained in individualapplication notes at the back of thisdocument, which should be used asnecessary to complete each step.

Step 1 Acknowledge existenceof wetland

Acknowledgment of the existence of awetland is the first step in the determinationof a wetland buffer. This step does notrequire any specific definition of thewetland area. The outcome is simplyagreement that a wetland of some formexists at a particular location.

Information regarding types of wetlandsand existing wetland mapping andidentification is contained in applicationnote 1.

Step 2Identify wetlandattributes, wetlandmanagement categoryand establishmanagement objective

A critical step in determining bufferingrequirements is the identification anddefinition of the management objective ofthe wetland.

Wetland evaluation requires an assessmentof the values, functions and attributes of thewetland which are used to establish anappropriate management category(application note 2). The information usedto establish the management category willaid in the determination of the wetlandfunction area and separation distance,steps 3 and 4 respectively.

Process for determination of wetland buffer


Step 1Acknowledge existence of wetland

Step 2Identify wetland attributes, wetland management category and establish management objective

Outcome: Wetland management category is assigned & critical attributes identified.

Management objective is established

Re-evaluate wetlandmanagement category using

EPA endorsed method.

Step 3Define wetland function area

Step 4Identify threatening processes

Step 5Identify role of separation

Step 7Apply separation requirement toproposal and assess ability of

separation to achieve managementobjective

Is the separation requirementachievable?

Proceed with proposal C Category wetlandsRefer proposal to EPA

R and M Category wetlandsEstablish alternative separation

requirement

Step 6Establish separation requirement

Can the managementobjective be met?

No Yes

Yes No

YesNo

Seek advice from DoEWAPC to determine proposal

NoYes

Proceed with proposal

Has wetland been assigned amanagement category?

Are existing wetland values, processes,functions and attributes consistent withthe assigned management category?

Assess existing wetland values,processes, functions and attributes

using an EPA endorsed methodologyto assign a management category

Figure 2 - Proposed process for determination of wetland buffer requirements


Current Swan Coastal Plain evaluationmethodologies are used to assign wetlandsto one of three management categories:

• C category (conservation): wetlandswith high conservation value for bothnatural or human use;

• R category (resource enhancement):wetlands with moderate natural andhuman use attributes that can berestored or enhanced; and

• M category (multiple use): wetlandsthat score poorly on both natural andhuman use attributes.

Each category has management objectivethat will ensure retention of the values,functions and attributes associated with thewetland (table 1).

Management objectives have beenidentified for all wetlands on the SwanCoastal Plain, from Gingin to Dunsborough,through evaluation work completed by theDepartment of Environment (DoE) (formerlythe Water and Rivers Commission) (TheGeomorphic Wetlands Swan Coastal Plaindataset can be accessed atwww.walis.wa.gov.au). If the wetland inquestion has already been assigned amanagement category, the features thathave formed the basis for that assignmentshould be re-evaluated to confirm themanagement category is appropriate.

If the management category for the wetlandis appropriate, the attribute(s) used as thebasis for categorisation should be

examined to identify the attribute(s) relevantto establishment of the buffer. Table 4should be used to help determine the keyattribute(s) of the wetland and the requiredfunction of the buffer. It is important toconsider not only the importance of theattribute to achievement of themanagement objective, but also the degreeto which a buffer is able to ensure retentionof the attribute.

If the management category is inconsistentwith the current state (ie the wetland maybe in an improved or more degraded state),the wetland should be re-evaluated using aDoE endorsed protocol and submitted tothe DoE for endorsement and update. Forfurther information, see the DoE websitehttp://www.environment.wa.gov.au orcontact the Wetlands Program, DoE.

Wetlands yet to be mapped by the DoE willrequire evaluation with an endorsedprotocol, to establish an appropriatemanagement category and objective.Contact the Wetlands Program, DoE forfurther information and advice or see theabove DoE website.

Once a management category has beenassigned and the critical wetland attributes– those considered essential to theachievement of the management objectiveand the effectiveness of the buffer - areidentified, proceed to step 3.

Category Objective

Conservation (C category) wetlands to preserve wetland (natural) attributes and functions

Resource Enhancement to restore wetlands through maintenance and (R category) wetlands enhancement of wetland functions and attributes

Multiple Use (M category) wetlands to use, develop and manage wetlands in the context ofwater, town and environmental planning

(Source: Hill et al, 1996).

Table 1: Wetland management category objectives


Step 3Define wetland functionarea

The wetland function area is the area whichneeds to be protected to ensure theimportant functions and values of thewetland can be maintained. It normallywould include the wetland, the wetlandvegetation and any directly associateddependent terrestrial habitat. If the wetlandfunction area is determined, after a siteassessment, to be less than the mappedboundaries, the wetland should be re-evaluated and the results submitted tothe DoE so the mapping can be updated.

Information to help define the wetlandfunction area is contained in applicationnote 3. Once the wetland function area hasbeen defined, proceed to Step 4.

Step 4Identify threateningprocesses

The key threatening process(es) for thewetland attributes identified in Step 2should be identified based on considerationof the environmental risks of the varioussurrounding existing and proposed landuses.

There are many anthropogenic threats towetlands; however, not all of them may bemanaged through separation or provision ofa buffer. Those that can be mitigated (atleast in part) by buffering are:

• alteration to the water regime;

• habitat modification (grazing inwetlands, invasion of exotic species,clearing);

• inappropriate recreational use; and

• diminished water quality (nutrients,organic compounds, suspendedsolids, toxic compounds and salinity).

Table 6 provides a guideline for theidentification of relevant threateningprocesses associated with the variouscategories of land use. Once these havebeen identified relevant to the criticalwetland attributes, proceed to Step 5.

Step 5Identify role of separation

The wetland function area often will requireadditional separation from surrounding landuse to ensure its protection andcompatibility with the surrounding land use.Key considerations in defining separationneeds are the values, functions andattributes of the wetland and the threatsassociated with the surrounding land use.

The separation requirement effectively isthe furthest extent of separation distancesrequired to deal with all separation issues(eg, habitat protection, fire management,water quality management) specific to eachproposed or existing adjacent land use.

It is important to identify the role of theseparation requirement for each wetlandattribute. This will help to assess the abilityof the achievable separation requirement tomeet the management objective of thewetland (step 7) and provide the context forany additional separation area managementrecommendations.

Table 7 should be used to identify the roleof the separation requirement in mitigatingthreatening processes associated withadjacent land use. When the role of theseparation with regard to wetland attributesand adjacent land use has beendetermined, proceed to Step 6.


Step 6Establish separationrequirement

The recommended separation requirementsin this guideline are based on considerationof the associated threats and are a factor ofthe wetland’s management category.Different separation measures are requiredto achieve the different managementobjectives associated with eachmanagement category.

Tables 8, 9 and 10 set out by wetlandcategory, the separation requirementrecommended to mitigate the keythreatening processes associated with thecritical wetland attributes. When theappropriate separation requirement isestablished, proceed to step 7.

Step 7Apply separationrequirement to proposaland assess ability ofseparation to achievemanagement objective

This step involves the overlay of therequired separation on the proposal toassess whether it can be achieved. If so,proceed with the proposal.

If the required separation is unachievable,i.e. the recommended separation distancecannot be achieved around the wholewetland function area or the recommendedmanagement measures are unable to beimplemented, an assessment of what isachievable is required. If it can bedemonstrated clearly that the achievableseparation (ie separation distance,management measures or a combination of

both) will ensure that the appropriatewetland management objective is met,proceed with the proposal.

A reduction in the wetland boundary, therequired separation distance orrecommended management measures forC category wetlands is unlikely to meet theidentified management objective. In suchcases the proposal should be referred tothe EPA.

A reduction in the recommended separationrequirement for R category wetlands,provided it is not associated directly withthe critical wetland attributes and additionalmanagement measures are proposed toaddress the reduction, may meet themanagement objective.

M category wetlands generally are quitedegraded and may be weed infested dueto their existing use and/or lack ofmanagement. The likelihood of having anyattributes that require protection throughimposition of a buffer is therefore low.Accordingly, it is anticipated that themajority of proposals affecting M categorywetlands can be designed and managed tomeet the management objective.

Notwithstanding this, the wetland functionarea or separation distance determinedthrough this process may, in some cases,not be achievable because of existing orplanned development within the theoreticalbuffer area and/or the inability to avoid oradequately manage impacts from adjacentland use. However, modification to eitherthe proposal or the proposed managementof the buffer to result in an improvedoutcome may still meet the wetland’smanagement objective.

The critical wetland attributes and theassigned management category providethe context for decisions on the necessaryseparation distance and management.


Accordingly, these must be addressed inany argument for reduction of separationrequirement. Current technical informationshould be used in any justification formodified buffering needs.

If, after addressing the management oflikely impacts from the proposal, it can bedemonstrated that the wetland’smanagement objective can be met,proceed with the proposal.

Where the proposed separation may resultin an impact on wetland values, functions orattributes, appropriate approvals may berequired to implement the proposal. Inthese instances, the DoE should beconsulted so that an outcome that isacceptable in terms of environmentalbenefits can be achieved. If it cannot bedemonstrated that the wetland values andattributes will be enhanced or maintained,and the proposal cannot be modified toensure this outcome, particularly whereconservation category wetlands areinvolved, the proposal should be referred tothe EPA.


The guideline’s application notes aredesigned to facilitate ease of use, as theygive the user only the informationnecessary to complete the appropriatestep.

The information obtained from completingeach step should be tabulated in a formsimilar to Table 2, which allows easyidentification of critical elements. Itestablishes a clear process for determiningan appropriate separation requirement andallows individual consideration of attributes.

For example, an attribute of a wetland maybe the existence of waterbird breedinghabitat (step 2). The requirement tomaintain this attribute is to retain andprotect all areas used by the waterbirds forbreeding. This should include areas of

open water and seasonal inundation ordampness containing vegetation used bysuch birds for nesting and shelter.

This requirement can be translated into aboundary requirement (step 3) as, toincorporate this attribute, the wetlandfunction area should extend from thewetland core to include all areas of wetlandvegetation possibly utilised by waterbirds.The limit of wetland vegetation thereforedefines this boundary. The final wetlandfunction area is determined byincorporating the requirements to maintainall relevant attributes.

The table also can be useful to list thepotential threatening processes facing eachattribute (step 4) and identify the role of theseparation (step 5) using tables 6 and 7.

Step 2 Requirement to Step 3 Step 4 Step 5Attribute support attribute, Definable Threatening Role of separation

for the purpose boundary/extent processesof defining wetland function area

Migratory birdhabitat/breedingground (protectedunderJAMBA/CAMBA)

Maintain areas ofopen water,seasonally inundatedareas used forbreeding and otherareas of vegetationlikely to be used byspecies

Boundary ofwetland as mappedby GeomorphicWetland Databaseplus surroundingvegetated areasknown to be usedby birds

• Alteration to thewater regime

• Habitat modification

• Inappropriate recreational use

• Protection from direct disturbance or otherchange/impact to thewetland functionarea

• Can provide indirect support for wetland function area) through hydrological and terrestrial processes (eg external origin of resources)

(Source: adapted from Welker Environmental Consultancy, 2002).

Table 2: Recommended format for completing steps 3 to 5

Using the Guideline


The appropriate separation requirementthen can be established from tables 8, 9and 10, depending on the managementcategory of the wetland.

It is also useful to summarise the criticalpoints on the summary sheet provided. Thisform is designed to provide a clear pictureof the key stages to help guide the userthrough the process. It enables the criticalinformation required under one step to beidentified and summarised before movingon to the next step.

Unless a significant amount of up-to-dateinformation relating to the wetland isavailable, the services of a suitablyqualified environmental professional arelikely to be required to complete thisguideline. Assistance may be required todefine the wetland function area,particularly the identification of thearea/feature required to support andmaintain the critical attributes of thewetland. The success of the wetland bufferhinges on the accurate definition of thewetland’s boundary.

A field trip should be made to view andtake photographs of the wetland itself. Thephotographs should show clearly thecondition of the wetland, all open water, anyexisting vegetation and evidence of use ofthe wetland (active or passive recreation orany industrial or rural activities that mayimpact on the wetland).

The examples in appendices 3, 4 and 5were completed using desktop informationonly. This shows that it is possible todetermine a buffer with existing information,particularly in the metropolitan region of theSwan Coastal Plain; however it isrecommended that a field trip is undertakento update the field work. This allows

confirmation of the management categorybased on up-to-date information, especiallyif limited or no management of the wetlandhas occurred to date.


Wetland Buffer Definition Summary SheetStep 1 Location of wetland . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Step 2 Management category . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Management objective . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Critical attributes – high relevance of Area required to support attributeattribute and high importance to buffering (see Table 4)

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Step 3 Greatest extent of wetland function area . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Step 4 Adjacent land use(s) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

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Threatening processes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

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Step 5 Critical role of separation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Step 6 Separation requirement Minimum distance from WFA . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Management measures . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Step 7 Is separation requirement achievable? Yes No


1.1 Step 1

Acknowledgment of the existence of awetland is the first step in the determinationof a wetland buffer. This step does notrequire any specific definition of thewetland area. The outcome is agreementthat a wetland of some form exists at aparticular location.

1.2 Definition of wetlands

Wetlands are defined as:

"areas of marsh, fen, peatland orwater, whether natural or artificial,permanent or temporary, with waterthat is static or flowing, fresh,brackish or salt, including areas ofmarine water the depth of which atlow tide does not exceed six metres".(UNESCO, 1971)

This definition is from the RAMSARConvention on Wetlands of InternationalImportance (to which Australia is asignatory) and which has been adopted inthe Wetlands Conservation Policy forWestern Australia (Government of WesternAustralia, 1997).

Although rivers, creeks, estuaries, caves,and shallow marine areas fall within thisdefinition, their special attributes, values,protection and management requirementsfall outside the scope of this guideline andwill be addressed primarily through otherguidelines or policies.

Wetland types in Western Australiagenerally are categorised according toSemeniuk (1987), who proposed thatwetlands could be classified according tolandform (basin, channel, flat, slope,highland) and the longevity with whichwater is contained (permanently inundated,seasonally inundated, intermittentlyinundated and seasonally waterlogged).Wetlands may be classified as the followingtypes, as outlined in Table 3. This guidelineis not proposed to apply to intermittentlyinundated wetlands and channel wetlands(as noted above).

The catchment of a wetland can be definedas the area within which any activitiesundertaken have the potential to affect thewater quality or water levels in the wetlandfunction area. However, surface andgroundwater catchments should beexcluded from specific consideration indetermining separation distances.

Water Longevity Landform

Basin Channel Flat Slope Highland

Permanently inundated lake river - - -

Seasonally inundated sumpland creek floodplain - -

Intermittently inundated playa wadi barlkarra - -

Seasonally waterlogged dampland trough palusplain paluslope palusmont

Table 3: Wetland types (after Semeniuk, 1987)

Application note 1:Acknowledge existence of wetland


Information on the presence of wetlands onthe Swan Coastal Plain may be obtainedfrom the Geomorphic Wetlands SwanCoastal Plain dataset (DoE). The datasetcan be accessed at www.walis.wa.gov.au(the DoE has A Guide to Viewing WetlandInformation on the WALIS website), oralternatively, contact the Wetlands Programat the DoE. For information regardingwetlands outside the Swan Coastal Plain,contact the relevant regional office of theDoE.

If it is possible to modify the proposal toexclude the wetland at this stage, it shouldbe done. This action is consistent with thecurrent EPA position which states that “theEPA places great importance on theprotection of the remaining wetlands andexpects that in the first instance,proponents will conduct a thoroughappraisal of all development options,including proper consideration of siteselection, that would avoid direct or indirectimpacts on wetlands” (EPA, 2001).


Wetland evaluation is a process used todescribe and weigh a wetland’s existingand potential values (Hill et al, 1996). It ishelpful to be precise in the description ofwetland values, characteristics, functionsand attributes, so that they are more readilyunderstood and communicated.

2.1 Wetland values, functions and attributes

Wetland characteristics and attributes giverise to environmental values or functions,which in turn may support or protect thebeneficial uses of wetlands (EPA, 1999).The following definitions are taken fromClaridge (1991) as outlined in Hill et al(1996) with the exception of ‘wetlandfunctions’ which was adapted from thedefinition provided in DoE’s internet siteglossary.

Wetland values are a measure orexpression of worth placed by society on aparticular function, use or attribute.

The characteristics are those properties ofa wetland which describe the area in thesimplest and most objective possible terms(eg wetland size, species present, soil type,water quality). Characteristics, singly or incombination, give rise to benefits (existingor future) which may be functions, uses orattributes of a wetland.

Wetland functions are the physical,chemical and biological processesoccurring within a wetland.

A use is some direct utilisation of one ormore of the characteristics of a wetland.

An attribute of a wetland is somecharacteristic or combination ofcharacteristics which is valued by a groupwithin society, but which does notnecessarily provide a function or support ause.

Attributes include:

• richness or diversity of flora or fauna;

• landscape/aesthetic qualities;

• value as a cultural, symbolic orspiritual place by a defined groupwithin the community; and

• presence of rare, endangered oruncommon flora, fauna, communities,ecosystems, natural landscapes,processes or wetland types.

For a comprehensive list of characteristics,functions, uses and attributes, see Hill et al,(1996). More attributes are listed in table 4.

Wetland values can be categorised as:

• uniqueness

• naturalness

• habitat or collective attributes

• scientific attributes

• recreational attributes

Application note 2:Identify wetland attributes, wetlandmanagement category and establishmanagement objective


• aboriginal

• cultural/heritage

• educational

The first three values are natural attributes.The functions of wetlands reflected in thosevalues are considerable and includesupporting numerous species of flora andfauna through the provision of breeding andnursery areas, refuge and feeding areas.Representativeness is an additional valuethat needs to be considered as havingimportance (Bowen, Froend & O’Neil,2002).

Human uses of wetlands include thefunctions of stormwater retention orretardation, numerous forms of recreation,enhancement of urban developmentthrough the provision of ‘green’ corridors.Aboriginal and European heritage uses ofwetlands are extensive, including use as afood source and watering points.Educational and scientific study functionsalso are important human uses.

The Revised Draft Environmental Protection(Swan Coastal Plain Wetlands) Policy andregulations 2004, (EPA, 2004) proposes thatwetlands with at least one significant naturalattribute or at least two environmentalvalues listed in the regulations are worthy ofregistration for protection under the draftEnvironmental Protection Policy.

2.2 Wetland management categories

A wetland management category systemwas established by the EPA (1993b) inBulletin 686. This is the system currentlyendorsed by the EPA; however, currentpractices tend to use the system outlined in

Hill et al (1996). Accordingly, Bulletin 686 isunder review.

Hill et al proposes three wetlandmanagement categories:

• C category (conservation): wetlandswith high conservation value for bothnatural or human use;

• R category (resource enhancement):wetlands with moderate natural andhuman use attributes that can berestored or enhanced; and

• M category (multiple use): wetlandsthat score poorly on both natural andhuman use attributes.

The review of Bulletin 686 is not expectedto result in any change to the currentmanagement categories as it is purportedto result in the amalgamation into onedocument of the range of methodologiesalready used.

Wetlands are scored against a suite ofattributes (currently under revision by DoE)to determine their management category.Given the current revision of the attributesto be used and the scoring process, theinformation contained in this guideline isbased on an expectation of the generaloutcome of the revised categorisationsystem.

A management objective has beenidentified for all wetlands on the SwanCoastal Plain through evaluation workcompleted by the DoE. For furtherinformation regarding wetland classification,evaluation and mapping see the DoEwebsite http://www.environmental.wa.gov.auor consult the DoE Wetlands Program.


2.3 Step 2

In this step, the outcome is the assignmentof a management category to the wetlandwith its associated management objective.This step also requires the identification ofattributes considered to be critical to thewetland, the assignment of a managementcategory and the effectiveness of the buffer.

2.3.1 Determination of management category and objective

If the management category for the wetlandhas been previously determined (as is thecase for all wetlands on the Swan CoastalPlain from Gingin to Dunsborough), theattributes used as the basis forcategorisation should be re-examined toensure that they remain consistent with theassigned management category. TheGeomorphic Wetlands Swan Coastal Plaindataset can be accessed atwww.walis.wa.gov.au.

If there is any inconsistency between themanagement category and the current stateof the wetland, a re-evaluation by thelandowner is necessary. Application to theDoE Wetlands Program should be made toobtain the current re-evaluation protocol. Asthis guideline uses management categoriesas a basis for the final recommendations,the re-evaluation of the wetland should becompleted by the land owner and endorsedby the DoE before progressing to step 3.

Further information is available on the DoEwebsite http://www.environment.wa.gov.au.

If the management category has not beendetermined, there is a need for thelandowner to assess the existing wetlandvalues, processes, functions and attributesand assign a management category for thepurpose of establishing the buffermeasures. To categorise an unassessedwetland, an evaluation should be made byan appropriately qualified person using anEPA endorsed methodology. This stepcould involve either the two-tier method ofevaluation described in chapter 5 of Hill etal (1996) or the Semeniuk evaluationmethod. These two methods currently arebeing combined into one evaluationmethodology, which will form an update toBulletin 686 (EPA, 1993b).

Each management category has anobjective for management that will ensureretention of the attributes associated withthe wetland (table 1).

Once the management category has beenassigned, the appropriate objective can beallocated.

2.3.2 Identification of critical wetland attributes

Once the management category for thewetland has been established, theattributes used as the basis forcategorisation should be examined tounderstand those relevant to buffering. Not

Category Objective

Conservation (C category) wetlands to preserve wetland (natural) attributes and functions

Resource Enhancement to restore wetlands through maintenance and (R category) wetlands enhancement of wetland functions and attributes

Multiple Use (M category) wetlands to use, develop and manage wetlands in the context ofwater, town and environmental planning


Table 1: Wetland management category objectives (repeated)


all attributes can be protected throughwetland buffers. Therefore, those mostrelevant to buffers and to the establishmentof the management category should beidentified – the critical attributes.

Table 4 sets out the relative importance ofwetland attributes to achievement andprotection of the management objective forthe wetland category and provides ageneral description of the role of thewetland function area and the separationarea. As with a buffer distance, a degree ofindividual judgment is involved indetermining relative importance and table 4is intended as a guide only. Additionally, thetable is not comprehensive, as it would beimpossible to list all the attributes that maybe ascribed to wetlands in WA.Accordingly, case-specific considerationsare necessary and may result in somemodification to the outcomes.

Additional considerations:

• If already categorised, determine thefeatures that have given the wetlandits management category. Someinformation is provided in Hill et al(1996); however, some of thisinformation is now out of date andtherefore mapping in the GeomorphicWetlands Swan Coastal Plain Datasetalso should be referred to. If thewetland is recognised in System 6,the Directory of Important Wetlands inAustralia, the Register of the NationalEstate, the Perth - Bunbury WaterResources Allocation Plan orBusselton – Walpole water resourcesstudies, the values will be discussedin these reports.

• If applicable, determine thejustification for the wetland beingprotected by policy, such as listingunder an environmental protectionpolicy or Bush Forever, or conventionsuch as RAMSAR. The justification forthe listing of the wetland wouldprovide information on the most

significant ecological valuespreviously identified for that wetland.

• If the wetland is contained within anarea under conservation managementsuch as in a CALM-managedconservation reserve and/or regionalpark, values and attributes of thewetland may be listed in themanagement objectives for suchareas. Management plans often existfor these areas, particularly in thecase of regional parks, and should bereviewed for information relating tothe values of the wetland in questionin addition to listed wetlandsecological processes that the park orreserve is intended to maintain.

Additionally, the wetland values andfunctions could be assessed by reviewingexisting studies or conducting new studieson the wetland to investigate the presenceof attributes (table 4).

Studies that would contribute importantinformation include those investigating:

• vegetation and flora within andsurrounding the wetland to determinethe presence (attribute) of significantconservation (value) species orcommunities (maintenance of thesewould be functions of the wetland);

• fauna, in or associated with thewetland, to determine the presence(attribute) of fauna, their conservationsignificance (value) and how thewetland is used by this species iehabitat, food resource (these wouldbe functions of the wetland);

• vegetative and surface hydrologicallinkage to other wetlands and areasof remnant vegetation;

• water quality of wetland andcomparison with Australian and NewZealand Environment andConservation Commission guidelinesfor the maintenance of aquaticecosystems (2000);


• its relationship to groundwaterhydrology (ie recharge, discharge)and surface hydrology (eg filteringzone before river/estuary), whichwould be specific functions of thewetland;

• Aboriginal heritage / ethnographicvalue;

• its social significance through surveysof recreational and commercial use,perception in community, anddetermination of proximity to variousland uses, particularly residentialareas; and

• other key attributes in the evaluationmethods.

It is acknowledged that unless a significantamount of up-to-date information relating tothe wetland in question is available, it islikely that the services of a suitably qualifiedenvironmental professional will be requiredto complete this step. Assistance may berequired to undertake the above studies.These studies are important, as theyprovide current information to accuratelyidentify wetland attributes andcorresponding wetland boundaries. Theinformation also would ensure the attributesidentified were specific to the particularwetland, rather than being identifiedgenerally from a table or book.


Table 4: Relative importance of wetland attributes to achievement of management aims

Attribute Relevanceof attribute1

(H, M, L)2

IOB3

(H, M, L)Role of wetland functionarea

Role of separation

Ec

olo

gic

al

Presence of rare,endangered,restricted,endemic orvulnerablespecies and/orcommunities

H M L HC4 R5 M6

• Provides the habitat andecological context for thespecies and maintainsecological processes andbiodiversity essential forwetland integrity andresilience

• Protection from directdisturbance or otherchange/impact to thewetland function areas

• Can provide indirectsupport for wetlandfunction areas throughhydrological and terrestrialprocesses (eg externalorigin of resources)

Ecological orgeological featuresof national orinternationalsignificance

M M M M • Provides a context for theecological or geologicalfeature and maintainsecological processes andbiodiversity essential forintegrity and resilience

• Provides a geologicalcontext for the formationand/or resource



Constitute part of alinked naturalsystem such asdestruction woulddisturb adjacentwetlands or faunausing the system

M M M H • Can link adjacent wetlandfunction areas

• Provides an ecologicalcontext for the species,habitat and/or resource,and maintains ecologicalprocesses and biodiversityessential for integrity andresilience

• Can link adjacent wetlandSeparation Areas.Protection from directdisturbance or otherchange/impact to the WFA.Can provide indirectsupport for WFA) throughhydrological and terrestrialprocesses (e.g. externalorigin of resources)

Supports highhabitat diversity

H M L H • Provides an ecologicalcontext for the habitat andmaintains ecologicalprocesses and biodiversityessential for integrity andresilience



1 Relative importance of attribute relative to achievement of management category aims2 H, M, L: high, medium, low relative importance3 IOB: importance of buffering - Relative importance of buffering to achieving/protecting the attribute4 management category C: High conservation value5 management category R: Resource enhancement6 management category M: Multiple use

Habitat of plants oranimals at criticalstage of biologicalcycle or vulnerablestage of their lifecycle

M M L H • Provides an ecologicalcontext for the habitat andmaintains ecologicalprocesses and biodiversityessential for integrity andresilience

• Protection from directdisturbance or otherchange/impact to thewetland function area

• Can provide indirectsupport for wetlandfunction area throughhydrological and terrestrialprocesses (eg externalorigin of resources)


Table 4: Relative importance of wetland attributes to achievement of management aims (continued)


(H, M, L)2

IOB3


Role of separation

Ec

olo

gic

al

Important formaintainingspecies and/orecologicaldiversity

H M L HC4 R5 M6

• Provides an ecologicalcontext for diversity andmaintains ecologicalprocesses and biodiversityessential for maintainingthat diversity



Important regionalwildlife sanctuaryeven if flora/ faunaare not rare orendangered

M H L H • Provides an ecologicalcontext for the species,habitat and/or resource,and maintains ecologicalprocesses and biodiversityessential for integrity andresilience



Supports largenumbers offauna/flora or 1%of nationalpopulation

M M L M • Provides an ecologicalcontext for the species,habitat and/or resource,and maintains ecologicalprocesses and biodiversityessential for integrity andresilience



Seasonal ortemporary habitator breeding groundof large numbersof migratory birdsor nomadicanimals

M M L M • Provides an ecologicalcontext for the species,habitat and/or resource,and maintains ecologicalprocesses and biodiversityessential for integrity andresilience




Supports extensiveareas of emergentand fringingwetland vegetation

H M L M • Provides an ecologicalcontext for the species,habitat and/or resource,and maintains ecologicalprocesses and biodiversityessential for integrity andresilience






(H, M, L)2

IOB3


Role of separation

Ec

olo

gic

al

Water quantityand quality

H M H-L MC4 R5 M6

• Provides an ecologicalcontext for thephysicochemicalprocesses that occur within it

• Maintenance of biologicaland physical processescritical to wetland waterquality

• Vegetation interception anduse of nutrients in surfaceand subsurface flow

• Can suppress water tableslocally and reducesalinisation of surface soils

• Role highly dependent onhydrogeology andcatchment characteristics

Drainage (to andfrom) andpresence ofnutrient sources

H M L M • Acts as a discharge siteduring wet periods andpossibly as a rechargesite during dry periods

• Provides an ecologicalcontext for thephysicochemicalprocesses that occurwithin it

• Maintenance of biologicaland physical processescritical to wetland waterquality

• Vegetation interception anduse of water in surface andsubsurface flow

• Can suppress water tableslocally


• Role redundant wherechannelised (piped)discharge into wetlandoccurs

Supportssignificantproportion ofindigenous fish,food source,spawning ground,nursery ormigration path

M M L M • Provides an ecologicalcontext for the species,habitat and/or resourceand maintains ecologicalprocesses andbiodiversity essential forintegrity and resilience



Representativeexample ofwetland type,biogeographicalregion, function/role in river orcoastal system ormajor wetlandsystem/ complex

M M L M • Maintenance ofunique/representativecharacter and/or function

• Provides an ecologicalcontext for the attributesand maintains ecologicalprocesses and biodiversityessential for wetlandintegrity and resilience



Rare or unusualwetland within aregion

H M L M • Maintenance ofunique/representativecharacter and/or function




Ot

he

rc

rit

er

ia*




(H, M, L)2

IOB3


Role of separation

Ot

he

rc

rit

er

ia*

Australian heritagecommissioncriteria – importantfor natural orcultural history (4 separatecriteria)

H M L MC4 R5 M6

• Maintenance ofunique/representativecharacter and/or function




Unaltered orunusual wetlandvegetation, faunaor processes

H M L H • Maintenance of pristinecondition

• Provides an ecologicalcontext for the conditionand maintains ecologicalprocesses and biodiversityessential for wetlandintegrity and resilience



Important tomaintain thequality of humanor animal andplant life egvegetation toarrest soil erosion

M H H M • Maintenance ofunique/representativecharacter and/or function

• Provides an ecologicalcontext for the attributesand maintains ecologicalprocesses andbiodiversity essential forwetland integrity andresilience



Aesthetics H H M H-M • Maintenance of aestheticqualities

• Provides an ecologicalcontext for the qualitiesand maintains ecologicalprocesses andbiodiversity essential forwetland aesthetics

• Can add to as well asmaintain aesthetics ofwetland function area


Wildernessfunction

H L L H • Maintenance of wildernessfeatures, function (as forpristine) and social/culturalimportance

• Provides an ecologicalcontext for attributes andmaintains ecologicalprocesses and biodiversityessential for maintainingwilderness condition

• For maintenance ofwilderness function,separation should extendto wetland catchmentboundary

• Is an integral part of thesurrounding wilderness



Hu

ma

nu

se




(H, M, L)2

IOB3


Role of separation

Hu

ma

nu

se

Historical,archaeological orculturalsignificance

H-L H-L M-L MC4 R5 M6

• Provides an environmentalcontext for the featuresand cultural values andmaintains ecologicalprocesses and biodiversityessential for maintainingwetland condition

• Can add to as well asmaintain features ofwetland function area


• Protection of wetlandfeatures and functionintegral to cultural values


Passive recreation M H H-L M • Provides a focus forpassive recreation.Maintenance of recreationfeatures

• Provides an environmentalcontext for recreationattributes and maintainsecological processes andbiodiversity essential formaintaining wetlandcondition

• May be a focus for passiverecreation. Protection ofwetland features andfunction integral torecreation values.Protection from directdisturbance or otherchange/impact to the WFA

Active recreation L M-L H-L L • Provides a focus forpassive recreation

• Maintenance of recreationfeatures

• Provides an environmentalcontext for recreationattributes and maintainsecological processes andbiodiversity essential formaintaining wetlandcondition

• May be a focus for passiverecreation

• Protection of wetlandfeatures and functionintegral to recreationvalues. Protection fromdirect disturbance or otherchange/impact to thewetland function area

Effect on landvalues

L M H-L M-L • Maintenance of aestheticqualities

• Provides an ecologicalcontext for the qualitiesand maintains ecologicalprocesses and biodiversityessential for wetlandaesthetics







(H, M, L)2

IOB3


Role of separation

Hu

ma

nu

se

Researchresource/scientificimportance

H H H MC4 R5 M6

• Maintenance ofunique/representativecharacter and/or functionof research interest

• May be of research interest


Educationalsignificance

H H H M-L • Maintenance ofunique/representativecharacter and/or functionof educational interest

• May be of educationalinterest


Importantproductive area forcommercialendeavours, egfisheries

L M H H-M • Maintenance of wetlandfeatures, function andcommercial (direct orindirect) importance

• Provides an ecologicalcontext for attributes andmaintains ecologicalprocesses and biodiversityessential for maintainingproduction values



Cannot be defined by one attribute

(Source: Welker Environmental Consultancy, 2002)


The wetland function area means the arearequired to be protected to ensure theimportant values, processes, functions andattributes of the wetland can be maintained.The wetland function area normally wouldinclude the wetland itself, the wetlandvegetation and any directly associateddependent terrestrial habitat.

The wetland function area often will requireadditional separation from surrounding landuse to ensure its protection and to ensurecompatibility with the surrounding land use.Separation can be achieved via a physicalbarrier (fence, wall, etc.) or by a separationdistance. These forms of separation are notmutually exclusive, and in some cases, acombination can provide a solution.

The wetland function area will typicallyinclude, in addition to any open water, allwetland vegetation unless the managementobjective is such that the peripheralwetland vegetation need not be retained orconsidered.

For example, a small lake within grassedparkland may be classified for multiple use,where the only important wetland value is tosupport an area of open water. In this case,the wetland function area could berestricted to the high-water mark and wouldnot extend to the grassed parkland.

Definition of the high-water mark issomewhat problematic and suchboundaries should be considered on acase-by-case basis. Use of the highesthistorical water level is not a specificallydefined level as it may depend on severalfactors, not the least being the amount ofrecorded water level data available.

However, use of historical data isrecommended to ensure that the currentenvironmental conditions, such as lack ofrainfall, have not led to an uncharacteristicwetland state.

It is proposed that the wetland function areabe defined by the outer boundary of thewetland vegetation or the geomorphologicboundary, whichever is the larger, unless aspecific case can justify extension beyondthat boundary. Extension of the wetlandfunction area to surrounding uplandvegetation areas would not normally occurunless those areas served a specific role inmaintaining wetland processes and containor serve attributes associated with thewetland, consistent with the managementobjective. The issue of protection ofterrestrial fauna habitat that is remote fromthe wetland (even when the primary habitatis within the wetland function area) extendsbeyond the capacity of wetland buffers.

Application note 3:Define wetland function area




Figure 1 - Generalised wetland bufferingconcept (Welker Environmental Consultancy,2002) (repeated)


There is therefore a need to consider thosespecies and their habitat needs through aseparate environmental assessmentprocess.

This is consistent with the mapping ofwetlands undertaken to date by the DoEcontained in the Geomorphic Wetland swanCoastal Plain Databset and should be usedwhere available. All wetlands of the SwanCoastal Plain from Moore River toDunsborough have been mapped,evaluated and classified and a framework isbeing developed for wetlands in theremainder of the State. If a wetland has notbeen mapped and included on the dataset,advice should be sought from the DoEWetlands Program on the approach to beused to determine the wetland boundary.The Geomorphic Wetlands Swan CoastalPlain dataset can be accessed atwww.walis.wa.gov.au.

The issue of protection of upland habitatneeds to be considered as a separate(although associated) matter beyond thescope of wetland buffering. Notwithstandingthis, separation can be expected, at least inpart, to provide some protection for uplandhabitat.

3.1 Step 3

This step initially involves the assessment ofthe material used to evaluate the wetland interms of its management category to definethe boundary of the wetland function area.The wetland function area is the arearequired to be protected to ensure theimportant values, processes, functions andattributes of the wetland can be maintained.

For each attribute, the requirement tomaintain or retain that attribute should beidentified and then, where possible, relatedto a definable boundary centred on the

wetland. It can be useful to tabulate therequirements to support significantattributes to determine the wetland functionarea (table 5).

The use of a table at this stage of theprocess allows the identification of therequirements to support the listed attributesof the wetland, together with an estimationof the area applicable to this requirement.The latter is defined by a boundary aroundthe wetland, which differs in its extent awayfrom the wetland core according to theattribute being maintained by it.

It is possible that some of these boundarieswill be defined by the interface between anarea of bushland and another land use thatserves no role in supporting the particularattribute of the wetland, such as aresidential or industrial area containing nonative vegetation. This is highly likely in thecase of wetlands in well-established urbanareas, such as Yangebup Lake, whereresidential and industrial areas have beenestablished close to conservation wetlands.It should be noted, however, that smallroads (two lanes) separating bushland areconsidered by the DoE not to interrupt thewetland function area.

Where practicable, the wetland functionarea is defined as the area within themaximum extent of these boundaries. Thatis, if all boundaries were to be presented asan overlay on an aerial photograph of thewetland (the approach that isrecommended in practice), the wetlandfunction area is the envelope incorporatingall the boundaries. For example, animportant attribute of a wetland may be theexistence of waterbird breeding habitat. Arequirement to maintain this attribute is toretain and protect all areas used by thewaterbirds for breeding, which wouldinclude areas of open water and seasonalinundation or dampness containingvegetation utilised by such birds for nesting


and shelter. This requirement can betranslated into a boundary definition as, toincorporate this attribute, the wetlandfunction area should extend from thewetland core to include all areas of wetlandvegetation possibly used by waterbirds.The limit of wetland vegetation thereforedefines this boundary. The final wetlandfunction area identified is the result ofincorporating the requirements to maintainall relevant attributes.

It should be noted that if the final wetlandfunction area boundary is less than thatmapped in the geomorphic wetlandsdatatset, DoE will not alter the datasetunless it is demonstrated that the mappedboundary is not consistent with the truewetland boundary. For more information seethe Draft Protocol for proposingmodifications to geomorphic wetlandsdatatset.

Once the wetland function area has beenidentified, proceed to Step 4.

Note: A table can be useful in listing the potential threatening processes facing each attribute and identifying the role of a separation requirement using tables 6 and 7 as a guide. A table of the attributes of the Coogee Springs wetland is presented as an example in Table 5.

Attribute Requirement tosupport attribute,for the purpose ofdefining wetlandfunction area

Definableboundary/extent

Key threateningprocesses

Role of separation

Part ofsignificantregionalwetlandsystem

Maintain wetlandarea

Boundary ofwetland asmapped in theGeomorphicWetland SwanCoastal PlainDataset held byDoE

• Alteration tothe waterregime

• Habitatmodification


• Can provide indirectsupport for wetlandfunction area) throughhydrological andterrestrial processes (eg external origin ofresources)

Remnantwetlandfringingvegetation

Maintain areascontainingemergent wetlandspecies

Boundary ofwetland asmapped in theGeomorphicWetland SwanCoastal PlainDataset held byDoE



• Diminishedwater quality



Table 5: Defining the wetland function area for each attribute

Table 5 continued next page


Attribute Requirement tosupport attribute,for the purpose ofdefining wetlandfunction area


Key threateningprocesses

Role of separation

Supports largerange ofmacroinverte-brate fauna

Maintain naturalwater levels.Protect fringingMelaleucas thatare withinseasonallyinundated zone

Areas permanentlyor seasonallyinundated






Waterbirdbreedinghabitat

Maintain naturalwater levels.Protect fringingwetland vegetation

Areas permanentlyor seasonallyinundated andcontaining wetlandvegetation





Potentiallyprovideshabitat and/orrefuge for arange of frogs,reptiles, birds,and mammals,not otherwisepresent(associatedfauna)

Maintain all areason whichassociated faunaare dependent,such that localrepresentation isnot affected

Extending fromwetland to averageknown extent offoraging/ use ofassociated fauna



• Inappropriaterecreational use




Visual amenityof open water

Maintain seasonalwater levels

Areas seasonallyinundated



• Protection from directdisturbance or otherchange/impact towetland function area


Table 5: Defining the wetland function area for each attribute (continued)


The key threatening process(s) should beidentified, based on consideration of theenvironmental risks of the varioussurrounding land uses. These threateningprocesses should also be associated withthe wetland attributes identified in Step 2.

4.1 Threats to wetlands

There are many anthropogenic threats towetlands; however, not all of them may bemanaged through separation or provision ofa buffer. Those that can be mitigated (atleast in part) by buffering are:

• alteration to the water regime;

• habitat modification (eg grazing inwetlands, invasion of exotic species,clearing);

• inappropriate recreational use; and

• diminished water quality (nutrients,organic compounds, suspendedsolids, toxic compounds and salinity).

These threats are discussed in more detailin the following sections and summarised intable 6. For a comprehensive list ofanthropogenic threats to wetlands, seeBowen, Froend & O’Neil (2002).

4.1.1 Alterations to the water regime

All wetland processes are maintained bythe associated water regimes and anyalteration to the regime will result inchanges to the flora and fauna.

Water regimes can be changed throughseveral means. Those relevant to wetlandbuffering include:

• removal of vegetation (affects thewater balance through reducedinterception and transpiration);

• development of impervious surfaces(increases water interception, butmay increase groundwater recharge ifconcentrated and directed to sumps);and

• directing drains or diverting naturalcreeks into or away from wetlands.

Wildlife impacts of changing water levelsinclude loss of nesting sites and foodsources, lowered biodiversity andemergence of exotic predators.

Groundwater pumping clearly can influencewetland water-level regimes but is not dealtwith here as buffering is an inappropriatemanagement response to deal with thiseffect.

Rises in water level cause deaths tofringing vegetation (which may relocate to ahigher elevation if it occurs slowly) and anincrease in habitat suitable to aquatic floraand fauna. This impact usually is caused byactivities in the catchment and bufferingagain is an inappropriate managementmeasure to control this. Removal of largeareas of vegetation close to the wetlandcan be managed, at least in part, throughinclusion of susceptible areas in a bufferingspace.

Buffering can assist management of theseimpacts through constraints on removal ordamage to vegetation close to the wetlandfunction area, control of land developmentclose to the wetland function area that will

Application note 4:Identify threatening processes


have a significant influence on verticalwater fluxes, and management orelimination of drains discharging intowetlands. Provision of a separation withappropriate controls is the primary bufferingmechanism.

4.1.2 Habitat modification

The primary modification of wetland habitatoccurs through the removal of vegetation.This includes wetland and uplandvegetation. Removal can be direct, throughclearing, or indirect, through means suchas fire, which also may result in loss ofnative seeders and sprouters.

Grazing in wetlands and associated uplandvegetation creates a threat when, forexample, certain native species areexcluded or inappropriate native speciesare introduced, or when feral animals orstock graze in wetlands. The impacts areloss of habitat (eg, preferred food species,shelter, roosting areas), competition withnative animal food sources, and physicaldamage to vegetation.

Management measures include:

• fencing to prevent stock and feralanimals entering the wetland;

• providing alternative watering points;

• controlling stock densities; and

• culling feral animal populations.

The invasion of wetlands by exotic speciestypically occurs after wetlands andassociated upland vegetation are disturbedor degraded. Exotic plant species cansmother or inhibit native vegetation, alterorganic matter fluxes, inhibit lightpenetration (shading out benthic plants),interfere with water movement, changeevapotranspiration, alter water quality andcreate fire hazards. Nearby residential andagricultural areas are a particular source of

weeds and exotic plants that can create arisk of invasion of wetland areas.

Exotic animals can compete with and preyon native species. Species such as carpcan increase turbidity, reduce invertebratenumbers and cause declines in numbers offish and wetland plants.

Buffering can help manage these impactsthough constraints on removal or damageto vegetation, fencing, and controllingexotic animal populations.

4.1.3 Inappropriate recreational use

The ability to use wetlands is consideredone of the most important attributes ofwetlands by the general community.Recreational use may be active, such aswater skiing, swimming or horse riding, orpassive, such as bird watching, picnickingor research. Use of wetlands by thecommunity, however, sometimes results inimpacts on the wetland that are detrimentalto its values.

Recreation impacts on wetlands andassociated upland vegetation includetrampling of vegetation, bank erosion,pollution and disturbance of wildlife.Buffers, particularly physical barriers, arean effective way of managing many impactsfrom inappropriate use in urban and ruralareas. Appropriate management ofrecreational usage such as through fencing,regulation, signage (education) andprovision of vegetated areas whichenhance degraded wetlands andencourage people to use them instead ofhigh conservation wetland areas, arerelatively simple ways of minimising oreliminating this type of impact on wetlands.

The appropriateness of use of wetlandslargely is a function of the management


category of the wetland. It is unlikely thatactive recreational pursuits are appropriatein C category wetlands, where they may beacceptable in R and M category wetlands.For guidance on appropriate use ofwetlands, refer to the relevant wetlandmanagement plan, CALM or the DoEWetlands Program.

4.1.4 Water quality

Pollution affects the full range of wetlandecosystem processes. Bunn et al (1997)categorised pollutants as:

1. Nutrients – nutrient enrichment is awidespread occurrence in wetlandsresulting in algal blooms that affectproductivity, create odours, spoil watertaste and appearance and can producetoxins (that can affect wetland biota ordrinking water supply quality). Effectson wetland biota can result in a changein species structure and diversity (bothflora and fauna).

2. Suspended solids and sedimentation –excessive amounts of sediment enteringwetlands can cause detrimental effectson plant and animal (vertebrate andinvertebrate) communities through agradual infilling of the wetland,smothering of flora and fauna andreduction of light transmission throughthe water column. This may occur as aresult of land clearing adjacent towetlands that leaves areas of bare soilthat are transferred to the wetland bywind and surface water flow.

3. Organic compounds – organic wastesfrom household effluent, animal wastesand urban runoff can foul water, buildup in the food chain, cause odours andincrease biological oxygen demand.Many organic compounds (eghydrocarbons, detergents) can be

irritants or toxic to fish and possibly toinvertebrates.

4. Toxic compounds – wetlands act assinks for many pesticides and otherchemicals used in wetland catchments.Pesticides and heavy metals form themain toxic materials of concern.Degradation of wetlands can affectwater chemistry (pH, chelating agents,etc) and enhance the toxicity of heavymetals. The presence of toxic material inwetlands is likely to be long term andchronic and where the material may notdirectly kill flora and fauna, it can makeit more susceptible to otherenvironmental stresses such as salinity.High concentrations of toxicants mayalso induce acute toxic effects,including flora and fauna death. Metalpoisoning can cause large algalgrowths though removal of algal grazersand competitive algae.

5. Salinity – secondary salinisation where awetland becomes unnaturally saline,primarily due to vegetation clearing.Salinisation may also occur from miningor industry discharges. Most biota havelimits to the salinity they can tolerateand salinity impacts on wetlands usuallyinvolve a change to more salt tolerantspecies.

The phenomenon of acidification of wetlandwater bodies through occasional dryingand oxidation of sediments has beenobserved recently in several locations. LakeGnangara is a recent example. Landclearing and artificial lowering of watertables in susceptible areas also may induceacidification of surface and groundwaterentering wetlands. For further information,refer to Planning Bulletin 64 Acid SulfateSoils (WAPC, 2003) or the DoE Acid SulfateSoils Guidelines Series atwww.environment.wa.gov.au/contaminatedsites


The primary role of buffering in managingwater quality is through management orelimination of drains carrying pollutantsdischarging directly into wetlands or theirbuffers. It also is important to eliminatetreatment basins which may contaminatethe groundwater of the wetland or overflowinto the wetland.

Buffering incorporating the use of biologicalfilters should be considered; however, thiscan be expected to play a significant roleonly with surface water inflows.Groundwater inflows are more problematic,particularly in areas such as the SwanCoastal Plain where the ability of wetlandfringing vegetation to take up nutrientsbefore they enter wetlands via thegroundwater through-flow will be limited.

Apart from minimising drainage dischargesdirectly into wetlands, the most effectivemeans of managing wetland water quality isthrough catchment management processesrather than buffering.

4.2 Environmental risk ofvarious land uses

Different land uses generate differentthreats to wetlands. While specific land usedevelopment proposals need to beevaluated on a case-by-case basis, thefollowing general risks apply to the variousmajor land use categories.

4.2.1 Rural land uses

Rural land uses fall into two broadcategories: broad acre farming andintensive agricultural industries. Bothconstitute risks to wetlands.

Land clearing is the primary threat commonto both categories. Broadacre farmingintroduces exotic animals and plants andpresents risks from predation andovergrazing. Use of pesticides andfertilisers are risks common to mostagricultural uses, independent of intensity.

Intensive agricultural industries such ashorticulture and animal feedlots presentthese risks in a substantial form. Piggeriesare a particular intensive agricultural pursuitunsuited to being close to wetlandsbecause of the high nutrient outputs. Stocktrampling and overgrazing of understoreyare common occurrences.

Salinity effects on wetland areas are theresult of land clearing to support broadacrefarming. Land clearing also causes rises ingroundwater and associated wetland waterlevels, resulting in drowning of fringingvegetation.

Special rural land use zonings create somerisks as a range of activities can be carriedout on rural lifestyle properties, many ofwhich may in effect be light industrial ratherthan agricultural. Activities such as vehicleand machinery maintenance create similarrisks to light industrial activities throughinput of organic and inorganic pollutantsand nutrients. The proximity of rural lifestyleproperties can generate opportunities forinappropriate recreation, including horse-riding trails.

Groundwater abstractions to supplyirrigation water for intensive horticulture canbe a major influence on wetland waterlevels. Buffering is an inappropriatemeasure to control groundwaterabstractions, however, bores should not bepermitted within the wetland function areaor separation area if likely to affect wetlandwater levels. This issue is best addressedby controlling groundwater abstractions to


ensure drawdown impacts on wetlands arewithin appropriate limits.

Artificial maintenance of wetland levelsthrough the addition of water to the waterbody is undertaken for several wetlands onthe Swan Coastal Plain and is an effectivemanagement measure in specificcircumstances.

4.2.2 Urban land uses

Urban land uses include residential, specialresidential, and light and heavy industry.

Apart from clearing pressures resulting fromcommercial opportunities from all forms ofland development in urban areas,residential land uses generate pressure onwetlands through the potential forinappropriate recreation, traffic noise, weedinfestation, drainage and stormwater run-off, pollutant discharges and groundwaterimpacts of contamination and abstractions.

There are numerous examples ofdevelopment of residential land increasinggroundwater recharge and permanentlyraising water levels, resulting in drownedfringing vegetation. This occurs through thecombined effect of clearing nativevegetation and the creation of imperviousareas that direct stormwater to sumpswhich increases the overall infiltration rateto groundwater from storm events.Examples of wetlands with drownedvegetation in the Perth metropolitan areaare Lake Claremont and Blue Gum Lake.

Eutrophication of wetlands occurs throughdrainage carrying lawn and gardenfertilisers into the water bodies. Organicmaterial in lawn clippings is a particularissue with residential areas.

Industrial areas carry the risks of noise andwater quality impacts through drainage

discharges and groundwatercontamination.

The aesthetic aspects of urban wetlandscreate pressures on water managers tomaintain permanent water in ephemeralwetlands. Periodic drying of wetlands isrecognised as being necessary to maintainwetland health and reductions in the rangeof water variation can cause water qualityproblems and other problems.

As in rural areas, groundwater abstractionsin urban areas create risks to wetlands andagain are better managed through controlson abstractions rather than buffering.

4.2.3 Other land uses

Other more specific land uses create avariety of risks. Clearly, reserves thatprevent land clearing and intensiveactivities are generally of low risk towetlands, and can provide good protection.However, silvicultural activities cansignificantly affect groundwater rechargerates and impact on wetland water levels.The State Forest 65 pine plantations atGnangara are attributed with causing asignificant reduction in recharge belownatural levels in areas not subjected toperiodic thinning to meet target basaldensities set to achieve groundwatermanagement objectives.

4.3 Step 4Table 6 provides a guideline for theidentification of threatening processesassociated with different land usecategories. Relevant threatening processesshould be identified through theassessment of possible impacts fromapplicable land uses. Once these havebeen identified for each wetland attribute,proceed to step 5.


Land use Alteration to thewater regime

Habitatmodification

Inappropriaterecreationaluse

Diminished waterquality

Broadacrerural

• Land clearing andwatertable rise withdrowning of vegetation

• Drainage to minimiseflooding

• Loss of vegetation

• Introduction ofexotic flora andfauna

• Overgrazing

• Loss of fringingvegetation anderosion from stocktrampling

• Powerboating onlarger waterbodies inremote areas

• Pesticides andfertilisers

• Salinisation

Intensive rural

• Land clearing andwatertable rise withdrowning of vegetation

• Drainage to minimiseflooding

• Groundwaterabstraction loweringwater levels

• Drainage into wetland

• Loss of vegetation

• Introduction ofexotic flora andfauna

• Loss of fringingvegetation anderosion from stocktrampling

• Horse ridingtrailsassociatedwith rurallifestyle living

• Pesticides andfertilisers

• Nutrients fromintensive animalindustries

• Some risk of organicand inorganiccontamination formrural lifestyle living

Urban/Residential

• Watertable rise throughreduced rainfallinterception and higherinduced recharge

• Use as drainagecompensating basis

• Groundwaterabstraction loweringwater levels

• Reduced dryingbecause of loss ofaesthetic value of waterbody

• Loss of fringingvegetation toprovide aestheticviews

• Encroachment toachieve maximumcommercial returns

• Uncontrolled accesstrails affectvegetation

• Traffic noise

• Weed infestation

• Feral and domesticanimals

• High populationpressures

• Rubbishdisposal

• Stormwater anddrainage dischargescarrying nutrientsand inorganic andorganic pollutants

Industrial • Watertable rise throughreduced rainfallinterception and higherinduced recharge

• Groundwaterabstraction loweringgroundwater levels

• Drainage into wetland

• Encroachment toachievemaximumcommercialreturns

• Noise impacts

• Stormwater anddrainage dischargescarrying nutrientsand inorganic andorganic pollutants

• Industrial pollutants

Other Silvicultural activitiesaffect rainfall recharge togroundwater

• Bank erosion

• Noise and otherdisturbances

• Water pollution

• Vegetationtrampling

• Introduction offeral animals

Key Threatening Process


Table 6: Summary of lands uses and associated threats Land Use


The wetland function area often will requireadditional separation from surrounding landuse to ensure its protection andcompatibility with the surrounding land use.Separation can involve two general forms: aphysical barrier (fence, wall), or a spatial,along-the-ground separation distance orarea. These forms are not mutuallyexclusive, and in some cases, acombination can provide a solution. Keyconsiderations in defining separation needsare the attributes of the wetland and thethreats associated with the surroundingland uses.

5.1 Separation

Separation (spatial separation and barrierseparation) has a broad role in achievingand protecting the range of valuesassociated with the management categoryand objective of any particular wetland.

Separation provides the following functions:(Bowen, Froend & O’Neil, 2002)

• reduces unchannelised acceleratedwater runoff from surrounding land;

• provides a physical barrier to slowsurface flows and mechanically trapsediment and debris and chemicallytrap nutrients, salt and othercontaminants;

• provides shelter in wind erosion proneareas;

• provides a native fauna corridor;

• provides screening betweenconflicting landscapes and/ordisruptive movement and/or noiseand/or approaching visitors;

• reduces the impacts of browsinganimals;

• reduces the effects of nuisanceinsects; and

• prevents invasion of unwanted plants;and provide aesthetic value.

A vegetated separation area performs thefollowing tasks in addition to those above:

• maintains water quality by filteringnutrients and trapping sediments;

• provides food, shelter and breedinghabitat for terrestrial and aquaticfauna;

• provides shade to lower watertemperature and increase oxygenholding capability of water body;

• provides shade to reduce nuisanceaquatic plants and algae;

• provides energy source from debrisfrom overhanging vegetation;

• provides food source for largerorganisms where invertebrates livingin vegetation are blown into the waterand;

• reduces flood and salinity risk byincreasing evapotranspiration;

• stabilises banks against erosion; and

• contributes to the tannin content ofthe water body reducing lightpenetration and consequentlyreducing incidence and severity ofalgal blooms. Colouring of water alsocan assist aquatic animals to hidefrom predators.

Areas of vegetation and grass also arerecommended to be used where overlandflow is the predominant medium for waterinput to wetlands7. This is because:

Application note 5:Identify role of separation


• vegetated areas can significantlyslow overland flow into wetlands, andthereby prevent polluted water,sediment and nutrients from reachingthe wetland and reducing erosivecapacity; and

• grassed areas are very effective inreducing overland flow andmechanically trapping sediments anddebris as well as nutrients (5 m widegrassed areas have been shown toremove about 70 per cent ofsediment and 90 per cent of nutrientsfrom run-off while an 8 m wide arearemoved up to 80 per cent ofsediments and a 9.1 m wide stripremoved from 96 per cent to 99.9 percent of nutrients)8. However grassedareas run the risk of causing weedinvasion into the wetland or addingnutrients if excessive fertilisers areapplied or lawn clippings escape intothe wetland. Consideration should begiven to using appropriate non-seeding grass species to reduce therisk of seed flowing into the wetland.

There is increasing recognition that diseasevector and nuisance insects such asmidges and mosquitoes can affect urbanresidential areas close to wetlands. It isacknowledged that risk of impacts fromdisease vector and nuisance insects needsto be considered in certain land planningdecisions. Midges and mosquitoesgenerally are controlled by chemicals, theuse of water sensitive design and/or theuse of buffers. Memorials on Title also areused to raise the awareness of the issuewith potential homebuyers in areas affectedseverely by mosquitoes.

This issue is beyond the scope of thisguideline, as it is a whole-of-governmentissue that requires a consistent approach

across the State. The issue of diseasevector and nuisance insects is addressedin greater detail from a planningperspective in Development of a PlanningPolicy for Mosquitoes and Development(DPI, 2001).

5.1.1 Separation distance and separation area

A separation distance is generallymeasured from the boundary of the wetlandfunction area; however, may be measuredfrom the boundary of the water body incases of a permanent or seasonallyinundated wetland with low ecologicalvalues.

The spatial form of separation can beconsidered as being a required setback orseparation distance. The terms separationdistance and separation area (figure 1) areused in this guideline as the term setbackcarries specific connotations that do not fit

7 Overland flow is a minor contributor to wetland water in areas such as the Swan Coastal Plain where sandy or other permeable soils allow high levels of infiltration and natural water input to wetlands predominantly is through the underlying groundwater.

8 Grassed areas must be grown without the use of excess fertilisers that can increase nutrient input to wetlands.




Figure 1 - Generalised wetland bufferingconcept (Welker Environmental Consultancy,2002) (repeated)


with allowing and managing activities inseparation areas. Additionally, use of theword zone also is avoided due to itsspecific planning meaning.

Figure 3 shows how the approach might beapplied where two wetland function areasare in proximity and the wetlands can belinked. In this example, the wetland functionarea and separation distance for eachwetland has been dealt with individually.Where the two wetlands are separate and inproximity (as shown) or where wetlandfunction ares overlap, there may be anoverall benefit in linking them, at least interms of the separation distances, and insome cases, the wetland function areas, toprovide a wetland corridor.

This approach would be appropriate in thesituation of wetland suites and regionalparks, where the benefit of linking thewetlands is determined, on balance, tooutweigh the disadvantages of prohibitingactivities within the increased separationarea and wetland function areas.

Areas that may be added towetland function area andseparation area if there issignificant net benefit inlinking wetlands

Figure 3 - Linking wetlands (Welker Environmental Consultancy, 2002)

5.1.2 Physical barriers

In some circumstances, physical barriersmay provide an alternative to largeseparation area in certain circumstances,eg the use of a fence to keep domesticanimals from nearby residences out of thewetland function area, or use of a path tohelp prevent spread of seed. To achieve theabove through a separation distance wouldrequire a considerably larger separationarea. In addition, more intensivemanagement arrangements may berequired.

5.2 Separation requirement

The separation requirement effectively isthe envelope of the separation distance andmanagement required to deal with allseparation issues (eg habitat protection, firemanagement, water quality management)specific to each proposed or existingadjacent land use.


Activities compatible with the surroundingland use and the management objective ofthe wetland may be permitted in all or partof the separation area (eg passiverecreation) in accordance with the wetlandmanagement plan.

The separation of wetlands fromincompatible land uses helps to manageactivities that cannot be controlled ormanaged by regulatory agencies. However,wetland buffers should also besupplemented by catchment managementactivities, especially where they provide amore practical means of achieving thedesired aim than spatial separation.

5.3 Step 5

It is important to identify the role ofseparation as it relates to the individualwetland attributes to reduce the impacts ofthe adjacent land uses on the wetland (andvice versa). This will help to assess theability of the achievable separationrequirement to meet the wetland’smanagement objective (Step 7) andprovide the context for recommendationsfor management of the separation area.

For example, if one of the critical wetlandattributes is that it is a migratory bird habitatand breeding ground protected underJAMBA and CAMBA, the role of theseparation requirement is to protect thewetland function area from directdisturbance or other changes/impacts. Thisrole is vital to the maintenance of thewetland’s values and functions and must beassured through determination of the finalseparation requirement.

Table 7 sets out the role of separation in themitigation of threatening process(es)relevant to associated adjacent land use.This table should be used to identify therole of separation in accordance with thethreatening process(es) that would beexpected to apply.

When the role of the separation measures inmitigation of potential impacts (threateningprocesses) with regard to adjacent landuse(s) for each wetland attribute has beendetermined, proceed to Step 6.


Threatening process Role of separation

Alteration to the water regime • Reduces rates of surface (unchannelised) and subsurface inflow and therefore reduces potential for elevated levels and prolonged flooding

• Resists channelisation, thus decreasing erosion and rate of water flow

• Increases interception and evapotranspiration, reducing excessive flooding

• Assists in adjustments to changing water levels via the expansion and contraction of plant communities

• Vegetated wetland fringes may affect the water regime through increasing evapotranspiration losses from the groundwater system supporting the wetland

Habitat modification • Vegetated buffers are valuable in minimising disturbance to the wetland and reducing potential for colonisation by exotic species

• Fencing the perimeter of the buffer is effective in preventing access to the wetland by exotic terrestrial vertebrate fauna

• Adds to and maintains wildlife habitat of a wetland

• Firebreaks reduce potential for increased frequency of fire

Inappropriate recreational use • Vegetated buffers can be used to enhance the aesthetics of a wetland,encouraging people to use that wetland rather than those of high conservation value

• Provides barrier to visual and noise pollution

• Minimises public access and activities in certain areas and/or wetlands

Diminished water quality • Vegetated buffers assist in the reduction of nutrient inputs to wetlands through increased uptake and assimilation of surface and subsurface water-borne nutrients

• Reduces un-channelised surface water flow rates, allowing suspendedmaterial to settle prior to wetland entry

• Provides for management of drainage inputs (see Alteration to the water regime)

• Avoids eutrophic conditions in a wetland and reduces the dispersal and impact of midges on surrounding areas

• Hydrogeology within the catchment and immediately around and beneath the wetland has a significant influence on the effectiveness of a buffer with respect to water quality. The intensity of production of contaminants by the source is a major factor to be considered and managed

(Welker Environmental Consultancy 2002)

Table 7: Role of separation to address threatening processes


The recommended separation requirementsoutlined in this guideline are determined bythe likely impacts of adjacent land uses onthe wetland and its values. Requirementsare different for each management categorybecause different separation measures arerequired to achieve the different objectivesassociated with each managementcategory. The critical wetland attributesprovide additional context for decisions onseparation and management measures.

Recommended separation distances aregiven as ranges for several measures, inparticular for firebreaks, aestheticimprovements, and nutrient and sedimentcontrol. In a case-by-case assessment, thedistance should be determined by takinginto account the physical characteristicsrelevant to the wetland, including wetlandvalues and attributes, the surrounding landuse and the feature being mitigated for oragainst (threatening process).

The rationale for selection of a separationdistance should be justified in terms of thewetland’s site-specific characteristics. Forexample, with firebreaks, the distance isdependent largely upon the vegetation(height, flammability), susceptibility of thewetland to fire effects, and the risk posedby and/or to surrounding land use.Aesthetic improvements and barriercontrols are dependent on thecharacteristics of the surrounding land use.Noise control is governed by thecharacteristics of the potential noisegenerator. In the case of control ofsediment and nutrient inputs throughoverland flow, the influential parameters aresoil characteristics, slope of the land,vegetation cover (particularly in terms of its

ability to retard flow and trap or take upcontainments), and potential contaminationconcentrations.

The buffering requirements in this guidelinehave been determined generally on thebasis of management objective.Achievement of the management objectivemay require more than the proposeddistance, or may be able to be achievedwith less. Variation from the suggesteddistances needs to be considered on themerits of each case.

The recommended separation andmanagement to mitigate potential impacts(threatening processes) for category C, Rand M wetlands is shown in tables 8, 9 and10 respectively. To help identify attributesthat have high importance relative to theachievement of the aims of eachmanagement category, attributes shown intable 7 are listed.

6.1 Category C wetlands

Attributes identified as having highimportance relative to achievement of theaims of the conservation (C category)management category are:

Ecological • presence of rare, endangered, restricted, endemic or vulnerable species and/or communities;

• supports high habitat diversity;

• important for maintaining species and/or ecological diversity;

Application note 6:Establish separation requirement


• supports extensive areas of emergent and fringing wetland vegetation;

• water quantity and quality; and

• drainage (to and from the wetland) and presence of nutrient sources.

Other criteria • rare or unusual wetland within a region;

• Australian heritage commission criteria – important for natural or cultural history (4 separate criteria); and

• unaltered or unusual wetland vegetation, fauna orprocesses.

Human use • aesthetics;

• wilderness function;

• research resource/scientific importance; and

• educational significance.

Recommended separation andmanagement to mitigate potential impacts(threatening processes) for category Cwetlands is shown in table 8.

6.2 Category R wetlands

Attributes identified as having highimportance to achieve the aims of theresource enhancement (R category)management category are:

Ecological • important regional wildlife sanctuary even if flora/ fauna are not rare or endangered

Other criteria • important to maintain the quality of human or animal and plant life eg vegetation to arrest soil erosion

Table 8: Category C wetlands: Separation and management

Key threatening Recommended Separation and/or management Separation area managementprocess

Alteration to thewater regime

Regulation of groundwater abstraction as catchmentmanagement measure

• Area to be vegetated withdeep-rooted perennialvegetation

• Preferably native plantcommunities

• 6m firebreak minimum,inside of fence

• Fence to limit vehicle, stock,exotic fauna access

• Clear perimeter outside offence (path, firebreak, road.

• Fire control to maintainhabitat and species diversity

• Minimise trackaccess/clearing, maximisenative vegetation

• Management for waterquality outcomes as required

Habitatmodification

• 100 m weed infestation

• Up to 100 m for bird habitat dependent on extent ofuse

• 6-50 m firebreak

• Fence for controlling exotic fauna access

• ≥100 m to minimise edge effects

Inappropriaterecreational use

• ≥ 50 m to improve aesthetics

• ≥ 50 m for barrier

• Fence, paths for controlling access


• Drainage inflows eliminated or managed

• Where a proposal may affect wetland water quality,particularly through un-channelised flow, detailedsite specific work should be undertaken todetermine the specific separation measuresrequired, including management measures



Human use • aesthetics

• passive recreation

• research resource/ scientificimportance

• educational significance

R category wetlands can possess similarattributes to C category wetlands but thewetland may not be in as good condition orpossess as many attributes. The attributesof C category wetlands therefore should beused as a guide.

Recommended separation andmanagement to mitigate potential impacts(threatening processes) for Category Rwetlands are shown in table 9.

6.3 Category M wetlands

Attributes identified as having highimportance relative to achievement of theaims of the multiple use (M category)management category are:

Other Criteria • important to maintain the quality of human or animal and plant life eg vegetation to arrest soil erosion, management of water quantity and water quality

Human Use • passive recreation research resource/scientific importance

• educational significance

• important productive area for commercial endeavours eg fisheries

Recommended separation distances andmanagement to mitigate potential impacts(threatening processes) for M categorywetlands are shown in table 10.

Table 9: Category R wetlands: Separation and management




• Area to be vegetated withdeep-rooted perennialvegetation. Limited openareas of grass

• Controlled access to wetland(paths)

• 6 m firebreak minimum,inside fence (if required)

• Fence to limit vehicle, stockaccess

• Clear perimeter outsidefence (path, road)

• Fire control to minimisehazards and maintain habitatdiversity


Habitatmodification


• 50 m avifauna habitat

• 6 m firebreak


• 10 m - 50 m for improving aesthetics

• 10 m - 50 m for barrier

• Fence, paths for controlling access



• Where a proposal may affect wetland water quality,particularity through un-channelised flow, detailedsite-specific work should be undertaken todetermine the specific separation measuresrequired, including management measures



It is acknowledged that M categorywetlands generally are quite degraded,containing limited or no upland vegetationnot infested with weeds, most likelyresulting from uncontrolled access byhumans or animals. There often is limitedacknowledgement of the existence of thewetland and therefore inadequatemanagement has occurred. Accordingly, itis not anticipated that many M categorywetlands will require provision of a bufferbetween the wetland and the surroundingland use. The objective in these instancesis restoration of the wetland andenhancement of wetland values wherepossible.

6.4 Step 6

Tables 8, 9 and 10 set out, by wetlandmanagement category, the separation andmanagement recommended to mitigate thekey threatening processes associated withthe critical wetland attributes. These tablesshould be used to identify an appropriateseparation distance and recommend

management based on the key threateningprocesses identified in step 4 and themanagement category of the wetland.

The rationale for determination of aseparation distance should be justified interms of the site-specific characteristics.The separation requirement should berelevant to the critical wetland attributes asthey relate to the key threatening processesand the individual characteristics of thewetland.

Separation distances and managementmeasures are recommended on the basisof potential threats in order to mitigate likelyimpacts of the surrounding land use.Separation measures are required tomitigate only those threats that are present.For example, if there is no potential for lossof vegetation (habitat modification), there isno need for a separation requirement tomanage this impact. Similarly, if the onlythreat identified is the potential for alterationto the water regime, no separation distanceis required.

Table 10: Category M wetlands: Separation and management




• Area to be vegetated withdeep-rooted perennialvegetation. Limited openareas of grass

• Controlled access to wetland(paths)

• 6 m firebreak minimum,inside fence (if required)

• Fence to limit vehicle, stockaccess

• Clear perimeter outsidefence (path, road)

• Fire control to minimisehazards and maintain habitatdiversity


Habitatmodification


• 50 m avifauna habitat

• 6 m firebreak


• 10 m - 50 m for improving aesthetics

• 10 m - 50 m for barrier



• Where a proposal may affect wetland water quality,particularity through un-channelised flow, detailedsite-specific work should be undertaken todetermine the specific separation measuresrequired, including management measures



Generic separation measures arerecommended in the tables. It is thereforenecessary to ensure that the separationidentified is relevant to the attributeassociated with the threat.

The identification of an accurate separationdistance for firebreaks, aestheticimprovements, and nutrient and sedimentcontrol, which are recommended as rangesin the tables, also is necessary. Thesedistances should be determined by takinginto account the physical characteristicsrelevant to the values and attributes of thewetland, the surrounding land use and thefeature being mitigated for or against. Thisassessment is likely to require the servicesof a suitably qualified environmentalprofessional.

When the appropriate separationrequirement is established, proceed to step 7.


7.1 Step 7

This step involves the overlay of theseparation requirement on the proposal toassess whether the recommendedseparation measures can be achieved. Anaerial photograph should be used for thisstep. An overlay of clear film, which showsthe proposal, cadastral boundaries,contours to identify ridgelines andextrapolate areas of wetland vegetation,and other land use planning information,may be more useful than marking thephotograph. The wetland function area alsoshould be drawn on the overlay. Therequired separation distance then can bemeasured from the boundary of the wetlandfunction area.

7.2 Separation measuresachievable

If the required separation measures areachievable, ie the separation distance canbe achieved and recommendedmanagement measures implemented,proceed with the proposal.

7.3 Separation measuresunachievable

In a practical situation, existing landplanning decisions often make securingrequired buffering distances or necessaryassociated management regimesimpractical. Effectively this means thewetland management category objective isnot practically achievable withoutmodification of existing decisions or theproposal of arrangements to ensureretention and maintenance of wetlandvalues and attributes.

A simple example is where significantresidential development has already beenallowed to develop within therecommended separation distance. Theresidential land use is likely to compromisethe function of the wetland and thus theachievement of the management objectivesof the wetland.9

Figure 4 provides an indicative example ofwhere previous land planning decisionshave reduced the separation to an extentthat is not adequate to provide thenecessary separation. Within the area to thetop of the diagram, the separation distancecan be applied to its desired extent, but itis inhibited throughout the lower part of thediagram because of previous land planningdecisions allowing encroachment ofincompatible land uses.

Application note 7:Apply separation requirement toproposal and assess ability of separationto achieve management objective

9 If development exists within the wetland function area, this should have been identified in step 2 and a wetland re-evaluation undertaken at that stage.


Because the desired separation area hasbeen compromised by existingdevelopment, this may mean the values ofthe wetland function area potentially arecompromised unless proved otherwise.However, as the desired separation is stillable to be achieved around a significantpart of the wetland function area, additionalwork could be done that may demonstratethat the wetland will still be able to maintainits management category objective.

In figure 4, the area at the top of thediagram also contains land with highconservation value that extends beyondwhat is necessary for separation. This areawould be dealt with, in terms of setting itaside or putting a managed land use inplace, on its merits. It should not be dealtwith in the context of wetland buffering as itlies outside the area that by definition is

required for achievement of the wetland’smanagement objective.

If the required separation is unachievable,ie the recommended separation distancecannot be achieved around the wholewetland function area or the recommendedmanagement measures are unable to beimplemented, an assessment of what isachievable is required.

7.3.1 C category wetlands

In the case of C category wetlands, areduction in the required separationdistance or management is unlikely to meetthe conservation category managementobjective. If the boundary of the wetlandcould be compromised, the proposalshould be referred to the EPA.

A case may still be made for reducing therecommended separation for a C categorywetland. The argument should besubstantiated by up-to-date technicalinformation and evidence. Consultation withthe DoE Wetlands Program is required. .Every effort should be made to maximisethe achievable buffer and implementimproved management measures. This mayinclude modification of the proposal wherepossible. If a proposal is unable to achievethe recommended separation, referral to theEPA is required.

7.3.2 R and M category wetlands

Small reductions in the recommendedseparation for R and M category wetlands,provided the reduction is not associateddirectly with the critical wetland attributesand additional management measures areproposed to address the reduction, maymeet the appropriate wetland managementobjective.


Actual separation area(development pre-existsto this boundary)

Waterbody

Desirable separationarea - if no pre-existingdevelopment

Area of conservation value,but low significance interms of protection ofintegrity of wetland function

Figure 4 - Separation distance not able to beachieved (Welker Environmental Consultancy,2002) (repeated)


7.4 Establishing an alternative separation requirement

In certain circumstances, it may be desiredto create an outcome for the wetland that issignificantly different from the current stateof the wetland. Possible reasons for wishingto modify the current state include:

• inability to avoid or adequatelymanage impacts from adjacent landuse as a result of the inability toachieve the required separation thatprotects current values;

• inability to maintain the currentwetland function area which wouldresult in an impact on current values;

• desire to enable development toencroach on the wetland functionarea or its separation because theoverall net benefit of the developmentis extremely high and impacts cannotbe avoided or adequately managed;and

• desire to improve the current valuesof the wetland by enhancing itsfeatures.

A landowner might have defined therequired separation to maintain currentattributes consistent with the managementcategory but found the distance to beunachievable. An alternative separationthen should be proposed, together withadditional management measures thatmaximise the potential for the buffer toachieve the management objectives of thewetland. If there is scope to modify theproposal to achieve this, it should be done.

The alternative separation then should beevaluated for its ability to achieve thewetland’s management objective.

7.5 Does the alternative separation meet the wetland’s management objective?

The wetland management category andcorresponding objective provides anobvious context for management. Thedifficulty is in understanding what themanagement objective means.

In the majority of cases for C categorywetlands, current values should bemaintained and therefore proposals thatreduce the separation requirement areunlikely to be acceptable.

In the case of R and M category wetlands,current values should be maintained orenhanced where possible. The proposalmust ensure the future outcome for thewetland is equal to, or preferably betterthan, what exists. It must be demonstratedthat the potential impacts from the proposalwill not result in a reduction in the existingvalues, attributes or condition of thewetland. If the separation is unachievable,additional management must be proposedto reduce the impacts from the proposal tothe point where the existing condition of thewetland is enhanced, or at least, preserved.Table 11 outlines the management prioritiesfor the three categories of wetlands. Thisprovides the context for the desired futureoutcome of the wetland.


7.6 Making a case for an alternative separation requirement

Consultation with the DoE WetlandsProgram and the DPI Environment andNatural Resource Management Branchshould occur at this time.

The proposed separation should bejustified in terms of the wetland attributes itis desired to achieve and protect, and byimplication, its actual or expected futurestate as defined by its objective. Theidentification of attributes associated withthe wetland management category, andwhether the protection of those currentattributes can be achieved, forms the basisfor justification of an alternative separationrequirement. The case must besubstantiated with up-to-date technicalinformation, presented in a logical format.

The argument for reducing the separationrequirement should be based onconsideration of the overall balance ofsocial, environmental and economicaspects associated with the variousparameters that may affect the future of awetland. The original wetland evaluation willprovide information regarding some of thesocial considerations affecting the wetland.Economic considerations also are relevant,including the cost of ongoing managementand maintenance and who is responsiblefor this funding.

Stakeholder involvement in the decision-making process is a requirement on publicland, where the role of various regulatorsand responsibility for decision-making alsoneeds to be considered. Communityconsultation should occur where it is knownthat there is a community interest in thecurrent use and future outcome of thewetland.

Category Description Objective Management priorities

Conservation (C category)wetlands

Wetlands whichsupport highlevels of attributesand functions

Preserve wetland attributes and functionsthrough reservation in national parks, Crownland and protection under environmentalprotection policies

to preservewetland (natural)attributes andfunctions

ResourceEnhancement (R category)wetlands

Wetlands whichhave been partlymodified but stillsupportsubstantialfunctions andattributes

to restorewetlands throughmaintenance andenhancement ofwetland functionsand attributes

Restore wetlands through maintenance andenhancement of wetland functions andattributes by protection in Crown reserves,State or local government land and byenvironmental protection policies, or in privateproperty by sustainable management

Multiple Use (M category)wetlands

Wetlands with fewattributes whichstill provideimportant wetlandfunctions

to use, developand managewetlands in thecontext of water,town andenvironmentalplanning

Consider use, development and managementin the context of water (catchment/strategicdrainage planning), town (land use) andenvironmental planning through landcare


Table 11: Wetland management categories, objectives and management priorities


If, after addressing the management oflikely impacts from the proposal, it can bedemonstrated that the wetland’smanagement objective is able to be met,proceed with the proposal.

Where the proposed separation andmanagement, if implemented, may result ina change to the wetland values orattributes, appropriate environmentalapprovals may be required to enable suchan impact on the wetland. In theseinstances, it is recommended thatconsultation occur with the DoE, to identifyan approach that will result in acceptableenvironmental outcomes. The WAPC maybe unlikely to approve a proposal that is notsupported by the DoE. For R and Mcategory wetlands, a negotiated outcomewill need to be achieved in consultationwith the DoE. For C category wetlands, if itcannot be demonstrated that the wetlandvalues and attributes will be enhanced ormaintained, and the proposal cannot bemodified to ensure this outcome, theproposal should be referred to the EPA.


Australian and New Zealand Environment and Conservation Council, 2000, Australian andNew Zealand Guidelines for Fresh and Marine Water Quality, National Water QualityManagement Strategy, Commonwealth of Australia.

Balla S, 1994, Wetlands of the Swan Coastal Plain Volume 1 Their Nature and Management.Water Authority and Department of Environmental Protection, Western Australia.

Bowen B., Froend R., & O’Neil K., 2002, Literature Review of Wetland Values, Threats andthe Function and Management of Wetland Buffers, report to Welker EnvironmentalConsultancy by Froend Bowen & Associates, Perth, Western Australia.

Davies, P.M. & Lane, J. A. K., 1995a, Guidelines for Effective Buffer Zones for Wetlands ofthe Swan Coastal Plain, Report to Australia Nature Conservation Agency, Canberra,Australian Capital Territory, pp 64.

Davies, P.M. & Lane, J. A. K., 1995b, Effective buffers for wetlands, Wetlands Australia2: 9-10.

Davies, P.M. & Lane, J. A. K., 1996, Nutrient content of surface water discharge into LakeClifton; an internationally significant wetland, J. Roy. Soc. WA, 80: 121-136.

Davis, J., Rosich, R., Bradley, J., Growns, J., Schmidt, L., and Cheal, F., 1993, Wetlands ofthe Swan Coastal Plain, VolumeT Wetland Classification on the basis of Water Quality andInvertebrate Community Data, TEnvironmental Protection Authority and Water Authority ofWestern Australia, Perth, Western Australia.

Department for Planning and Infrastructure, 2001, Development of a Planning Policy forMosquitoes and Development, prepared for the Department for Planning and Infrastructureby Ecoscape (Australia) Pty Ltd and SJB Town Planning and Urban Design, Perth, WesternAustralia.

Department of Conservation and Land Management, 2001, Beeliar Regional Park – DraftManagement Plan, Perth, Western Australia.

Environment Australia (Department of the Environment and Heritage), 2000, EnvironmentProtection and Biodiversity Conservation Act 1999, Canberra, Australian Capital Territory.

Environmental Protection Authority, 1992, Environmental Protection (Swan Coastal PlainLakes) Policy 1992, Environmental Protection Authority, Perth, Western Australia, 1992.

Environmental Protection Authority, 1993a, Strategy for the protection of lakes and wetlandsof the Swan Coastal Plain, Report of the EPA, EPA Bulletin 685, Perth, Western Australia.

Appendix 1: Resource documents


Environmental Protection Authority, 1993b, A Guide to Wetland Management in the Perth andNear Perth Swan Coastal Plain Area – An update to EPA Bulletin 374, EPA Bulletin 686,Perth, Western Australia.

Environmental Protection Authority, 2005, Draft Guidance for the Assessment ofEnvironmental Factors: Guidelines for Environment and Planning, Guidance Statement No33, Perth, Western Australia.

Environmental Protection Authority, 1998a, Environmental Protection (South West AgriculturalZone Wetland) Policy 1998, Perth, Western Australia.

Environmental Protection Authority, 1998b. Guidance for the Assessment of EnvironmentalFactors Protection of the Lake Clifton Catchment, Guidance Statement No 28, Perth, WesternAustralia.

Environmental Protection Authority, 1999, Management of Surface Runoff from Industrial andCommercial Sites - Guidance for the Assessment of Environmental Factors, EPA DraftGuidance No. 26, Perth, Western Australia.

Environmental Protection Authority, 2004, Revised Draft Environmental Protection (SwanCoastal Plain Wetlands) Policy and Regulations 2004, Environmental Protection Authority,Perth, Western Australia.

Environmental Protection Authority, 2001, Environmental Protection of Wetlands - PreliminaryPosition Statement (Position Statement No. 4). June 2001, Perth, Western Australia.

Government of Western Australia, 1928, Town Planning and Development Act 1928, Perth,Western Australia.

Government of Western Australia, 1997, Wetlands Conservation Policy for Western Australia,Perth, Western Australia.

Government of Western Australia, 2000a, State Water Quality Management Strategy –Objectives, Principles, Strategies and Implementation Framework, Perth, Western Australia.

Government of Western Australia, 2000b. Bush Forever, Western Australian PlanningCommission, Perth, Western Australia.

Hill, A., Semeniuk, C. & V., Del Marco, A., 1996, Wetlands of the Swan Coastal Plain,Volumes 2A and 2B, Wetland Mapping, Classification and Evaluation, Water and RiversCommission and Department of Environmental Protection, Perth, Western Australia.

Semeniuk, C. A., 1987 Wetlands of the Darling System – A geomorphic approach to habitatclassification. Journal of the Royal Society of Western Australia 69: 95-112.

Storey, A., Vervest, R., Pearson, G., and Halse, S., 1993, Wetlands of the Swan Coastal Plain,Volume 7, Waterbird Usage of the Swan Coastal Plain, Environmental Protection Authorityand Water Authority of Western Australia, Perth, Western Australia.


Streamtec Ecological Consultants, 2001, Estimating required buffer widths for Swan CoastalPlain wetlands, Report ST 23/01.

Water and Rivers Commission, 2000, Wetland buffers, Water Notes (Advisory Notes for LandManagers on Rivers and Wetland Restoration), January 2000, Perth, Western Australia.

Water and Rivers Commission, 2001, Wetlands Position Statement (6 June 2001), Perth,Western Australia.

Water and Rivers Commission, 2002. A Guide to Viewing Wetland Information on the WALISwebsite, Perth, Western Australia.

Welker Environmental Consultancy, 2002, Study into Buffering Between Wetlands and OtherLand Uses: A Management Framework for Wetland Buffering, Report prepared for theDepartment for Planning and Infrastructure, Perth, Western Australia.

Welker Environmental Consultancy, 2003, Buffering Between Wetlands and Other Land Uses:A Guideline for the Determination of Wetland Buffering Requirements. Report prepared forthe Department for Planning and Infrastructure, Perth, Western Australia.

Western Australian Planning Commission, DC Policy 2.3 (Public Open Space in ResidentialAreas), Perth, Western Australia.

Western Australian Planning Commission, 2003, Planning Bulletin 64 Acid Sulfate Soils.

Websites:www.environment.wa.gov.auwww.dpi.wa.gov.auwww.walis.wa.gov.au


AHD Australian Height Datum.

anthropogenic affected by or related to humans.

benthic relating to or living in or on the bed of a body of water including the silt or mud that lies there.

bio-diversity variety of life forms: different plants, animals and micro-organisms, genes they contain, ecological functions they perform and ecosystems they form. It is usually considered at three levels: ecosystem diversity, species diversity, and genetic diversity.

buffer separation of a wetland from adjacent land use through either spatialseparation or the use of physical barriers to reduce the threats to desired values and attributes and ensure wetland activities do not have undue impact on the land use.

CALM Department for Conservation and Land Management.

conservation management of human use of the biosphere so that it may yield the greatest sustainable benefit to present generations, while maintaining its potential to meet the needs and aspirations of future generations. Thus conservation is the positive, embracing, preservation, maintenance, sustainable utilisation, restoration and enhancement of the natural environment.

creek type of wetland, a seasonally inundated channel (Semeniuk, 1987).

dampland type of wetland, a seasonally waterlogged (damp) basin of variable size and shape (Semeniuk, 1987).

directly associated dependent terrestrial vegetation vegetation that occurs in association with a particular wetland. Also

referred to as wetland vegetation.

DoE Department of Environment.

DPI Department for Planning and Infrastructure.

ecosystem defined community of organisms, their interaction, and their physicalsurroundings (Department of Environment, Sport & Territories (1994).State of the Environment reporting: Framework for Australia. 42pp, Canberra, ACT).

environmental value beneficial use or an ecosystem health condition (ie, a condition of the ecosystem relevant to the maintenance of ecological structure, ecological function or ecological process).

ecological integrity physical, chemical and biological components of an ecosystem and the interactions between those components, being in a sound, undiminished and unimpaired state.

EPA Environmental Protection Authority.

Appendix 2: Definitions


EPP environmental protection policy.

evapotranspiration the transfer of water into the atmosphere through evaporation from the land and transpiration from plants and animals and can be calculated from the difference between precipitation and the amountof run-off.

floodplain type of wetland, a seasonally inundated flat (Semeniuk, 1987).

inter-generational equity principle that the present generation should ensure that the health,

diversity and productivity of the environment is maintained or enhanced for the benefit of future generations.

lake type of wetland, a permanently inundated basin of variable size and shape (Semeniuk, 1987).

palusplain type of wetland, a seasonally waterlogged flat (Semeniuk, 1987).

paluslope type of wetland, a seasonally waterlogged slope (Hill et al, 1996).

river type of wetland, a permanently inundated channel (Semeniuk, 1987).

separation area area between the boundary of the wetland function area and the outer limit of the separation requirement that extends as far as the separation distance.

separation requirement furthest extent of the separation distances required to deal with all

separation issues (eg, habitat protection, fire management, water quality management) specific to each particular proposed or existing adjacent land use.

silviculture the science and economics of the establishment, management, composition and growth of forests.

sumpland type of wetland, a seasonally inundated basin of variable size and shape (Semeniuk, 1987).

upland vegetation vegetation that exists outside the wetland function area.

WALIS Western Australian Land Information Service.

WAPC Western Australian Planning Commission.

wetland attribute characteristic or combination of characteristics which is valued by a group within society, but which does not necessarily provide a function or support a use.

wetland characteristic properties of a wetland which describe the area in the simplest and most objective possible terms (e.g. wetland size, species present, soil type, water quality). Characteristics, singly or in combination, give rise to benefits (existing or future) which may be functions, uses, or attributes of a wetland.

wetland function area area required to be protected to ensure the important functions and values of the wetland can be maintained.


wetland function aspect of a wetland that, potentially or actually, supports or protects a human activity or human property without being used directly.

wetland value measure or expression of worth placed by society on a particular function, use or attribute.

wetland vegetation vegetation which is adapted to inundated or waterlogged conditions that often forms overlapping zones along an elevational gradient from the deepest part of a wetland. Wetland vegetation is essential to the ecological functioning of a wetland (and includes fringing and riparian vegetation) (Balla, 1994)

wetland water body part of a wetland where there is an expression of open water.

WRC Water and Rivers Commission (now the DoE).



Yangebup Lake is located on North Lake Road and can be identified on the GeomorphicWetlands Swan Coastal Plain dataset (DoE) as unique feature identifier number 6602.

Appendix 3: Example of application of the guideline - Lake Yangebup

Figure 5: Yangebup Lake (Source: Former Department of Land Administration StreetExpress Directory, 2000)


Step 2 Identify wetland attributes, wetland management category and establish management objectives

Has a wetland management category been assigned?

Yes. Yangebup Lake is a conservation category wetland.

Are existing wetland values, processes, functions and attributes consistent with the assignedmanagement category?

Yes. Yangebup Lake is a first-tier recognised wetland. It is on the Interim List of theRegister of the National Estate, protected by the Environment Protection Biodiversity Conservation Act 1999 as it provides a location for JAMBA/CAMBA species. It is protected under the Swan Coastal Plain Lakes EPP (EPA 1992) and located within Bush Forever Site 256) (Government of WA, 2000b). It also is reserved for Parks and Recreation and managed by theDepartment of Conservation and Land Management (CALM) as part of Beeliar Regional Park.

The review of the justification for the high management category identified the following keyvalues, processes and attributes for Yangebup Lake:

(a) high habitat diversity and wide representation of ecological communities (including upland communities);

(b) part of regional conservation/wildlife park;

(c) part of significant regional wetland system;

(d) part of regionally significant contiguous bushland/wetland linkage and wildlifecorridor (Greenways 78 and 81);

(e) supports wetland fringing vegetation;

(f) recognised migratory bird (as protected under JAMBA/CAMBA) habitat/breeding ground;

(g) important permanent water body for ducks (second highest recording of some species of 300 wetlands surveyed);

(h) supports a wide range of macroinvertebrate fauna;

(i) provides habitat and/or refuge for a range of frogs, reptiles (including the long-necked tortoise), birds and mammals that would not be there if a wetland was not present;

(j) significance to Aboriginal culture;

(k) entered on the Interim List of the Register of the National Estate;

(l) visual amenity of open water; and

(m) maintaining processes essential for retaining wilderness condition, which contributes to its landscape value.


The key attributes critical to the conservation category management objective of “to preservewetland (natural) attributes and functions” are points (a), (e), (f), (g), (i) and (j). These are theattributes that are critical to the determination of the extent of the boundary of the wetlandfunction area and the appropriate separation requirement.

The lake also retains nutrients from a nearby wool-scouring settling pond, performing afiltration function for local groundwater. This attribute is in conflict with the wetland’s highconservation status and the CALM management objective.

The information sources used to identify the above attributes include the justification forprotection of the area as a Bush Forever Site and the draft Beeliar Regional ParkManagement Plan (CALM, 2001) which identifies important attributes to be protected.

Step 3 Define wetland function area

Where practicable, the wetland function area is the area required to support the attributes ofthe wetland (see table 12). In the case of Yangebup Lake, the wetland function area shouldcontain at least the entirety of wetland vegetation plus all remnant upland vegetationcommunities abutting the wetland vegetation in Bush Forever site 256, to ensure themaintenance of all ecological communities associated with the wetland. Remnant vegetationareas within the Bush Forever site separated from the wetland vegetation by completelydegraded areas (>50 m wide) containing no native species are excluded from the wetlandfunction area as they are effectively isolated from the wetland and also are not part of awetland-upland continuum associated with the wetland.

As Yangebup Lake is part of a regional wetland system and due to the close proximity of awetland both to the north and south of the lake, the wetland function area practically extendsto link with wetland function areas of these two wetlands, Little Rush Lake and The Kogalups(North and South Kogalup Lake). The definition of the wetland function area boundary toassess setbacks from Yangebup Lake is relevant to only the west and east of the lake. Thepresence of developed residential and industrial land immediately west and east of the BushForever site boundary means the wetland function area does not extend further in thesedirections outside that boundary.

If the areas to the west and east of the lake were not developed, the wetland function areawould extend to a limit defined by the average range of dependent fauna associated withthe wetland (attribute (i)). The lake is inhabited by long-necked tortoises, which are known tomove from the wetland to lay eggs. Typically they roam between 50 and 200 m, but havebeen known to move as far as 500 m, from water bodies (WRC 2000, Bamford pers. comm.2002).

The wetland function area therefore should extend at least 200 m from the wetlandvegetation around Yangebup Lake, as this is an ecological requirement of a speciesdependent on the lake. This would be the case for any conservation category wetland thatsupports long-necked tortoises under this framework. However, because of the existingresidential and industrial development around Lake Yangebup, the wetland function area


cannot be realised. The wetland function area reaches its optimum extent in some areas, butfor the most part, is restricted by pre-existing development. The wetland function areatherefore corresponds to the wetland entity as mapped by Hill et al. 1996 (see Figure 5).

Attribute Requirement tosupport attribute,for the purpose ofdefining thewetland functionarea


Keythreateningprocesses

Role of separation

High habitatdiversity andwiderepresentationof ecologicalcommunities(includinguplandcommunities)

Maintainrepresentation of allidentified ecologicalcommunitiesassociated withwetland, to includeupland communitiesabutting wetlandvegetation zone

All remnantvegetation withinBush Forever siteboundary abuttingwetland vegetationin continuum.(excludescompletelydegraded areasand vegetationbeyond them)



• Can provide indirectsupport for wetland functionarea) through hydrologicaland terrestrial processes(eg external origin ofresources)

Part ofregionalconservation/wildlife park

Support attributesconsistent withmanagementobjectives

N/A • Alteration tothe waterregime


• Inappropriaterecreationaluse


As above



Boundary ofwetland asmappedGeomorphicWetland SwanCoastal PlainDataset (DoE)



• Can link adjacent wetlandseparation areas


• Can provide indirectsupport for wetland functionarea) through hydrologicaland terrestrial processes(eg external origin ofresources)

Part ofregionallysignificantcontiguousbushland/wetlandlinkage andwildlifecorridor(Greenways78 and 81)

Maintain bushlandlinks north, southand east of wetland

Providingconnection withbushland to north,south, and east


As above

Table 12: Requirements to support significant attributes of Yangebup Lake





Role of separation

Supportswetlandfringingvegetation

Maintain areascontaining emergentwetland species

Boundary ofwetland asmappedGeomorphicWetland SwanCoastal PlainDataset (DoE)





• Can provide indirectsupport for wetland functionarea) through hydrologicaland terrestrial processes(eg. external origin ofresources)

Recognisedmigratory bird(protectedunder JAMBA/CAMBA)habitat/breedingground

Maintain areas ofopen water,seasonallyinundated areasused for breedingand other areas ofvegetation likely tobe used by species

Boundary ofwetland asmapped by Hill etal (1996) plussurroundingvegetated areasknown to be usedby birds




As above

Importantpermanentwater body forducks (secondhighestrecording ofsome speciesof 300wetlandssurveyed)


Boundary ofwetland asmapped byGeomorphicWetland SwanCoastal PlainDataset (DoE) plussurroundingvegetated areasknown to be usedby birds




As above

Supports awide range ofmacroinverteb-rate fauna

Maintain naturalwater level





As above

Table 12: Requirements to support significant attributes of Yangebup Lake (continued)

Potentiallyprovideshabitat and/orrefuge for arange of frogs,reptiles(includingtortoise), birds,and mammals,that would nototherwise bethere if awetland wasnot present(associatedfauna)

Maintain all areas onwhich associatedfauna aredependent, suchthat localrepresentation is notaffected.Long-neckedtortoise is assumedto require greatestdistance fromwetland (200 m)(see text)

Extending fromwetland to averageknown extent offoraging/ use ofassociated fauna





As above





Role of separation

Significance toAboriginalculture

Maintain naturalstate of wetland,particularly area ofinundation

Boundary ofwetland asmapped byGeomorphicWetland SwanCoastal PlainDataset (DoE)



• Can add to as well asmaintain features of wetlandfunction area




Entered on theinterim list ofthe Register ofNational estate

All of above Bush Forever siteboundary






• Can provide indirectsupport for wetland functionarea through hydrologicaland terrestrial processes(eg external origin ofresources)

Visual amenityof open water

Maintain acceptedwater levels





Maintainingprocessesessential toretainwildernesscondition,whichcontributes toits landscapevalue

All of above Wetland functionarea (as definedfrom amassingareas describedabove)







Table 12: Requirements to support significant attributes of Yangebup Lake (continued)

Filtering forwool-scouringsettling pondeffluentmoving intogroundwater –lake serves toretain nutrientsand buffereffect on localgroundwater

Ensure rate ofeffluent flow towetland does notexceed ability ofwetland to filter outcontaminants fromgroundwater(filtering function ofwetland willdecrease waterquality and is likelyto affect naturalother naturalattributes)

Area withingroundwatercatchment zone ofwool-scouringsettling ponds



• Vegetation interception anduse of water in surface andsubsurface flow

• Can suppress watertableslocally


• Role redundant wherepiped discharge intowetland occurs

(Source: Welker Environmental Consultancy, 2002).



The threatening processes for each attribute were considered and are listed in table 12above. Processes that potentially could threaten the significant attributes of this wetlandwere identified based on consideration of the environmental risks of the surrounding parksand recreation reserve and residential and industrial land uses. Table 6 was used to aid thisassessment. The presence of three drains discharging directly into the wetland is a keyconsideration in managing wetland water quality.

The threatening processes requiring separation and/or management for Yangebup Lake are:• alteration to the water regime;• habitat modification;• inappropriate recreational use; and• diminished water quality.


The role of separation (ie distance and management) for each attribute was identified basedon consideration of tables 4 and 7. The role of separation for each attribute is listed in table 12.


The recommended separation distances for this management category are outlined in table 8.

The following separation measures (ie. distance and management) should be implementedfor Yangebup Lake to maintain condition consistent with its management objective:

• 100 m from wetland function area to urban and park areas to prevent weed infestation;

• Provision of 6 m to 50 m firebreak at and within separation requirement. (Note: DoE is unlikely to support firebreaks that need to be placed within the separation area if it requires significant clearing of native vegetation);

• ≥100 m from wetland function area to urban area to minimise edge effects;• ≥ 50 m from wetland function area to urban area to improve aesthetics and

barrier from inappropriate recreational activities;• 20 m to 100 m to prevent surface flow of suspended solids; and• drainage inflows eliminated or managed.

A separation distance of at least 100 m from the wetland function area would berecommended to meet the wetland’s management objective, together with elimination ormanagement of drainage inputs.

Other wetlands are located close to Lake Yangebup and the linking of separation areas andwetland functions also could be considered.


Step 7 Apply separation requirement to proposal and assess ability of separation to achieve management objective

Existing development, which has prevented the desired wetland function area beingrealised, will prevent a suitable separation distance and management measures from beingimplemented to support the management category objective. Both the wetland function areaand the separation distance are inconsistent with the management category objective andthe consequence of this lack of adequate buffering has been long term degradation of thelake and loss of conservation value. Any proposal for development within the separationrequirement is unlikely to be acceptable and should be referred to the EPA.



South Lake is located south and west of North Lake Road, Bibra Lake, in the City ofCockburn and can be identified on the Geomorphic Wetlands Swan Coastal Plain dataset(DoE) as unique feature identifier numbers 6603 and 6605.

Step 2 Identify wetland attributes, wetland management category and establish management objectives

Has a Wetland Management Category been assigned?

Yes. South Lake is a resource enhancement category wetland.

Appendix 4: Example of application of the guideline - South Lake

Figure 6: South Lake (Source: Former Department of Land Administration StreetExpress Directory, 2000)



The lake is located in Beeliar Regional Park, manged by CALM and is identified as Bush Forever site 254. South Lake is an EPP lake and is part of System 6 area M93.It is entered in the Interim List of the Register of the National Estate and therefore subject to protection under the Federal Environment Protection and Biodiversity Conservation Act 1999.

South Lake is a small, shallow, permanent lake covered extensively by reed beds. Itis surrounded by a diversity of dense vegetation which provides a habitat for a widevariety of birds. In the open water, aquatic plants attract large wading birds. The lake is a popular bird feeding area and is used by large numbers of migratory waterbirds. The lake is likely to serve a role as a breeding habitat for waterbirds because of the presence of fringing vegetation such as rushes, sedges and paperbarks.

The area is reserved for parks and recreation. The lake is surrounded by paperbark/ banksia woodland and is in good to very good condition, although thereare some areas of severe localised disturbance.

Step 3 Define the wetland function area

Where practicable, the wetland function area is the area required to support the attributes ofthe wetland (table 13).

The South Lake wetland function area should incorporate all wetland vegetation plus allremnant upland vegetation bordering the wetland vegetation, to ensure the maintenance ofall ecological communities associated with the wetland. Remnant vegetation areasseparated from the wetland vegetation by degraded areas (>50 m wide) are excluded fromthe wetland function area as they are effectively isolated from the wetland and are not part ofa wetland-upland continuum associated with the wetland.

At its furthest point, the wetland function area extends over 300 m from the water body onthe eastern side of the lake. The vegetation on the western side is more disturbed anddegraded, leaving a wetland function area of about 40 m from the water body. Althoughupland vegetation in good condition adjoins the degraded area to the south-west, thewetland function area does not continue into this area as it is separate from the functioningof the wetland. This does not mean the vegetation does not possess conservation values inits own right; however.

It could be argued that the wetland function area be extended to connect with a smallerwetland directly north. This wetland; however, is separated from South Lake by North LakeRoad, which comprises a road and cleared road reserve of 50m wide. This distance isconsidered enough of a separation that the wetland function areas would not be contiguous;however, the buffer areas of the wetlands would overlap.





Role of separation

High habitatdiversity andrepresentationof ecologicalcommunities(includinguplandcommunities)

Maintainrepresentation of allidentified ecologicalcommunitiesassociated withwetland, to includeupland communitiesabutting wetlandvegetation zone

All remnantvegetation withinBush Forever siteboundary abuttingwetland vegetationin continuum.(excludescompletelydegraded areasand vegetationbeyond them)



• Reduces potential forcolonisation by exoticspecies and introduction ofexotic terrestrial fauna

Part ofregionalconservation/wildlife park

Support attributesconsistent withmanagementobjectives

N/A • All • Protection from directdisturbance or otherchange/impact to thewetland function area




Boundary ofwetland asmapped in theGeomorphicWetland SwanCoastal PlainDataset (DoE)



• Can link adjacent wetlandseparation areas



Supportswetlandfringingvegetation

Maintain areascontaining emergentwetland species







Table 13: Requirements to support significant attributes of South Lake

Waterbirdhabitat/breed-ing ground


Boundary ofwetland asmapped in theGeomorphicWetland SwanCoastal PlainDataset (DoE) plussurroundingvegetated areasknown to be usedby birds






Supports awide range ofmacroinverte-brate fauna












Role of separation

Provideshabitat and/orrefuge for arange of frogs,reptiles, birds,and mammals,that would nototherwise bethere if awetland wasnot present(Associatedfauna)

Maintain all areas onwhich associatedfauna aredependent, suchthat localrepresentation is notaffected. This isassumed to includecontiguous uplandvegetation

Extending out fromwetland to averageknown extent offoraging/utilisationof associated fauna

• All • Protection from directdisturbance or otherchange/impact to thewetland function area


Significanceto Aboriginalculture

Maintain naturalstate of wetland,particularly area ofinundation




• Can add to as well asmaintain features of wetlandfunction area



Entered on theInterim List ofthe Register ofthe NationalEstate

All of above Bush Forever siteboundary

• All • Protection from directdisturbance or otherchange/impact to thewetland function area


Visualamenity ofopen water

Maintain acceptedwater levels





Table 13: Requirements to support significant attributes of South Lake (repeated)



The threatening processes for each attribute were considered and are listed in table 13.Processes that could potentially threaten the significant attributes of this wetland wereidentified based on consideration of the environmental risks of the industrial zoned land tothe south and west, the urban land to the east and the surrounding parks and recreationreserve which is separated by the other regional roads reserve. Table 6 was used to aid thisassessment.

The threatening processes requiring separation and management for South Lake are:• alteration to the water regime;• habitat modification;• inappropriate recreational use; and• diminished water quality.


The role of separation (distance and/or management) for each attribute was identified basedon consideration of tables 4 and 7. The role of separation for each attribute is also listed intable 13.


The recommended separation for this management category is outlined in Table 9.

The following separation measures (distance and/or management) should be implementedfor South Lake to maintain a condition consistent with its management objective:

• regulation of groundwater abstraction as catchment management measure;• 50 m from wetland function area to industrial and urban areas to prevent

weed infestation;• 50 m in addition to the wetland function area to protect bird habitat;

provision of 6 m to 50 m firebreak at edge of separation requirement;• ≥ 50 m from wetland function area to industrial and urban areas to minimise

edge effects;• ≥ 50 m from wetland function area to urban area to improve aesthetics and

barrier from inappropriate recreational activities;• 20 m to 100 m to prevent surface flow of suspended solids; and• ensuring no drainage inflows from nearby industrial or residential areas.

A maximum separation distance of 100 m from the wetland function area is required to meetthe wetland’s management objective and to minimse impacts on the wetland associatedlargely with the proposed industrial area to the south.


Other wetlands are located close to South Lake and the linking of separation areas andwetland functions should be considered in the context of any further development in thearea.

Step 7 Apply separation requirement to proposal and assess ability of separation to achieve management objective

A buffer of 100 m from the boundary of the wetland function area can be achieved to thesouth and east of South Lake, as the land is part of Bush Forever site 254 and reserved forparks and recreation. Although the wetland water body directly abuts industrial zoned landto the west, the proposed subdivision of this land (Lot 502) by LandCorp intends to include abuffer of at least 150 m from the water body. As the vegetation on this side is less than 50 mwide, this proposed buffer should be sufficient to retain wetland function.

The only questionable area is to the north, where a section of the buffer contains North LakeRoad. As the area adjacent is reserved for parks and recreation, it is considered thatalthough the road may be a barrier to large fauna movement, this is not seen as critical tothe maintenance of the significant functions of the wetland. Accordingly, the imposition of a100 m buffer around South Lake can be achieved and will meet the management objectiveof the wetland.



Stillwater Gardens Lake is located on Berrigan and South Lake Drives and can be identifiedon the Geomorphic Wetlands Swan Coastal Plain dataset (DoE) as unique feature identifiernumber 6523.

Step 2 Identify wetland attributes, wetland management category and establish management objective

Has a Wetland Management Category been assigned?

Yes. Stillwater Gardens Lake is a multiple use category wetland.

Appendix 5 Example of application of the guideline - Stillwater Gardens Lake

Figure 7: Stillwater Gardens Lake Source: Former Department of Land Administration StreetExpress 2000)



Yes. The lake is located in open parkland in the suburb of South Lake and categorised for multiple use as described by Hill et al (1996). It is under the management of the City of Cockburn and is not considered to possess any significant conservation values (City of Cockburn, pers. comm. 2002). It is zoned urban and is not protected. The lake is surrounded by reticulated grassed parkland used for recreational activities such as walking, jogging, picnics etc.

The lake represents a surface expression of the groundwater table in a low lying area and is likely to act as a local discharge area and help to maintain low groundwater levels in surrounding residential areas. Some stormwater drainage from surrounding roads is diverted to the lake and hence the lake has some function for local drainage.

As the lake is a permanent open body of water, however small, it is likely thatsome duck species frequent the lake. The lake is unlikely to serve any role asbreeding habitat for waterbirds because of the absence of fringing vegetation such as rushes/sedges/ paperbarks. The lake is not considered tosupport any significant flora or fauna values.

Step 3 Define the wetland function area

The wetland function area of Stillwater Gardens Lake is defined by the area within the highwater level mark for the wetland as determined from the requirements for significantattributes (table 14).


Processes that potentially could threaten the attributes of this wetland were identified basedon consideration of the environmental risks of the surrounding urban zoning and near byparks and recreation reserve. Table 6 was used to aid this assessment.

The threatening processes for each attribute were considered (table 13). The relevantattributes identified are:

• alteration to the water regime• diminished water quality





Role of separation

Frequented byduck andpossibly otherwaterbirdspecies






Visualamenity ofopen water

Maintain seasonalwater level

Areas seasonallyinundated




Local drainage Access andsufficient basin sizeto prevent floodingof surrounding area

Dependent onamount of water tobe received


• No role

Table 14: Requirements to support significant attributes of Stillwater Gardens Lake


The role of separation for each attribute was identified based on consideration of tables 6and 7. The role of separation for each attribute is listed in table 14.


The recommended separation (distances and/or management) for this managementcategory are outlined in table 10.

However, as no separation is required to manage the potential for alteration to the waterregime, no separation area beyond the wetland function area is required. Proposals forappropriate development outside the wetland function area of the wetland should meet themanagement objective for a multiple use wetland.

Water quality and groundwater abstractions in the catchment will still need to be managed;however, to ensure no impact on the values, functions and attributes of the wetland.

Other wetlands are located close to Stillwater Gardens Lake. The potential to link theseparation areas and wetland function areas could be considered.

This has been released to seek public comment on the information in the draft guideline. All aspects of the

guideline will be re-assessed prior to being finalised.

Every submission received will be acknowledged in writing and will be considered in the review process. All

submissions will be treated in the strictest confidence.

When making a submission, it is very helpful to:

• clearly state your opinion and the reasons for your opinion

• if possible, outline possible alternatives or solutions to your area of interest

• if possible, include the section or page number which relates to your area of interest

• provide any additional information to support your comments.

A public submission form is included overleaf for your convenience, which can be posted free of charge. If

you prefer to make a comment in an alternative format, please remember to include the relevant details as

outlined on the submission form.

The closing date for submissions is Friday 14 April 2006

You can send your submissions free of charge to:

Guideline for the Determination of Wetland Buffer RequirementsWestern Australian Planning CommissionAlbert Facey House469 Wellington StreetReply Paid 80014PERTH WA 6000

If you would like more information on making a submission, please contact:Manager environmental planning,Tel: (08) 9264 7777Fax (08) 9264 7566email: [email protected]

We look forward to receiving your submission.

Public submissions for the draft Guideline for the Determinationof Wetland Buffer Requirements

Public submission formDraft Guideline for the Determination of Wetland Buffer Requirements

1 Name: . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

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2 Organisation (if relevant): . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

3 Address: . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

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4. Interest: . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

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(eg local resident, business operator)

I/we would like to make the following comments on the draft Guideline for the Determination of WetlandBuffer Requirements and would like them to be considered in the preparation of the final document

Comments: . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

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Guideline for the Determination of Wetland Buffer Requirements

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