hobsons bay city council stormwater management plan volume iii (of 3 volumes…€¦ · ·...

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Hobsons Bay City Council Stormwater Management

Plan Volume III (of 3 Volumes)

Appendices

Prepared For: Hobsons Bay City Council

Prepared By: WBM Oceanics Australia

Offices

Brisbane Denver

Karratha Melbourne

Morwell Newcastle

Sydney Vancouver


DOCUMENT CONTROL SHEET

Document: R.M6790.004.00.HBCC_SWMP_VOL3.doc

Title: City of Hobsons Bay Stormwater Quality Management Plan Volume III Appendices

Project Manager: Kevin Wood

Author: Joel Leister, Kevin Wood

Client: Hobsons Bay City Council

Client Contact: Andrew Shannon

Client Reference:

WBM Oceanics Australia Melbourne Office: Level 5, 99 King Street MELBOURNE VIC 3000 Australia PO Box 604 Collins Street West VIC 8007 Telephone (03) 9614 6400 Facsimile (03) 9614 6966 www.wbmpl.com.au ACN 010 830 421

Synopsis: This report constitutes the third volume of the Stormwater Management Plan developed for the Hobsons Bay City Council. This report provides details of Appendices relating to Volume II.

REVISION/CHECKING HISTORY

REVISION

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CONTENTS I


CONTENTS

Contents i List of Tables ii List of Figures iii

1 INTRODUCTION 1

APPENDIX A: PROJECT WORKING GROUP DISCUSSION PAPERS A-1

APPENDIX B: PROJECT WORKING GROUP MEMBERS B-1

APPENDIX C: PRIORITY ISSUES PAPER C-1

APPENDIX D: RISK ANALYSIS RESULTS D-1

APPENDIX E: RISK MANAGEMENT ACTION SCREENING E-1

APPENDIX F: MANAGEMENT ACTION OPPORTUNITIES F-1

APPENDIX G: REACTIVE STRATEGY COST BENEFIT ASSESSMENT G-1

LIST OF TABLES II


LIST OF TABLES Table E-1 Management Element Screening Results for Risk Strategy 1 E-2 Table E-2 Management Element Screening Results for Risk Strategy 2 E-3 Table E-3 Management Element Screening Results for Risk Strategy 3 E-4 Table E-4 Management Element Screening Results for Risk Strategy 4 E-5 Table E-5 Management Element Screening Results for Risk Strategy 5 E-6 Table E-6 Management Element Screening Results for Risk Strategy 6 E-7 Table E-7 Management Element Screening Results for Risk Strategy 7 E-8 Table E-8 Management Element Screening Results for Risk Strategy 8 E-9 Table F-1 Priority Risk Issue 1, Management Action Opportunities F-2 Table F-2 Priority Risk Issue 2, Management Action Opportunities F-5 Table F-3 Priority Risk Issue 3, Management Action Opportunities F-6 Table F-4 Priority Risk Issue 4, Management Action Opportunities F-8 Table F-5 Priority Risk Issue 5, Management Action Opportunities F-10 Table F-6 Priority Risk Issue 6, Management Action Opportunities F-11 Table F-7 Priority Risk Issue 7, Management Action Opportunities F-12 Table F-8 Priority Risk Issue 8, Management Action Opportunities F-13 Table G-1 Strategy Formulation for Stormwater Risk Management Strategy 1 G-2 Table G-2 Strategy Formulation for Stormwater Risk Management Strategy 2 G-4 Table G-3 Strategy Formulation for Stormwater Risk Management Strategy 3 G-6 Table G-4 Strategy Formulation for Stormwater Risk Management Strategy 4 G-8 Table G-5 Strategy Formulation for Stormwater Risk Management Strategy 5 G-10 Table G-6 Strategy Formulation for Stormwater Risk Management Strategy 6 G-12 Table G-7 Strategy Formulation for Stormwater Risk Management Strategy 7 G-14 Table G-8 Strategy Formulation for Stormwater Risk Management Strategy 8 G-16

LIST OF FIGURES III


LIST OF FIGURES

Figure G-1 Strategy Formulation for Stormwater Risk Management Strategy 1 G-3 Figure G-2 Strategy Formulation for Stormwater Risk Management Strategy 2 G-5 Figure G-3 Strategy Formulation for Stormwater Risk Management Strategy 3 G-7 Figure G-4 Strategy Formulation for Stormwater Risk Management Strategy 4 G-9 Figure G-5 Strategy Formulation for Stormwater Risk Management Strategy 5 G-11 Figure G-6 Strategy Formulation for Stormwater Risk Management Strategy 6 G-13 Figure G-7 Strategy Formulation for Stormwater Risk Management Strategy 7 G-15 Figure G-8 Strategy Formulation for Stormwater Risk Management Strategy G-17

INTRODUCTION 1


1 INTRODUCTION

WBM Oceanics Australia was commissioned by Hobsons Bay City Council to review the existing Stormwater Management Plan (SWMP) and develop a new plan. This new SWMP takes into account changes in the catchment, the priority risks and management at Hobson Bay City Council. The SWMP has been developed to guide Council in improving the environmental management of stormwater throughout the municipality.

The SWMP provides a framework for integrating stormwater management as part of Council’s existing management and planning activities. In this regard, the SWMP is intended to provide the basis for an ongoing process that is aimed at protecting and enhancing receiving environmental values and beneficial uses that are currently threatened by stormwater runoff. The SWMP also provides a basis by which efforts to manage stormwater can be planned and budgeted.

The Stormwater Management Plan has been prepared in 3 volumes with this report constituting Volume III of the Stormwater Management Plan. Volume III contains Appendices with data and detailed information to accompanying Volume II.

Information presented in Volumes I and II of the plan include:

• Volume I – this is an executive summary document which provides a précis of the overall Stormwater Management Plan.

• Volume II – this document details the approach adopted in developing the Plan, recommendations aimed at responding to existing threats to environmental values and suggested improvement to Council’s management framework to limit the future occurrence of stormwater threats.

PROJECT WORKING GROUP DISCUSSION PAPER 1 A-1


APPENDIX A: PROJECT WORKING GROUP DISCUSSION PAPER 1

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Hobsons Bay Stormwater

Management Plan

Discussion Paper 1 – Study Overview and Current SWMP

Status and Direction


Prepared By: WBM Engineering and Environmental Consultants

Offices

Brisbane Denver

Karratha Melbourne

Morwell Newcastle

Sydney Vancouver



Document: R.M6790.001.00.DiscussionPaper1.doc

Title: Hobsons Bay Stormwater Management Plan Discussion Paper 1 -


Author: Belinda Lovell


Client Contact: Sam Sampanthar

Client Reference:

WBM Engineering and Environmental Consultants Melbourne Office: Level 5, 99 King Street MELBOURNE VIC 3000 Australia PO Box 604 Collins Street West VIC 8007 Telephone (03) 8620 6100 Facsimile (03) 8620 6105 www.wbmpl.com.au ABN 54 010 830 421 007

Synopsis: This discussion paper outlines the proposed framework and objectives of the SWMP. It also provides a brief overview of available information and background issues that are relevant to stormwater management in Council.


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CONTENTS I


CONTENTS

1 INTRODUCTION 1-1

1.1 What is Stormwater? 1-1 1.2 What is Stormwater Management? 1-1 1.3 Background – Why is a SWMP being reviewed and updated? 1-2 1.4 Major Outcomes of this SWMP 1-3

2 BACKGROUND INFORMATION REVIEW 2-4

2.1 Summary of information 2-4 2.2 GIS Data 2-4 2.3 Commentary on Previous Stormwater Management Planning Process 2-5 2.4 Management Action Implementation and Major Achievements 2-5 2.5 Framework – How will the SWMP be developed? 2-6 2.6 Catchment Definition 2-8 2.7 Project Working Group Involvement 2-9

2.7.1 Project Working Group Meeting 1 Objectives – Identifying Stormwater Issues and Strengths 2-10 2.7.2 Project Working Group 1 Meeting Agenda 2-10

LIST OF FIGURES

Figure 1-1 Stormwater improvement tools summarised into basic categories 1-2 Figure 2-1 Stormwater Management Planning Process 2-6 Figure 2-2 Flow chart of key tasks to be undertaken 2-7 Figure 2-3 Project Schedule 2-8

LIST OF TABLES

Table 2-1 Key Sources of Information Considered for the Initial Review 2-4 Table 2-2 Reference Group Meetings 2-9

INTRODUCTION 1-1


1 INTRODUCTION

Hobsons Bay City Council has embarked upon a process to review and revise its Stormwater Management Plan (SWMP), which was prepared in 1999. The review is being undertaken in order to:

• Ensure Council’s approach to stormwater management addresses the priorities of the Hobson’s Bay community;

• Identify gaps in Council’s stormwater management, particularly in relation to new and emerging management techniques.

Council has appointed environmental consultants WBM to undertake the review and prepare a new Plan with assistance and input from key stakeholders who are involved in environment and land management activities in the City. Within Council, the development of the SWMP is being co-ordinated by Andrew Shannon.

1.1 What is Stormwater?

Stormwater is runoff that occurs during and following rainfall. This runoff is often contaminated as it washes pollutants off the surfaces it falls onto. After high rainfall events, large volumes of water enter rivers and creeks, transporting sediment, nutrients, toxic chemicals, herbicides, pesticides, oils and grease, animal waste and sewage overflows. Some heavy metals, especially zinc, lead and copper, are now widespread in stormwater.

Stormwater is largely separate from the sewerage or waste water system, and has generally not been treated. Stormwater systems are connected directly to streams and other waterways and as a result, have an immediate impact on the quality of these receiving waters. In some cases, litter traps or wetlands, usually located at the end of the underground pipe network, filter it, but in most cases it flows directly to our bay, creeks and rivers. Minimising the pollution from stormwater requires everyone in a catchment to be careful to ensure that only rainwater enters the stormwater system.

Modification of the natural characteristics of the City of Hobsons Bay, through processes such as land use change and development, has had a significant impact on the nature of stormwater runoff. Urbanisation creates large areas of impermeable surfaces, particularly roads, car parks and roof areas. This has resulted in significant changes to catchment hydrology, with reduced times of concentration and greater frequency of discharge and increased flows as a result of storm events.

The City of Hobson Bay’s stormwater system is composed of modified waterways, constructed drains, lakes and retarding basins and has been developed to minimise the threat of flooding. Traditional drainage design focussed on the efficient conveyance of stormwater from where it could pose a risk to life or property.

1.2 What is Stormwater Management?

Stormwater management is concerned with the development and implementation of a range of strategies to minimise the impacts of stormwater pollution and to protect the values of the receiving environment. These strategies can include a range of site-specific structural and non-structural

INTRODUCTION 1-2


measures as well as plans, policies and procedures aimed at managing activities that could potentially result in stormwater pollution. These tools can be grouped into a number of basic categories, which all contribute to stormwater quality improvements (Figure 1-1).

Stormwater Management

Planning Framework Documentation

Education

•WSUD in new and in-fill developments

•Retrofitting

•Address hot-spots

On-ground implementation

•Policies

•Local Laws

•Procedures

•Contractual Requirements

•Enforcement

•Community Awareness

•Target hot-spots

•Schools Education

•Council Contractors and Staff

•Reward success

Figure 1-1 Stormwater improvement tools summarised into basic categories

Each of the above categories plays a role in the potential improvements that can be achieved by Councils. Each tool, on its own, is not as effective as in combination with others.

1.3 Background – Why is a SWMP being reviewed and updated?

Urban stormwater has been recognised for many years as a significant contributor of pollution to our waterways, resulting in reduced environmental value and public amenity. To offset the impact of urban development on stormwater quality, a range of structural and non-structural catchment management techniques are available. To achieve best practice in the environmental management of urban stormwater, it is important that catchment management activities are guided by a Stormwater Management Plan. Stormwater Management Plans identify actions that improve the environmental management of urban stormwater and protect the environmental values and beneficial uses of receiving waters.

Hobsons Bay’s SWMP was completed in 1999 and employed the best knowledge and techniques available at that time. Since then there have been a number of developments in stormwater management in Victoria, the most significant being:

o A change in focus from ‘end-of-pipe’ or treatment measures to a greater emphasis on source control and behavioural change through education. This is reflected in the State Environment Protection Policy Waters of Victoria.

o An increased interest in utilisation of stormwater as a resource, as part of Integrated Water Cycle Management. This is reflected in Victorian Government policy related to water, through the creation of the Victorian Stormwater and Urban Water Conservation Fund, and in the proposal for Sustainable Water Use Plans and water cycle planning at a municipal level.

INTRODUCTION 1-3


o There has been significant progress in the availability of tools for the application of Water Sensitive Urban Design (WSUD) in new urban development and these can now be realistically incorporated into the municipal planning framework. This is reflected in the ‘Clean Stormwater Planning Framework’ developed by the Association of Bayside Municipalities, which provides a framework and designs for integrating WSUD into developments and a mechanism for water quality offsetting within the catchment. In addition the MUSIC software has been developed and is being applied to the evaluation of stormwater treatment and WSUD schemes for individual site elements right through to whole catchments.

o There is additional information on the performance and life cycle costs associated with a range of stormwater treatment measures to assist in the refinement or development of efficient and cost effective stormwater strategies.

o The increased emphasis on higher urban densities at appropriate growth centres, as provided for in Melbourne 2030 increases the requirement for careful planing of stormwater to manage increasing runoff.

Review and revision of the Hobsons Bay SWMP at this time provides the opportunity to identify additional stormwater management measures that can be implemented, particularly in the context of new and emerging stormwater management techniques. It also provides the opportunity to design a new approach to integrated stormwater conservation and management that reflects the priorities of the Hobson’s Bay community.

1.4 Major Outcomes of this SWMP

The revised SWMP will include a number of outcomes that are targeted to assist Council to improve its management activities and respond to priority threats that may impact on environmental and amenity values. Key recommendations or outcomes of the SWMP will include:

• Specific Stormwater Management Strategies that aim to respond to priority risks in the municipality; and

• Recommendations for improvement of Council’s Management Framework to prevent stormwater degradation before it occurs.

The SWMP will also provide details of an implementation and review program so that Council can integrate the Plan within its existing frameworks and revise and refine the plan in the future.

BACKGROUND INFORMATION REVIEW 2-4


2 BACKGROUND INFORMATION REVIEW

2.1 Summary of information

An important part of the study involves the collection and review of available information and data that relates to existing management practices and programs that contribute to stormwater management in Hobsons Bay City Council (including the existing SWMP). Key sources of literature considered in this initial review are presented in Table 2-1.

Table 2-1 Key Sources of Information Considered for the Initial Review Author Date Title City of Hobsons Bay 1997 Charting Out Future The Hobsons Bay Strategy AWT Victoria and TBA Planners Mar-1999 Stormwater Management Plan for City of Hobsons Bay City of Hobsons Bay Hobsons Bay Environment Plan

Maribyrnong City Council 2002 A Neighbourhood Environment Improvement Plan for Lower Stony Creek Corridor

AWT and Lloyd Environmental Consulting Nov-2000 Stormwater Management Plan Review AWT and Lloyd Environmental Consultants

November 2000

Stormwater Management –Structural Treatment Recommendations

PPK Environment & Infrastructure Jul-2002 Water Sensitive Urban Design Guidelines PPK Environment & Infrastructure Aug-2002 Site Management Plan Guidelines PPK Environment & Infrastructure Jun-2002

Catchment Development Impact Project -Statutory Responses Report

City of Hobsons Bay Nov-2002 Hobsons Bay Building Code of Practice Association of Bayside Municipalities 2004

Delivering Water Sensitive Urban Design: Final Report of Clean Stormwater – A Planning Framework

Melbourne Water 1999 -2004 Water quality data for waterways

Environment Protection Authority Victoria

1999 - 2004 Bay Beaches Water Quality Data

2.2 GIS Data

To undertake the study, Geospatial Information System (GIS) data was obtained from Council and Melbourne Water, and was subsequently incorporated into a MapInfo GIS database. The following list outlines the data obtained and its source:

• Land use zones and planning overlays;

• Road layouts;

• Municipal boundary; and

• Local drainage system information.

In addition to digital data, the Council also provided information identifying the location and details of existing and proposed structural treatment devices.



2.3 Commentary on Previous Stormwater Management Planning Process

The process for development of the existing Stormwater Management Plan differed to some degree from that applied to SWMPs developed in more recent years. For example approaches now advocated include:

o definition of receiving waters and identification of the values associated with these;

o a clear emphasis on Council’s management framework in developing improvement strategies, and

o a distinction between proactive and reactive management strategies.

However, there were also, of course a number of similarities, the most important being:

o Examination of land uses, activities and municipal management measures and their relative contributions to stormwater issues and management;

o Identification of values, threats, risks and issues;

o Close involvement of key stakeholders in the development of the Plan.

The values, threats and issues identified in the SWMP will be considered in the context of current variables during the next Phase of the project, and at the next meeting of the Reference Group.

2.4 Management Action Implementation and Major Achievements

There were a number of strategies and actions recommended in the existing SWMP. The extent and success of their implementation will be evaluated in Phase 2 of the project. They will also be evaluated in the context of the on-going validity and relevance during Phase 3.

Council has undertaken a number of activities since the Plan was completed in 1999, specifically:

o Preparation of planning guidelines and responses to stormwater issues in conjunction with the adjacent municipalities of Maribyrnong, Wyndham and Maribyrnong, including:

o Building site management guidelines

o Planning Scheme amendments covering stormwater

o Planning permit requirements

o WSUD guidelines

o Reviewing structural treatment opportunities and needs, and installing a number of GPTs and wetlands on drainage lines;

o Introducing covered recycling collection bins;



o Street sweeping and beach cleaning

o Community education;

o Establishment of bylaws covering dog littering and provision of dog litter collection bags at off-leash areas.

There have also been pollution control activities undertaken in conjunction with the EPA involving local industry, particularly the management of stormwater on some major industrial sites and the treatment of contaminated groundwater.

A more comprehensive review of the extent of implementation of actions in the existing plan will also be completed in Phase 2.

2.5 Framework – How will the SWMP be developed?

The adopted approach for reviewing and revising the SWMP generally reflects the process described in the Urban Stormwater Best Practice Environmental Management (BPEM) Guidelines (revised Chapter 3). These guidelines describe a logical, staged approach involving four phases. The approach has been modified to reflect that this is a review of an existing Plan, and provides for planning for stormwater as a water resource within the municipality. Figure 2-1 presents the process to be undertaken, which includes the following four distinct phases:

• Phase 1 Preliminary Activities;

• Phase 2 Risk Management;

• Phase 3 Revision of Stormwater Management Plan; and

• Phase 4 Finalise the Stormwater Management Plan.

The application of this process will specifically consider stormwater management in terms of current stormwater risks and Council’s planning and management framework.

Identify LocalStormwater

ManagementIssues & Strengths

ManagementFramework Review

Preliminary Activities

ValuesAssessment

Collate andReview Available

Data

StormwaterThreats

RiskAssessment

StormwaterManagement

Strategies

ManagementFrameworkStrategies

REA

CTI

VEPR

OAC

TIVE

RISK Management Management PlanDevelopment

Phase 2Phase 1 Phase 3

PriorityManagement

Issues

SubmitStormwater

ManagementPlan

FinaliseStormwater

Management Plan

Phase 4

Figure 2-1 Stormwater Management Planning Process



The detailed process for review and revision of the Hobsons Bay SWMP is shown below in Figure 2-2, and the timing in Figure 2-3.

Figure 2-2 Flow chart of key tasks to be undertaken

Project Inception

Collate and reviewavailable information

PRGWorkshop 1

Review of SWMP's currentStatus and Direction

Define StudySubcatchments

Review of Threats andValues

Risk Assessment

Priority ManagementIssues Paper

Issues Paper ApprovalHobsons Bay City Council



Strategies

Implementation Framework

Submit Draft SWMP

Finalise SWMP

Pha

se 1

Phas

e 2

Pha

se 3

Phas

e 4

PRGWorkshop 2

PRGWorkshop 3

PRGMeeting

Hobsons Bay City Council



Figure 2-3 Project Schedule

2.6 Catchment Definition

To aid in the development of management strategies, the municipality was divided into catchments. The catchments were defined via hydrologic boundaries, local drainage and land use zoning. In affect, these catchment boundaries are based on the drainage system that serves the area, or the water body to which the area drains. Using this approach, 5 separate catchments were defined:

o Skeleton Creek

o Laverton Creek

o Port Phillip Bay (Altona)

o Cherry Creek

o Kororoit Creek

o Williamstown Range Lake

o Williamstown/Newport Beaches

o Stony Creek.

These are shown at the end of the document.

Within these catchments there are a number of smaller drainage systems, based on the constructed drainage network; that is street and precinct drains. These may drain to the major waterways or

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Phase 1 – Preliminary Activities

Project Reference Group Inception Meeting

Collation and Review of Available Information/Data

GIS Setup and Development

Discussion Paper 1

Review of SWMPs Current Status and Direction

Project Working Group Workshop No. 1

Phase 2 - Risk Management

Preliminary Sub-Area Definition

Examination of Water Quality and Biological Data

Risk Assessment

Preparation of Priority Management Issues Paper (Discussion Paper 2)

Project Reference Group Meeting No. 2

Project Working Group Workshop No. 2

Confirmation of Issues Paper

Phase 3 - Development of Stormwater Management Plan

Review and Identify New Directions and Strategies

Development of Management Strategies

Preliminary Implementation Framework

Discussion Paper 3

Project Working Group Workshop No.3

Preliminary Draft Stormwater Management Plan

Phase 4 - Reporting

Project Reference Group Meeting No. 3

Presentation to Council and Project Reference Group

Finalisation of Stormwater Management Plan

Phase 4 - Project Management

LegendProject Reference Group MeetingsProject Working Group WorkshopsReview Periods

Key Project Tasks

Week Beginning



directly to Port Phillip Bay. The boundaries of these subcatchments and the direction of flow are also shown at the end of the document.

2.7 Project Working Group Involvement

A key component in the development of the SWMP is four Project Reference Group meetings conducted throughout the study. A discussion paper will precede each meeting. The proposed outcomes from these meetings are summarised in Table 2-2.

Table 2-2 Reference Group Meetings Meeting Number and Date Proposed Outcomes

1

2 June

• Ensure that PWG members have a clear understanding of the principles that relate to stormwater management, the approach being adopted as part of this project and their role in formulating the SWMP;

• Identify and discuss existing stormwater management strengths and values in the municipality and associated with the current SWMP;

• Identify and discuss key local and regional stormwater management issues of concern to PWG members; and

• Identify further information sources that were not revealed during earlier stages of the investigation.

2

23 June

• Present the outcomes of the values and threats assessment and discuss and review these.

• Present Risk Assessment results and compare with the issues the Project Reference Group believes are important.

• Inconsistencies will be discussed and alterations will be made to ratings ascribed against values and threats (where necessary).

• At this stage it may be appropriate to review the ranking of Priority Management Issues.

3

1 September

• Evaluate management options and formulate management strategies.

• At this stage of the project, the management strategies agreed by the PRG will provide a basis for the Draft Stormwater Management Plan.

4

20 October

• Discuss comments and feedback regarding the Preliminary Draft Stormwater Management Plan.

In addition to the four Project Reference Group meetings, the Group will be asked to provide comment on reporting at key stages in the development of the plan, these being:

• Review of the Priority Issues Paper

• Review of Draft Stormwater Management Plan

Andrew Shannon (Hobson Bay City Council’s Project Manager) will coordinate and consolidate all Reference Group comments at these stages and provide feedback via meetings with WBM to then be incorporated into the development of the plan.



2.7.1 Project Working Group Meeting 1 Objectives – Identifying Stormwater Issues and Strengths

A key outcome of Project Reference Group meeting one is the identification of existing management strengths (values) and issues relating to stormwater management. In preparation for the first meeting, Group members will be asked to consider existing management practices, strengths or values within Council relating to stormwater. Management strengths are positive actions that are being undertaken within Council, by Council staff and/or other organisations, to improve the quality of stormwater runoff. This may include an existing management practice such as street sweeping. Project Working Group members are also asked to consider key stormwater management issues. This will include current concerns that meeting members may have regarding stormwater pollution threats that inhibit effective stormwater management. During the meeting participants will be asked to contribute their thoughts on strengths and issues as part of a round table discussion. The results of these discussions will be recorded and used to focus the subsequent investigation of stormwater management within the municipality.

2.7.2 Project Working Group 1 Meeting Agenda

The workshop will commence with a presentation by the Project Team outlining the principals that relate to stormwater management, objectives of the project, the approach being adopted as part of the project and the role that stakeholders will play in developing the SWMP. Project Reference Group members will then be asked to participate in a session aimed at identifying existing stormwater management issues and strengths in the municipality and associated with the current SWMP.

The proposed agenda for the 1st Stakeholder Meeting is outlined as follows:

• Welcome and Introduction (Council staff and Study Team)

• Meeting Overview (Study Team)

• Summary of Project Objectives, Methodology and Outcomes (Study Team)

• Discussion of Stormwater Management Priority Issues (Study Team)

• Coffee and Tea Break

• Discussion of Existing Stormwater Management Initiatives and Values (PWG and Study Team)

• Discussion of Stormwater Management Priority Issues (PWG and Study Team)

• Meeting Summary and Close (Study Team)

PROJECT WORKING GROUP MEMBERS B-1


APPENDIX B: PROJECT WORKING GROUP MEMBERS

Name Organisation Division/Department

Jenny Brockman Laverton Secondary College

Nessie Hardy Local Resident/Friends Groups

Geoff Mitchelmore Friends of Lower Kororoit Creek

Judy Hindle Friends of Westona Wetlands

Mandy Bolton Environmental Protection Authority

Brian Cullen City West Water

Jake Moore Melbourne Water

Andrew Shannon Hobsons Bay City Council Team Leader, Parks and Environment

Matt Aquilina Hobsons Bay City Council Environment Officer

Chris Willard Hobson Bay City Council Manager, Statutory Planning

Allan Breasley Hobsons Bay City Council Team Leader, Design and Project Management (Engineering Services)

Steve Patralakis Hobsons Bay City Council Senior Road Engineer (Assets and Maintenance)

Louis Papageorgiou Hobsons Bay City Council Environmental Health Michelle Gooding Hobsons Bay City Council Parks Ranger Paul Thomas* Dow Chemical

* Paul was unable to attend meetings, however, made comments on all draft reports

PRIORITY ISSUES PAPER C-1


APPENDIX C: PRIORITY ISSUES PAPER

S:\M6790.KW.HOBSONS_BAY_SWMP\REPORT\PHASE 2 - PRIORITY MANAGEMENT ISSUES\R.M6790.002.01.HB_ISSUES_PAPER.DOC

Hobsons Bay City Council Stormwater Management

Plan Review Priority Issues Paper


Prepared By: WBM

Offices

Brisbane Denver

Karratha Melbourne

Morwell Newcastle

Sydney Vancouver



Document: R.M6790.002.00.HB_Issues_Paper.doc

Title: Hobsons Bay City Council Stormwater Management Plan Review Priority Issues Paper


Author: Joel Leister, Kevin Wood


Client Contact: Andrew Shannon

Client Reference:

WBM Melbourne Office: Level 5, 99 King Street MELBOURNE VIC 3000 Australia PO Box 604 Collins Street West VIC 8007 Telephone (03) 9614 6400 Facsimile (03) 9614 6966 www.wbmpl.com.au ACN 010 830 421

Synopsis: This report presents the issues paper for Hobsons Bay Stormwater Management Plan Review. The issues paper provides a summary of key stormwater management issues that have been identified through the course of the risk assessment process.


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CONTENTS I


CONTENTS Contents I List of Figures II List of Tables II

1 INTRODUCTION 1-1

2 SETTING THE SCENE 2-1

2.1 Hobsons Bay Catchments 2-6 2.2 Existing Stormwater Management Plan 2-9

3 STORMWATER MANAGEMENT ISSUES 3-1

3.1 Stormwater Risk Assessment 3-1 3.2 What are the Key Values? 3-2

3.2.1 Aquatic Habitat 3-3 3.2.2 Riparian Habitat 3-3 3.2.3 Faunal Habitat 3-3 3.2.4 Cultural Heritage 3-3 3.2.5 Recreation Amenity (swimming) 3-4 3.2.6 Visual/Landscape Amenity (including boating) 3-4 3.2.7 Flood Conveyance 3-4 3.2.8 Tourism 3-4 3.2.9 Receiving Waters 3-4

3.3 Values Assessment 3-4 3.4 What are the Key Stormwater Threats? 3-5

3.4.1 Definition of Threats 3-6 3.4.2 Assessment of Threats 3-9

3.5 Risks 3-13 3.6 Summary of Key Stormwater Risk Issues 3-15 3.7 Water Quality Data 3-16

4 BIBLIOGRAPHY 4-1

LIST OF FIGURES II


APPENDIX A: SUMMARY OF SCORES FOR CATCHMENT RISK ASSESSMENT A-1

APPENDIX B: RISK ANALYSIS RESULTS B-1

APPENDIX C: COMPARISON OF VALUES, THREATS AND RISKS IN THE 1999 PLAN AND THE CURRENT PLAN C-1

APPENDIX D: IMPLEMENTATION OF ACTIONS FROM THE 1999 SWMP D-1

LIST OF FIGURES

Figure 1-1 Stormwater Management Planning Process 1-1 Figure 2-1 Locality Plan of Hobson Bay City Council 2-3 Figure 2-2 Major Waterways of Hobsons Bay 2-4 Figure 2-3 Land Use Planning Codes in Hobsons Bay 2-5 Figure 2-4 Hobsons Bay Stormwater Catchments 2-7 Figure 2-5 Hobsons Bay Subcatchments and Drainage Routes 2-8 Figure 3-1 Risk Assessment 3-1 Figure 3-2 Water Quality Results 2000-2004 3-18

Figure A-1 Cheetham Wetlands A-1 Figure A-2 Residential and Commercial Runoff on Laverton Creek A-5 Figure A-3 Kororoit Creek in flood with Industry in the background A-15 Figure A-4 Williamstown Beach A-19 Figure A-5 Nelson Place in Williamstown A-23 Figure A-6 Stony Creek Backwash A-25

LIST OF TABLES

Table 2-1 Major Land Uses in Hobsons Bay 2-6 Table 3-1 Score System for Threats, Values and Sensitivity 3-2 Table 3-2 Value Types 3-2 Table 3-3 Summary of Values Assessment Error! Bookmark not defined. Table 3-4 Generic threats adopted for the Hobson Bay City Council 3-6 Table 3-5 Pollutant Impacts and Time Scales 3-8 Table 3-6 Summary of Threats Assessment 3-9

LIST OF TABLES III


Table 3-7 Priority Stormwater Risks in Hobson Bay City Council 3-13

Table A-1 Skeleton Creek Catchment Summary A-1 Table A-2 Laverton Creek Catchment Summary A-4 Table A-3 Port Phillip Bay (Altona) Catchment Summary A-7 Table A-4 Cherry Creek Catchment Summary A-11 Table A-5 Kororoit Creek Catchment Summary A-14 Table A-6 The Range Catchment Summary A-17 Table A-7 Williamstown/Altona Beaches Catchment Summary A-19 Table A-8 Williamstown/Newport Catchment Summary A-22 Table A-9 Stony Creek Catchment Summary A-25

Table C-1 Values Comparison of 1999 and 2005 Plans C-1

Table C-2 Threats Comparison of 1999 and 2005 Plans C-1

Table C-3 Risk Comparison of 1999 and 2005 Plans C-2

INTRODUCTION 1-1


1 INTRODUCTION

The State Government’s Victorian Stormwater Action Program (VSAP) was launched in June 2000 to assist local government and catchment managers with adoption of improved environmental practice for urban stormwater management.

Hobsons Bay City Council (HBCC) has embarked upon a process to review and revise its Stormwater Management Plan (SWMP), which was prepared in 1999. The review is being undertaken in order to:

• Ensure Council’s approach to stormwater management addresses the priorities of the Hobson’s Bay community;

• Identify gaps in Council’s stormwater management, particularly in relation to new and emerging management techniques.

The revised and updated SWMP will guide HBCC in improving environmental management of stormwater. The development of the Plan is being undertaken in accordance with the revised Chapter 3 of the Best Practice Environmental Management Guidelines (BPEMG) Urban Stormwater (1999). The process involves the identification of Priority Management Issues and the recommendation of strategies that respond specifically to these issues. The process adopted in developing the plan and identifying Priority Management Issues is outlined in Figure 1-1.

Figure 1-1 Stormwater Management Planning Process

The identification of the Priority Management Issues involved a desktop review of available information and consultation with community and council representatives through a stakeholders meeting.

This paper outlines the Priority Management Issues that have been identified, which form the basis for developing management strategies. The identification of these issues has considered:

• Beneficial uses of the receiving environment within and adjacent to urban catchments within the council boundary (Values);

Identify LocalStormwater

ManagementIssues & Strengths

Management Framework Review

Preliminary Activities

ValuesAssessment

Collate andReview Available

Data

StormwaterThreats

RiskAssessment


Strategies


REA

CTI

VE

PR

OA

CTI

VE

RISK Management Management PlanDevelopment

Phase 2Phase 1 Phase 3

PriorityManagement

Issues

SubmitStormwater

ManagementPlan

FinaliseStormwater

Management Plan

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INTRODUCTION 1-2


• Significant stormwater pollutant sources within catchments throughout residential, commercial and industrial zones of the council (Threats); and

• Consequences of impacts to the receiving environment (Risks).

Priority Management Issues are defined by identified risks and opportunities to improve how stormwater is managed. These issues will need to be addressed by the Stormwater Management Plan to achieve Best Practice Environmental Management of Stormwater. It is important that agreement and commitment to the Priority Management Issues is achieved before the study proceeds.

SETTING THE SCENE 2-1


2 SETTING THE SCENE

Hobsons Bay City Council (HBCC) consists of approximately 6,440 hectares of residential, commercial and industrial land west of Melbourne (Figure 2-1) on the coastline of Port Phillip Bay. The region encompassed by HBCC includes the localities of Williamstown, Newport, Laverton and Altona. The Hobsons Bay City Council contains a vast variety of land uses ranging from petroleum refining on the banks of the Kororoit Creek, walking and cycling trails along the coastline, RAMSAR listed wetlands and the ever increasing pressure on land for inner-city living.

The location of Hobsons Bay on the edge of Port Phillip Bay has meant that it contains the river mouths of all major waterways within its jurisdiction. These waterways, including Kororoit, Skeleton, Cherry, Laverton and Stony Creeks, extend beyond the boundary and thus the control of HBCC. Therefore, the impacts of land use and land management practices upon these waterways outside HBCC can still be seen on the waterways and coastline of Hobsons Bay. Consequently, the Hobson Bay Stormwater Management Plan must involve communication and coordination of activities with neighbouring councils and regional bodies, such as Melbourne Water and the Environment Protection Agency (EPA Victoria).

In addition to these waterways, a number of wetlands of significance exist within the council boundary. The wetlands include Stony Creek Backwash, the Jawbone Reserve, Cherry Lake, lower Kororoit Creek, Truganina Wetlands and Cheetham Wetlands. These wetlands are of significance because they provide habitat for local species and for wading birds that migrate annually from Siberia and Japan (Hobsons Bay City Council, 1997). A number of these species are protected under the Japan Australia Migratory Birds Agreement and the China Australia Migratory Birds Agreement. These treaties require the protection of nominated species such as the Lathams Snipe and Curlew Sandpiper and of the habitats on which they depend. Associated with these wetlands is open space providing valuable recreational opportunities for residents and visitors.

The City of Hobsons Bay supports viable populations of the small Golden Moths Orchid and the Altona Skipper Butterfly. The butterfly lives in the Chaffy Saw Sedge, which grows on the margins of Truganina Swamp, Cherry Lake and Cheetham Wetlands.

The natural and ecological values are just one aspect of the overall value of the Hobson Bay waterways. Cherry Lake is a significant recreational reserve for residents of Altona. The waterbirds, the lake and the peacefulness the park offers, are common reasons why people visit Cherry Lake (Thompson & Berrill, 1997). The foreshore area, in particular the Williamstown foreshore area, The Strand, The Esplanade and sandy beaches, are valuable recreational resources for both residents and tourists. The maritime theme of this area, the existence of numerous heritage features, the streetscape and gardens, attract many tourists. The area also has a high economic value hosting numerous restaurants, cafes, galleries and gift shops. The sandy beaches of Altona and Williamstown are very popular and are considered two of the most popular recreation destinations in the western region of Melbourne (Hobsons Bay City Council, 1997). Nature reserves such as the Cheetham Wetlands and the Jawbone Reserve are less well-known attractions but will increase with importance with further urban development and connection of bayside trails along the foreshore (Hobsons Bay City Council, 1997).



The values and functions of creeks, wetlands and the Bay are under threat from numerous activities, which affect the quality and quantity of urban stormwater. The land in the City of Hobsons Bay is largely developed. The City has a population of 72,000 and is expected to grow to 80,414 by the year 2011 (Hobsons Bay City Council, 1997). The City supports numerous activities that contribute pollutants to urban runoff and hence to receiving waters of the stormwater system. These include, but are not limited to residential activities and large industrial areas. Housing densities within the City of Hobsons Bay are low, with over 83 percent of the city’s dwellings being detached. Industrial complexes are located close to residential areas. Hobsons Bay is home to the State’s petrochemical industry and one of the States two petroleum refineries. Shipbuilding, motor vehicle manufacturing, power generation, railway maintenance, transport and storage are other major enterprises.

Stormwater impacts are related to the major land uses and key activities undertaken within the municipality. Figure 2-3 and Table 2-1 highlight the key land use zones present in Hobson Bay City Council. These various land uses (residential, industrial, commercial, etc) each pose a different threat to the surrounding environment values and consequently impact upon the risk to each value.

The issue of litter within the stormwater system applies to the entire municipality. A particular form of litter, syringes, poses a high risk to the recreational and tourism value of the beaches and indirectly the economic value of the area adjoining the beach. Likewise, litter emanating from the Williamstown town centre can cause degradation of habitat values and the recreational experiences of visitors, as well as decreasing the hydraulic capacity of the stormwater system.

Hobsons Bay supports a large industrial area. The main risk associated with industry is potentially contaminated runoff and the risk of spills entering the stormwater system. The pollutants that would enter Kororoit Creek, Cherry Lake or Truganina Swamp in the event of a spill or contaminated runoff are toxic and pose a serious risk to the habitat and instream values associated with these environments. Wading Birds, which are valued by the local and international community, would be severely affected by a toxic spill.

The values of Hobsons Bay’s stormwater system are strongly influenced by activities in neighbouring Councils. Major housing developments to the north and south of the Princess Freeway within the City of Wyndham could add about 180,000 people to the population with the potential for major impacts on the hydrology, water quality and ecology of Skeleton Creek and Cheetham Wetlands. Melbourne Water does impose requirements relating to the drainage schemes on new developments to ensure flood levels remain at pre-development levels both at the development and in the floodplain around the development.

OCEANICS AUSTRALIA

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Hobsons Bay City Council Locality Map Figure 2.1

2-3SETTING THE SCENE

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Hobsons Bay City Council Boundary, Major Waterways and Drains Figure 2.2


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Major Waterway / Drain

Hobsons Bay Boundary

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Hobsons Bay City Council Planning Codes Figure 2.3


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Hobsons Bay Planning Codes

Commonwealth LandComprehensive DevelopmentIndustrialPort of Melbourne Planning SchemePublic Conservation and ResourcePublic LandPublic Park and RecreationResidentialRoadSpecial UseUrban Floodway

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2.1 Hobsons Bay Catchments

Hobsons Bay City Council broadly consists of five waterway catchments and a number of coastal catchments. These catchments have been defined as the region or regions contributing to a single outlet (either the creek mouth or a drainage pipe). Each of these catchments contains within their boundaries a variety of land uses (Table 2-1) and each is important when determining the values of and threats to the waterways and receiving waters. These overriding catchments are shown in Figure 2-4.

Table 2-1 Major Land Uses in Hobsons Bay

Catchment Major Land Use

Skeleton Creek Residential

Laverton Creek Industrial, Residential

Port Phillip Bay Industrial, Residential

Cherry Creek Industrial, Residential

Kororoit Creek Industrial, Residential

The Range Residential

Williamstown Beach Residential, Commercial, Industrial

Newport Beach Residential, Commercial, Industrial

Stony Creek Residential, Industrial

The overriding catchments have been further divided into subcatchments to aid in the identification of land uses, their associated values and threats. By narrowing the land use, it is easier to address potential stormwater related threats and values. These smaller subcatchments and drainage routes are shown in Figure 2-5.

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Hobsons Bay Stormwater Catchments Figure 2.4


Cherry CreekCherry CreekCherry CreekCherry CreekCherry CreekCherry CreekCherry CreekCherry CreekCherry Creek

Laverton CreekLaverton CreekLaverton CreekLaverton CreekLaverton CreekLaverton CreekLaverton CreekLaverton CreekLaverton Creek

Altona BeachAltona BeachAltona BeachAltona BeachAltona BeachAltona BeachAltona BeachAltona BeachAltona Beach

AltonaAltonaAltonaAltonaAltonaAltonaAltonaAltonaAltona

Skeleton CreekSkeleton CreekSkeleton CreekSkeleton CreekSkeleton CreekSkeleton CreekSkeleton CreekSkeleton CreekSkeleton Creek

Kororoit CreekKororoit CreekKororoit CreekKororoit CreekKororoit CreekKororoit CreekKororoit CreekKororoit CreekKororoit Creek

Stony CreekStony CreekStony CreekStony CreekStony CreekStony CreekStony CreekStony CreekStony Creek

Williamstown/NewportWilliamstown/NewportWilliamstown/NewportWilliamstown/NewportWilliamstown/NewportWilliamstown/NewportWilliamstown/NewportWilliamstown/NewportWilliamstown/Newport

The RangeThe RangeThe RangeThe RangeThe RangeThe RangeThe RangeThe RangeThe RangeWilliamstown BeachWilliamstown BeachWilliamstown BeachWilliamstown BeachWilliamstown BeachWilliamstown BeachWilliamstown BeachWilliamstown BeachWilliamstown Beach

These Catchments have been derived initially upon existing catchment boundaries data and secondly by pipe alignment data

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Catchment Boundary

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Hobsons Bay Stormwater Sub Catchments and Drainage Routes Figure 2.5


These Catchments have been derived initially upon existing catchment boundaries data and secondly by pipe alignment data

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Sub Catchment Boundary

Drainage Direction



2.2 Existing Stormwater Management Plan

Hobsons Bay City Council developed a stormwater management plan in 1999 with the help of AWT Victoria and TBA Planners. As part of the development of a new stormwater management plan, a review of the existing plan has been undertaken.

The existing plan identified (through a series of stakeholder workshops) a number of stormwater issues, values and activities that posed a threat to stormwater quality. With this information and subsequent risk analysis that was undertaken, a series of eight strategies were formulated. In brief, these strategies were to:

1. Improve the planning framework to enable integrated stormwater management

2. Improve coordination of stormwater management between councils and relevant authorities

3. Improve site management of construction activities

4. Promote water sensitive design principles

5. Reduce litter entering receiving waterways

6. Increase awareness of stormwater management and facilitate community participation in stormwater management

7. Improve site management of industrial activities

8. Refine and update a monitoring program

These strategies were to be implemented by the relevant authorities and in the allocated timeframe according to the implementation plan (section 6) of the existing stormwater management plan.

A detailed comparison of the values, threats, and risks utilised in the 1999 Plan and the current Plan has been undertaken and is presented in Appendix C.

An assessment of the implementation of the actions within the 1999 Plan has been undertaken by the HBCC and is contained within Appendix D. A number of the actions have been implemented and other related projects undertaken to improve stormwater since the Plan was completed. In addition a number of projects were undertaken with funding assistance from VSAP, and these are also described in Appendix D.

STORMWATER MANAGEMENT ISSUES 3-1


3 STORMWATER MANAGEMENT ISSUES

3.1 Stormwater Risk Assessment

Priority management issues were identified through a risk assessment process. The aim of the stormwater risk assessment is to identify areas where the risk of losing or degrading environmental values is greatest. Risk assessment is concerned with balancing the probability of impact against the consequence of the impact. This is applied in the Urban Stormwater Management Planning process by assessing the significance of receiving values, magnitudes of stormwater threats, and how they relate to one another.

The risk assessment was conducted by evaluating the various threats and risks within each catchment. As shown in Table 3-1, each value or threat is scored as being low, moderate, high or very high. The risk is then determined by multiplying the value by the threat by a sensitivity factor (Figure 3-1).

Threatfrom stormwater pollution orflows:- scale or severity- likelihood or frequency

Valueof receiving environment:- sensitivity; and- significance

Threat x Value x Sensitivity

RISKof losing environmental/amenity value

Figure 3-1 Risk Assessment

The qualitative scores for threats and values identified in the following sections were substituted with quantitative scores from 1 to 4 to undertake the risk magnitude calculation (Figure 3-1).

A score of 1 to 4 was also ascribed for the perceived sensitivity of a value to a given threat. The sensitivity score considers:

• spatial locality of specific threats in relation to values; and

• how a value is likely to be impacted by a specific threat.

Results of the risk assessment (including risk, values and sensitivity scores) for each Catchment are provided in Appendix B.

In some instances specific threats are not related to values within the same node. For example, the threat may actually occur downstream of the specific value that contributes to its high rating in a particular node. Alternatively, a particular value may not be sensitive to the specific pollutants generated by a threat. The sensitivity score provides a basis for reflecting these interactions.



Table 3-1 summarises the range of qualitative ratings and their corresponding quantitative scores. For ratings that fall between whole values (e.g. high to very high), a half score is ascribed (e.g. 3.5).

Table 3-1 Score System for Threats, Values and Sensitivity

Score Threats Value Sensitivity 1 Low Low Low 2 Moderate Moderate Moderate 3 High High High 4 Very High Very High Very High

3.2 What are the Key Values?

Hobsons Bay City Council is located upon the coast of Port Phillip Bay, contains numerous waterways, possesses wetlands of state, national and international significance and has coastal regions with high economic and amenity values. Values have been identified in the receiving waterways and riparian environments of each catchment to assist in identifying priorities to address the activities that either currently or potentially threaten these values. Values will be identified as being of low, medium, high or very high value and include: • Environment (Aquatic Habitat, Riparian Habitat and Faunal Habitat); • Amenity (Recreation and Visual Landscape Amenity); • Economic (Tourism) • Hydraulic (Flood Conveyance); and • Receiving Environment (Receiving Waters).

Each value type is summarised in Table 3-2 and discussed in more detail in the following sections.

Table 3-2 Value Types

Value Category Specific Value Types Description Environment Aquatic Habitat In-stream ecological values based on water quality, habitat

quality and diversity, flora and fauna species, extent of invasion by exotic species and general in-stream condition and stability.

Riparian Habitat Waterway condition and ecological values based on extent and quality of remnant (native) vegetation, weed infestation and stability of riparian zone.

Faunal Habitat Altona Skipper Butterfly and rare and endangered water bird habitat values based on the extent and quality of its habitat that will ensure the conservation of the remaining population.

Cultural Heritage Cultural Heritage Cultural Heritage refers to sites of Aboriginal or European heritage. Site such as Aboriginal Sacred Sites or sites of Historical Importance are examples of values included as being of cultural heritage.

Amenity Recreational Amenity Public access and utilisation for active recreation involving primary contact with water. Swimming in local waterways and the bay are included as recreational amenity.

Visual/Landscape Amenity Aesthetic appreciation of the natural and built environment including consideration of natural and man made structures, landscapes and places of importance, visual access and relationships to adjacent facilities. Active and passive



recreation not involving primary contact with water is also included in this value. Activities such as boating, walking, cycling are considered in this value.

Hydraulic Flood Conveyance Contribution to protection against flooding including consideration of waterway capacity, designated floodwalls and flood protection infrastructure (e.g. levees).

Economic Tourism The primary economic source that can be impacted by poor stormwater management resulting in loss of recreational/visual/landscape amenity and creation of public health and safety hazards.

Receiving Environment

Receiving Waters Significance of the regional environment into which stormwater ultimately discharges includes the Yarra River and Port Phillip Bay.

3.2.1 Aquatic Habitat

Hobsons Bay is in the unique position to have numerous waterways, lakes and wetlands in an urban setting. Each of these waterways can potentially provide habitat for a variety of flora and fauna; however, the quality of this habitat will determine the extent to which indigenous communities are supported. By supporting a variety of wildlife and plants, these waterways will further improve their health and ability to maintain high water quality.

3.2.2 Riparian Habitat

Hobsons Bay City Council has constructed numerous cycling and walking trails along a number of the waterways in the region. Part of the appeal of these trails is the ability to connect with nature and see local wildlife. Established trees and shrubs help to support breeding populations of native birds and improve the attractiveness of the region. This can help to encourage residents and visitors to use the facilities provided by council more often and help to allow the local community take more pride in their waterways.

3.2.3 Faunal Habitat

Hobsons Bay contains some very significant habitat for some rare and endangered birds and insects. Significant water bird sites exist at Cheetham Wetlands and the Altona Coastal Park. Many of these water birds are migratory and are protected under several international agreements.

Hobsons Bay provides habitat to support populations of Golden Moths Orchid and Altona Skipper Butterfly. Cherry Lake, Truganina Swamp and Cheetham wetlands are the only sites within Hobsons Bay where suitable habitat is provided for the butterfly.

3.2.4 Cultural Heritage

Hobsons Bay, and in particular Williamstown, has significant cultural heritage. Williamstown has Point Gellibrand that has heritage values (an old sea port and convict destination, the fort), maritime significance (time ball tower, the Alfred Graving Dock) and the historic precinct of Nelson Place. Hobsons Bay also has aboriginal heritage at several sites such as the Altona Coastal Park, and Skeleton Creek.



3.2.5 Recreation Amenity (swimming)

Hobsons Bay City Council posses two of only three monitored swimming beaches west of Melbourne. Consequently, these two beaches (Williamstown and Altona) are extremely popular during summer, attracting visitors from the neighbouring councils and regions. The attraction of swimming in the western suburbs also has added value for the Hobsons Bay City Council through the commercial premises and activities that rely on the tourist trade.

3.2.6 Visual/Landscape Amenity (including boating)

The entire southeast boundary of Hobsons Bay is along the coast of Port Phillip Bay. The views and opportunities these provide for both residents and visitors are extremely important for the municipality. Bike and walking trails along the foreshore, numerous boating and yacht clubs, fishing clubs and picnic facilities are all available within the boundary of the council. Without good water quality and visually attractive waterways and receiving waters, many of these activities would dramatically decline in patronage, impacting upon the local community.

3.2.7 Flood Conveyance

Being situated on the coast of Port Phillip Bay and having a very flat gradient, the City of Hobsons Bay has a number of areas where flood and drainage waters collects. Combined with an old and generally undersized drainage network, flooding problems can be a frequent problem. In an effort to combat these problems, Melbourne Water has undertaken a number of drainage improvement works to protect properties from flooding, including the construction of retarding basins (Cherry Lake and Truganina Swamp) and flood levees (along lower Kororoit Creek and around Truganina Swamp). A decrease in flood conveyance will result in increased flooding risk and consequently will result in more frequent and severe flooding.

3.2.8 Tourism

Hobsons Bay has high tourist values. Monthly markets at Commonwealth Reserve, shopping along Nelson Place, relaxing at Greenwich Bay, Cherry Lake and swimming at the Williamstown and Altona beaches all attract large number of tourists to the region. All these attractions are within 50 metres of either Port Phillip Bay or a local waterway and as such can be severely impacted by water quality and its visual appearance.

3.2.9 Receiving Waters

The main receiving waters of the Hobsons Bay City Council are Port Phillip Bay. Stony Creek does drain into the Yarra River that in turn drains to Port Phillip Bay. The Bay is important to the community of Hobsons Bay, many local residents using it for fishing and boating. Port Phillip Bay also has regional significance and all other coastal municipalities are impacted by the quality of the Bay.

3.3 Values Assessment

The traditional risk assessment process used to identify priority stormwater issues was developed for municipalities where a variety of environmental values ranging from low to very high exist. The



segment called ‘Port Phillip Bay’ on the coast of Altona has no natural waterways and was therefore assessed as having no value for aquatic and riparian habitat. All other values assessments for stormwater catchments within Hobson Bay are shown below in Error! Reference source not found.. Ranking environmental values enabled prioritisation of stormwater issues across the municipality based on the magnitude of the threat and the value of the receiving environment that the threat impacts upon.

Table 3-3 Summary of Values Assessment

Skel

eton

Cre

ek

Lave

rton

Cre

ek

Alto

na

Che

rry

Cree

k

Kor

oroi

t Cre

ek

The

Rang

e

Will

iam

stow

n B

each

Alto

na B

each

Will

iam

stow

n / N

ewpo

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Ston

y C

reek

Aquatic Habitat Mod Mod High High High High High Low Mod

Riparian Habitat Mod Mod High High High Low Low Low Mod Environmental

Faunal Habitat Very High

Very High Mod High Very

High Very High Mod Mod Mod Mod

Cultural Heritage Cultural Heritage Mod Mod Low Low High High Mod Mod Very High Mod

Recreational Amenity (Swimming) Low Low High Mod Low Low Very

High Very High High Low

Amenity Visual / Landscape Amenity (including boating)

Very High High Very

High Very High High Very

High Very High

Very High

Very High High

Hydraulic Flood Conveyance Low Very High High Very

High Low High Very High

Very High

Very High

Very High

Economic Tourism Very High High Very


High Very High

Very High

Very High High

Receiving Waters Port Phillip Bay Very High

Very High High Very



High

3.4 What are the Key Stormwater Threats?

Stormwater threats generally relate to potential pollutant sources or changes in flow regime that may impact on receiving environments. Threats can arise from a range of sources including specific land use types, activities (eg. manufacturing), infrastructure (eg. residential and commercial sites) and ongoing development. The identification of stormwater threats throughout the Hobsons Bay City Council was based on:

• Review of available land use data including planning scheme codes and aerial photography;

• Field investigations to determine and understand the nature of specific land use types and activities, including variability within land use types; and

• Discussions and workshops with council and community stakeholders.



The identification and characterisation of stormwater threats considered in detail the specific activities that are taking place within a particular land use that may be generating the threat. For example, all residential and commercial areas will not generate the same type or magnitude of stormwater threat.

For each activity and land use type the following was considered:

• the types of pollutants that may be generated;

• the way in which the pollutants are generated (eg. atmospheric deposition or poor waste management);

• existing management measures and systems that guard against their generation; and

• how they are conveyed or transported to the receiving stormwater system (and ultimately the environment).

Threats associated with stormwater pollutants and flow regimes were characterised using a series of qualitative indicators, which consider:

• the spatial extent of the threat (local or regional);

• the magnitude of the threat (severity); and

• the frequency of the threat.

Each of these indicators was evaluated for each threat in each sub-area to provide qualitative measures for all threats across all sub-areas in the municipality.

3.4.1 Definition of Threats

Table 3-4 summarises the range of generic stormwater threats that have been defined across the Resort, including details of the sources and types of pollutants associated with each threat and how they are generated. Table 3-5 outlines the key pollutant impacts and associated time scales.

Table 3-4 Generic threats adopted for the Hobson Bay City Council Threat Cause Key Pollutants and Impacts Waterway degradation

Poorly controlled stock and recreational access, weed infestation, damage from waterway works, development encroachment, vegetation loss, and eroded and unstable riparian zones

Sediment, nutrients, oxygen depleting material

Residential Runoff Atmospheric deposition and build-up from traffic, washing cars, fertiliser application, poor waste management (domestic refuse), dumping of residential rubbish, lawn clippings and vegetation

Increased flow, sediment, nutrients, litter, oxygen depleting material, hydrocarbons, pathogens, trace metals, pesticides

Industrial Runoff Atmospheric deposition and build-up from traffic, poor waste management, accidental spills and illegal discharges

Increased flow, sediment, nutrients, litter, oxygen depleting materials, hydrocarbons, pathogens, trace metals, pesticides, surfactants

Commercial Runoff Atmospheric deposition and build-up from

traffic, poor waste management practices

Increased flow, sediment, nutrients, litter, oxygen depleting material, hydrocarbons, pathogens, trace metals, surfactants

Major Road / Rail Runoff

Atmospheric and vehicular deposition and accumulation and the effects of road/rail

Sediment, litter, trace metals and hydrocarbons



construction Building Site Runoff

Poor management of building site waste and materials Sediments, nutrients

Open Space Runoff Wash off of nutrients (fertilisers) and litter from public gardens, parks, sporting facilities, golf courses and discharge of poor quality water from ornamental lakes

Nutrients, litter, oxygen depleting materials

Residential / Industrial Development

Poor sediment and erosion control, uncontrolled wash down of equipment, deposition of sediment, vehicles and spills from construction process (eg concreting)

Sediments, nutrients

Unsewered Properties

Infiltration and overflow from sewerage systems and septic tanks

Oxygen depleting material, pathogens, nutrients

Upstream Inflows Runoff from upstream catchments, entering via creeks and waterways Sediment, nutrients, litter, pathogens

Contaminated Land/Groundwater

Inappropriate disposal of waste materials, leaching of contaminants

Oxygen depleting substance, pathogens, hydrocarbons and toxic substances

Boat Ramps Runoff from boat ramp areas including atmospheric deposition, rubbish, oils and fuels from boats and vehicles and accidental spills

Sediment, oxygen depleting materials, litter, oils and greases, trace metals, toxic substances



Table 3-5 Pollutant Impacts and Time Scales

Parameter Potential Impacts Time Scale

Hydraulic Effects – Increased flow

Increased flow rates and velocities increase the frequency of bed disturbance Changes to substrate characteristics as a result of the removal of easily eroded materials Increased rates of bed erosion and nick point retreat Higher sediment transport rates Reduced opportunity for watercourse geomorphology to recover

Instantaneous to hours

Hydraulic Effects – Reduced flow

Reduced flushing and water turn over, increasing stagnation Weeks to months

Suspended Solids Reduced light penetration, affecting photosynthesis rates of algae Clogging of gills of fish and invertebrates Blanketing of moss beds Reduced substrate habitat value, including filling of voids in gravel substrates This affects invertebrates and some fish, who require voids for feeding and respiration Increased sediment deposition can reduce food supplies for some invertebrates Reduction in quality and quantity of water supply Sedimentation can bury indigenous vegetation, restrict growth

Days to years

Nutrients Increased algae concentrations, often favouring blue-green algae (cyano bacteria) Increased growth of aquatic plants, but often reduced diversity Reduced diversity of invertebrates and fish Increased turbidity due to algal growth Lowering of dissolved oxygen levels due to algal decay

Months to years

Litter Physical harm to aquatic biota Visual impact reduces recreation and landscape amenity, tourism value Reduction in habitat value

Weeks to years

Oxygen Demanding Materials

Reduced dissolved oxygen concentrations Reduced diversity of fish and invertebrates Change in the structure of macro invertebrate communities (e.g. domination by worms) Hindered respiration of fish, possibly reaching lethal levels Increased levels of bacteria and some algae (particularly filamentous green algae) Decreased growth of most aquatic plants Very low oxygen levels may increase the release rate of nutrients and metals from sediments

Hours to weeks

Pathogens Bacteria and other pathogens may affect human health Impact quality of water supply

Less than 1 week

Toxic Organics (eg. Pesticides)

May be lethal to fish and invertebrates at high levels (rare in stormwater) and can bioaccumulate in the food chain, affecting predators Low levels may hinder reproduction by fish and invertebrates Herbicides may reduce the abundance of algae and aquatic plants Reduce quality of water supply

Years

Toxic Trace Metals Toxic to fish, invertebrates, algae and aquatic plants and can bio-accumulate in the food chain, particularly affecting predators Generalised toxicity ranking of metals commonly found in stormwater is (high to low) as follows: Copper, cadmium, zinc, lead, aluminium, nickel, iron, chromium Reduce quality of water supply

Years

Oils and surfactants High levels of hydrocarbons and surfactants are toxic to fish, invertebrates and aquatic plants Reduction in quality of water supply Reduction in photosynthesis, affecting algae, mosses and aquatic plants Fish respiration and feeding may be hindered by hydrocarbons

Hours to months

Weeds Reduce indigenous flora and fauna habitat availability and diversity Visual impact reduces recreation and landscape amenity, tourism value

Months to years



3.4.2 Assessment of Threats

The scoring of the key stormwater threats within the Hobsons Bay City Council are presented in Table 3-6 and a brief explanation behind each high and very high threat rating for the various catchments is detailed in the following sections. Scoring of all the stormwater threats in each catchment is presented in Appendix A.

Table 3-6 Summary of Threats Assessment

Skel

eton

Cre

ek

Lave

rton

Cre

ek

Alto

na

Che

rry

Cree

k

Kor

oroi

t Cre

ek

The

Rang

e

Will

iam

stow

n B

each

Alto

na B

each

Will

iam

stow

n / N

ewpo

rt

Ston

y C

reek

Waterway Degradation High Mod High Very High High

Residential Runoff Very High High Very

High High Very High

Very High

Very High

Very High

Very High

Very High

Industrial Runoff Low Very High Low Very

High Very High Low Low Low High Very

High

Commerical Runoff High High Mod Low High Mod Very High

Very High

Very High High

Major Road / Rail Runoff Very High

Very High Mod Very

High Very High Mod Mod Mod High Very

High

Building Site Runoff Mod Mod High Mod High Low High High High High

Open Space Runoff Mod Mod Mod Mod Mod Mod Mod Mod Mod Mod

Residential / Industrial Development Mod High High Very High High Low Low Low Low Low

Unsewered Properties Low Low Low Low High Mod Mod Mod Mod

Upstream Inflows High Mod Very High

Very High Very

High

Boat Ramps Very High High Mod Very

High

Contaminated Land / Groundwater Low High Low Very High

Very High Low Low Low Mod High

Waterway Degradation

Kororoit Creek catchment has been well developed with industrial and warehousing operations resulting in a significant decrease in the pervious area. This has resulted in increased runoff into Kororoit Creek and when combined with pressures upon the creek system (recreational access, waterway works) has the potential to cause waterway degradation through increased erosion and



sediment movement. Consequently, this catchment has been assessed as having a very high threat to urban stormwater quality.

Skeleton Creek, Cherry Creek and Stony Creek catchments have had extensive development (mostly residential housing), built in close proximity to the creek system. The urban nature of the catchments when combined with this style of development has the potential to pose a threat to the natural waterways. Therefore, these catchments have been assessed as having a high threat to urban stormwater quality.

Residential Runoff

Skeleton Creek, Port Phillip Bay, Kororoit Creek, The Range, Williamstown/Altona Beaches, Williamstown/Newport and Stony Creek catchments all contain high percentages of residential properties within their respective boundaries. Activities such as car washing and inappropriate disposal of garden waste and domestic refuse can all decrease the quality of urban stormwater runoff. In addition the road network can be a source of pollutants produced by motor vehicles and spills. The threat of runoff from residential properties within these catchments has been assessed as being a very high urban stormwater threat.

Laverton Creek and Cherry Creek catchments also contain residential areas, however they constitute a smaller percentage of the catchment than the other previously mentioned catchments. The issues associated with residential runoff remain, however. The threat of runoff from residential properties within these catchments has been assessed as being a high urban stormwater threat.

Industrial Runoff

The Laverton Creek, Cherry Creek, Kororoit Creek and Stony Creek catchments contain extensive industrial sites within their respective boundaries. The Kororoit Creek catchment in particular is home to the Altona petrochemical complex and one of Victoria’s two petroleum refineries. The threat of runoff from these sites and all other industrial premises within these catchments has been assessed as being a very high urban stormwater threat.

Williamstown/Newport catchment whilst being predominantly residential, does contain some industrial premises in the northeast region and the shipyards in the south. The threat of runoff from these sites and all other industrial premises within this catchment has been assessed as being high.

Commercial Runoff

Williamstown/Altona Beaches and Williamstown/Newport catchment include some of the main commercial districts within Hobson Bay City Council. The shopping strip along Ferguson St and the commercial precinct along Nelson Place are two of the key commercial threats to urban stormwater quality. The threat of runoff from these sites and all other commercial premises within these catchments has been assessed as being a very high urban stormwater threat.

Skeleton Creek, Laverton Creek, Kororoit Creek and Stony Creek catchments contain some of the more moderate commercial regions. Altona Gate and Central Square Shopping Centres and ‘The Circle’ shops are some of the numerous commercial premises that pose a threat to urban stormwater quality. Commercial premises within these catchments have been assessed as having a high threat to urban stormwater quality.



Major Road/Rail Runoff

The Skeleton Creek, Laverton Creek, Cherry Creek, Kororoit Creek and Stony Creek catchments all contain within their respective boundaries numerous major roads, including the Westgate Freeway (Princes Freeway). Many of the secondary roads within these catchments are also utilised by trucking companies for access to the many industrial and warehousing premises in the region. The threat of runoff from these sites and all other industrial premises within these catchments has been assessed as being a very high urban stormwater threat.

The Williamstown/Newport catchment contains a number of secondary roads that have the potential to pose a threat to urban stormwater. Combined with these secondary roads, this catchment also includes locomotive maintenance, storage and restoration facilities. The threat of runoff from these sites and all other industrial premises within these catchments has been assessed as being a high urban stormwater threat.

Building Site Runoff

Port Phillip Bay (Altona), Kororoit Creek, Williamstown/Altona Beaches, Williamstown/Newport and Stony Creek catchments are considered to contain reasonable opportunities for small-scale building activities. Consequently, the threat of runoff from building sites within these catchments has been assessed as being a high urban stormwater threat.

Open Space Runoff

Open Space Runoff in all catchments has been assessed as being a moderate threat. Whilst open spaces can contribute sediment, nutrients and litter to the local environment, it has been determined that the increased pervious area will reduce this overall threat.

Laverton Creek, Cherry Creek, Kororoit Creek and Williamstown/Newport catchments all contain within their respective boundaries considerable areas of open space. Altona Lakes Public Golf Course, the Kooringal Golf Club, J.K. Grant Reserve, coastal reserves, Truganina Park and the Williamstown Cricket Ground are all sites of open space that have the potential to impact upon urban stormwater quality. The threat of runoff from these sites and all other open spaces within these catchments has been assessed as being a moderate urban stormwater threat.

Residential/Industrial Development

Cherry Creek catchment has the potential for large-scale industrial, commercial or residential developments. The available land in this catchment has resulted in it being assessed as having a very high threat to urban stormwater quality.

Laverton Creek, Port Phillip Bay (Altona) and Kororoit Creek catchment has the potential for medium-scale industrial, commercial or residential developments. The available land in this catchment has resulted in it being assessed as having a high threat to urban stormwater quality.


Kororoit Creek catchment contains approximately 110 sites (60 industrial) that are not connected to the sewerage system and hence rely on septic tanks for effluent disposal. These sites include ‘The



Pines’ Scout camp and the Kororoit Creek Fishing Village. The threat of untreated sewerage entering the Kororoit Creek has been assessed as being high to urban stormwater quality.

Upstream Inflows

Cherry Creek, Kororoit Creek and Stony Creek catchments have a large percentage of their overall catchments under the jurisdiction of surrounding councils (Maribyrnong, Brimbank, Melton and Wyndham) and consequently the water entering Hobsons Bay from these neighbouring councils potentially poses a threat to the water quality of Hobsons Bay. The nature of activities and size of the upstream catchments has resulted in these catchments being assessed as having a very high threat to urban stormwater quality.

The Skeleton Creek catchment has a moderate percentage of its overall catchment under the jurisdiction of the surrounding councils (Melton and Wyndham) and consequently the water entering Hobsons Bay from these neighbouring councils potentially poses a threat to the water quality of Hobsons Bay. The nature of activities and size of the upstream catchments has resulted in these catchments being assessed as having a high threat to urban stormwater quality.

Boat Ramps

Cherry Creek and Williamstown/Newport are two catchments where boating and fishing are major recreational activities. The Williamstown/Newport catchment is home to Royal Yacht Club of Victoria, various other yacht and boating clubs, and recreational boat ramps at ‘the Warmies’. Adjacent to the outlet of Cherry Creek is a major regional boating facility, the Altona Boat Ramp. The threats associated with boat ramps include discharge of hydrocarbons into the waterways, litter and sediment re-suspension, all of which can reduce water quality. Due the number of boat ramps within these two catchments, the catchments have been assessed as being a very high threat to urban stormwater quality.

Kororoit Creek catchment whilst having no boat ramps, does contain the local fishing village. The activities of this fishing village pose a similar threat to a boat ramp (through the activities of the fisherman). Therefore, this catchment has been assessed as having a high threat to urban stormwater quality.


Cherry Creek and Kororoit Creek catchments have had a long history of industrial usage. Past industrial activities and practices have the potential to create major threats to urban stormwater quality. Contaminated groundwater plumes moving through the groundwater system are an example of this, especially where interchange between the groundwater and surface water occurs. Due the size and nature of previous industrial sites and known groundwater contamination issues these catchments have been assessed as being a very high threat to urban stormwater quality.

Laverton Creek and Stony Creek catchments have similar histories to Cherry and Kororoit Creek, however as they have occurred on a smaller scale, these catchments have been assessed as being a high threat to urban stormwater quality.



3.5 Risks

Risks are determined by assessing how specific threats may impact on receiving values. As all regional and local values are considered consistently very high, the ultimate risk rating for each stormwater catchment is largely determined by the magnitude of the threat and the sensitivity of local and regional receiving values to that threat. Table 3-7 summarises the priority risks determined for Hobsons Bay City Council.

The risk assessment helps to prioritise and target management strategies. Risk assessment characterises the nature of impacts by considering threats and consequences. With respect to the Stormwater Management Planning process the ‘threat’ relates to activities that pollute stormwater or change its natural characteristics (e.g. increased flow rates). The ‘consequence’ refers to values and the nature of impacts to these values generated by the threat.

Table 3-7 Priority Stormwater Risks in Hobson Bay City Council

Threat Location Key Values Risk

Cherry Creek Laverton Creek Kororoit Creek Williamstown /

Newport Stony Creek

Visual/Landscape Amenity (including boating)

Visual and landscape amenity will be decreased as a result of industrial pollutants in the creek system. Detergents and other chemicals may cause the creek to ‘foam’ and create an odour. Toxic discharges may prevent fishing and boating

Laverton Creek Cherry Creek

Kororoit Creek Stony Creek

Port Phillip Bay (Receiving Waters)

The pollutants generated by industry and present in industrial runoff will decrease the quality and overall health of the receiving waters (Port Phillip Bay)

Industrial Runoff

Laverton Creek Kororoit Creek Faunal Habitat The quality of runoff could adversely affect

the habitat requirements of the local fauna Skeleton Creek Laverton Creek Cherry Creek

Kororoit Creek Williamstown /

Newport Stony Creek


Generation of hydrocarbon and sediments from major road / rail areas will degrade the regional and visual/landscape values. Major

Road/Rail Runoff

Skeleton Creek Laverton Creek Cherry Creek



Generation of hydrocarbon and sediments from major road / rail areas will degrade the quality and appearance of the receiving waters (Port Phillip Bay)

Skeleton Creek Cherry Creek



Visual and landscape amenity will be decreased as a result of the quality and nature of upstream inflows. Pollutants in the river will decrease the visual amenity, whilst increased flow could induce scour and erosion causing a decreased landscape amenity

Upstream Inflows

Skeleton Creek Kororoit Creek Cherry Creek

Faunal Habitat

Increased flows and pollutant loads from upstream inflows will degrade the local environment by inducing scour and causing erosion of native vegetation and the waterway



Cherry Creek Kororoit Creek Aquatic Habitat

The quality and quantity of the upstream inflows will impact upon the aquatic habitat of the creeks and waterways downstream

Cherry Creek Kororoit Creek Riparian Habitat

The quality and quantity of the upstream inflows will impact upon the riparian habitat of the creeks and waterways downstream




Increased flows and pollutant loads from upstream inflows will degrade the quality and appearance of the receiving waters (Port Phillip Bay)

Cherry Creek Tourism The quality and quantity of upstream inflows has the potential to adversely affect the visitor numbers and tourism of the region, impacting upon the local economy

Cherry Creek Williamstown /

Newport


The presence of oils and grease on the water and litter in the surrounding region will decrease the visual and landscape amenity of the site

Cherry Creek Kororoit Creek Williamstown /

Newport


The pollutants generated at the boat ramps (oils, hydrocarbons, litter) will decrease the quality and appearance of the receiving waters (Port Phillip Bay)

Cherry Creek Williamstown /

Newport Tourism

The presence of oils and grease on the water and litter in the surrounding region will decrease the economic value of the region in terms of the tourist dollar

Boat Ramps

Williamstown / Newport Recreational Amenity (swimming)

The presence of oils and grease on the water and litter in the surrounding region will create a hazardous swimming environment

Skeleton Creek Kororoit Creek Faunal Habitat

Degradation of the waterway including increased sediment transport and scour will degrade the faunal habitat by decreasing the health of the waterway and surrounding vegetation.

Kororoit Creek Aquatic Habitat Degradation of the waterway including increased sediment transport and scour will degrade the aquatic habitat by decreasing the health of the waterway



Flood Conveyance

Degradation of the waterway will result in the increased sediment in the system and has the potential to decrease floodplain and river storage, increasing the frequency and severity of floods.


Kororoit Creek Port Phillip Bay (Receiving Waters)

Degradation of the waterway including increased sediment transport and scour will degrade the receiving environment by adversely impacting upon the water’s quality

Skeleton Creek Altona

Cherry Creek Kororoit Creek

The Range Williamstown

Beach Altona Beach

Williamstown / Newport

Stony Creek


Visual and landscape amenity will be decreased as a result of residential pollutants in the creek system. Garden clippings increase the nutrients in the system, whilst car-washing detergent can cause the creek to ‘foam’.

Residential Runoff

Recreational Amenity (swimming)



Altona Williamstown

Beach Altona Beach


The nature and quality of the runoff from residential properties can cause serious health implications for swimmers. These implications depend upon the type and quantity of pollutant present in the runoff

Skeleton Creek Altona

Kororoit Creek Williamstown

Beach Altona Beach Stony Creek


The pollutants generated by residential properties and present in residential runoff will decrease the quality and overall health of the receiving waters (Port Phillip Bay)

Williamstown Beach

Altona Beach Williamstown /

Newport

Tourism The visual nature (garden clippings, etc) of runoff from residential properties will decrease the visual amenity of the region and thus adversely impact upon tourism

Williamstown Beach


Newport

Recreational Amenity (swimming)

The nature and quality of the runoff from commercial properties can cause serious health implications for swimmers. These implications depend upon the type and quantity of pollutant present in the runoff

Skeleton Creek Williamstown

Beach Altona Beach



Visual and landscape amenity will be decreased as a result of commercial pollutants in the creek system. Cooking oils can create oily scums on the water surface whilst litter causes degradation in the visual appearance of the creek.

Williamstown Beach

Altona Beach


The pollutants generated by commercial properties and present in commercial runoff will decrease the quality and overall health of the receiving waters (Port Phillip Bay)

Commercial Runoff

Williamstown Beach


Newport

Tourism The visual nature (litter, etc) of runoff from commercial properties will decrease the visual amenity of the region and thus adversely impact upon tourism

Contaminated Land /

Groundwater Kororoit Creek Faunal Habitat

Contaminants in the local ground or groundwater can enter the surface water system and decrease the quality of the local faunal habitat

3.6 Summary of Key Stormwater Risk Issues

The priority stormwater risks presented in Table 3-7 have been used to identify eight key stormwater management issues that require attention as part of the Stormwater Management Plan. Many of the risks presented above have been grouped with other risks to form a single Priority Management Issue, forming the basis for developing management strategies (particularly where risks in different localities will have similar management responses).

In order to prioritise these risk issues, the frequency of threats contributing to a value was calculated. The threat that is present in the most number of risk issues is thus determined to be the highest priority for the Stormwater Management Plan. The frequency was only calculated for threats contributing to risks where two out of the three elements of risk (value, threat or sensitivity) were determined to be very high.



The key stormwater risk issues that need to be addressed in achieving Best Practice Management of Stormwater are summarised below (frequency of occurrence is shown in brackets).

1. Residential Runoff (22)

2. Upstream Inflows (16)

3. Commercial Runoff (12)

=4. Industrial Runoff (11)

=4. Major Road/Rail Runoff (11)

=6. Boat Ramps (8)

=6. Waterway Degradation (8)

8. Contaminated Land/Groundwater (1)

The threats listed above are those that contribute to the highest risks determined in the risk analysis for Hobsons Bay City Council. This is not to say the other considered in the risk analysis are not important. These risks, although not viewed as priorities, still need to be considered as part of the Stormwater Management Plan. Such consideration will be given during the determination of management strategies, as it is likely strategies targeting the priority issues will provide a benefit to those threats not viewed as priorities. Other threats that will be considered include:

• Building Site Runoff;

• Open Space Runoff; and

• Residential/Industrial Development.

3.7 Water Quality Data

Water quality data is collected regularly at three sites in the City of Hobsons Bay, these being Stony Creek, Kororoit Creek and Skeleton Creek. The data for these three sites were collated and analysed for the last four years from 2000 to 2005 and the results are shown below in Figure 3.2. The most obvious conclusions that can drawn from these results are that almost for all water quality parameters, all three of these waterways exceeded the objectives in the SEPP in some years if not all. Stony Creek is the worst and Skeleton Creek the best of the three. In terms of changes over time it is difficult to make definitive judgments due to the effects of variations in rainfall and other conditions from year to year. Trends in water quality are at best detected over much longer time periods, in the order of ten years to be statistically significant. However, one notable observation is that Stony Creek has improved in a number of parameters since 2000, and this may reflect the results of the water quality improvement program focused on that catchment.

EPA Victoria measures Beach water quality and litter occurrence every year over the summer season. It has not been possible to gain access to all of the data for the last five years to allow an analysis to determine trends or changes over time. However, data for the last two summers have been analysed in order to establish whether there are significant issues associated with the two swimming beaches in the City of Hobsons Bay.



During 2003-4 water quality was good during the summer on the great majority of occasions. However, following heavy rainfall in December and February water quality at Williamstown Beach exceeded objectives and required follow-up sampling. Altona Beach did not meet an SEPP objective for swimming over the summer, only one of three beaches that failed around Port Phillip Bay. It was recommended that pollution sources be investigated at that Beach, with contaminated stormwater as the likely source. Litter was also found on Williamstown Beach, following heavy rain on the 9th March. It was one of the beaches with the most litter, although the report states that it had shown an improvement from previous years, perhaps reflecting the effects of council beach cleaning. The EPA proposed that they would undertake sanitary inspections at Altona Beach as well as others, during the year, looking at sewerage systems, stormwater drains, rivers and creeks to find the sources of pollution.

During the 2004-5 summer a major deluge occurred on 26th January causing a high bacterial level at Williamstown Beach and closing of the beach. By the next day, bacterial levels had returned to their normal, low levels. The following week another, larger storm event caused even more beaches to exceed water quality standards and beach closures. These lasted for several days. While this affected both Williamstown and Altona Beaches, Williamstown Beach had good water quality for the remainder of the summer. Altona Beach however, again showed elevated bacterial levels similar to the previous summer. The storm events also deposited substantial amounts of litter onto the beaches, while Williamstown continued to show high litter levels, partially caused by beach patrons.



Figure 3-2 Water Quality Results 2000-2004

Dissolved Oxygen

0

20

40

60

80

100

120

2000 2001 2002 2003 2004

Year

mg/

l

Stony Creek atBena Street,Yarraville

Kororoit Creek atRacecourse Road,Altona

Skeleton Creek atAyr Street, Laverton

Standard

Turbidity

0

10

20

30

40

50

60

70

2000 2001 2002 2003 2004

Year

NTU

's

Stony Creek at BenaStreet, Yarraville



Standard

TN

0

2

4

6

8

10

2000 2001 2002 2003 2004

Year

mg/

l




Standard

TP

0

0.20.40.60.8

11.21.4

2000 2001 2002 2003 2004

Y e ar

Stony Cr eek at BenaStr eet, Yar r avi l le

Kor or oi t Cr eek atRacecour se Road,Al tona

Skeleton Cr eek at AyrStr eet, Laver ton

Standar d

E.Coli

0

10000

20000

30000

40000

50000

2000 2001 2002 2003 2004

Year

Org

anis

ms/

100m

l




Standard

C opper

0

0.005

0.01

0.015

0.02

0.025

0.03

2000 2001 2002 2003 2004

Y ear


Kor or oi t Cr eek atRacecour se Road,Altona


Standar d

Lead

0

0.005

0.01

0.015

0.02

0.025

0.03

0.035

2000 2001 2002 2003 2004

Year

mg/

l




Standard

Zinc

0

0.1

0.2

0.3

0.4

0.5

2000 2001 2002 2003 2004

Year


Kor or oi t Cr eek atRacecour se Road,Altona


Standar d

BIBLIOGRAPHY 4-1


4 BIBLIOGRAPHY All documents listed below have been reviewed during the generation of this discussions paper, although not all referenced within the document.

AWT Victoria and TBA Planners (1999). Stormwater Management Plan for City of Hobsons Bay

Catchment Development Impact Project. Various Projects undertaken by Hobson Bay City Council as part of the Victorian Stormwater Action Plan (VSAP).

Clearwater Program (2003). Clearwater Website. http://www.clearwater.asn.au/

EPA Victoria (2004). 2003-2004 Beach Summary Report (Electronic Copy, available online)

EPA Victoria (2005). 2004-2005 Beach Summary Report (Electronic Copy, available online)

Hobsons Bay City Council. (1997). Charting our Future: The Hobsons Bay Strategy.

Hobsons Bay City Council. (1997). Hobsons Bay Environment Plan: Charting a Greener Future.

Melbourne Water (2000-2004). Water Quality Data and Healthy Waterways Reports

Thompson Berrill (1997). Cherry Lake Future Directions Plan.

WSUD Guidelines (2004). WSUD Engineering Procedures: Stormwater Technical Manual

SUMMARY OF SCORES FOR CATCHMENT RISK ASSESSMENT


A-1

APPENDIX A: SUMMARY OF SCORES FOR CATCHMENT RISK ASSESSMENT

Skeleton Creek

Background

The Skeleton Creek catchment is located in the southwest corner of Hobsons Bay. Elements of this catchment extend to the south and north into the City of Wyndham and eventually to the City of Melton. The catchment within the City of Hobsons Bay is comprised mainly of residential housing, some of which backs onto the creek. The mouth of Skeleton Creek enters Port Phillip Bay after passing through the Cheetham Wetlands.

Table A-4-1 Skeleton Creek Catchment Summary

Catchment Area 769.6 Hectares Major Land Uses Public Conservation and Resource

Residential Significant Concerns Faunal Habitat

Visual Landscape Amenity (including boating)

Tourism

Port Phillip Bay (Receiving Waters) Number of Pipe Outflows 17 Local Receiving Environment Cheetham Wetlands Regional Receiving Environment Port Phillip Bay

Figure A-1 Cheetham Wetlands



A-2

Threats


Skeleton Creek catchment has had extensive development (mostly residential housing), built in proximity to the creek system. The urban nature of the catchments when combined with this style of development has the potential to pose a threat to the natural waterways. Therefore, this catchment has been assessed as having a high threat to urban stormwater quality.

Residential Runoff

Skeleton Creek catchment contains a high percentage of residential property within its boundary. Activities such as car washing, unsecured garden waste and incorrect disposal of domestic refuse can all decrease the quality of urban stormwater runoff. The threat of runoff from residential properties within these catchments has been assessed as being a very high urban stormwater threat.

Industrial Runoff

Skeleton Creek catchment contains either minor or no industrial premises. Therefore, the threat of runoff from industrial sites within this catchment has been assessed as being a low urban stormwater threat.

Commercial Runoff

Skeleton Creek catchment contains limited areas of commercial premises, although these have high concentrations of activity. The most specific examples are the Laverton shopping centre and the Central Square shopping centre. Commercial runoff within these catchments has been assessed as having a high threat to urban stormwater quality.


The Skeleton Creek catchment contains within its boundaries numerous major roads, including the Westgate Freeway (Princes Freeway). Many of the secondary roads within this catchment are also utilised by trucking companies for access to the many industrial and warehousing premises in the region. The threat of runoff from these sites and all other industrial premises within these catchments has been assessed as being a very high urban stormwater threat.


Skeleton Creek catchment is considered to contain reasonable opportunities for small-scale building activities. Consequently, the threat of runoff from building sites within these catchments has been assessed as being a moderate urban stormwater threat.

Open Space Runoff

Skeleton Creek catchment contains moderate regions of open space within their respective boundaries. Sites including the Bruce Comben Reserve have the potential to adversely affect the quality of urban stormwater. The threat of runoff from these sites and all other open spaces within these catchments has been assessed as being a moderate urban stormwater threat.



A-3


Skeleton Creek catchment has the potential for small-scale industrial, commercial or residential developments. The available land in this catchment has resulted in it being assessed as having a moderate threat to urban stormwater quality.


Skeleton Creek catchment has been developed more recently than other catchments within Hobsons Bay City Council. Therefore, the likelihood of sewerage failure and illegal connections is low. Consequently, the threat of untreated sewerage entering these catchments has been assessed as being low to urban stormwater quality

Upstream Inflows

Skeleton Creek catchment have moderate percentage of their overall catchments under the jurisdiction of the surrounding councils (Wyndham and Melton) and consequently the water entering Hobsons Bay from these neighbouring councils potentially poses a threat to the water quality of Hobsons Bay. The nature of activities and size of the upstream catchments has resulted in these catchments being assessed as having a high threat to urban stormwater quality.

Boat Ramps

Skeleton Creek has no boat ramps and has consequently been assessed as having no threat from boat ramps.


Skeleton Creek neither contain major industrial sites nor refuse sites. However, there is the possibility of small-scale local contamination. Therefore, these catchments have been assessed as being of low threat to urban stormwater quality



A-4

Laverton Creek

Background

The Laverton Creek Catchment is located in the southwest of the Hobsons Bay. The creek itself extends beyond the boundaries of Hobsons Bay into the neighbouring City of Wyndham. On the banks of the Laverton Creek are numerous reserves and sporting fields including McCormack Park and the A.B. Shaw Reserve. The catchment itself is residential on the Laverton Creek branch and industrial on the Kayes Drain branch with a section of land zoned as being Special Use (significant areas of Industrial use in Slough Estate, the Altona Petrochemical Complex and upstream in Wyndham on Kayes Drain). The Laverton Creek catchment discharges into Port Phillip Bay near Truganina Park. Truganina Swamp, Mt. St Joseph Wetlands and a City West Water purification plant are also within the boundaries of the Laverton Creek Catchment.

Table A-4-2 Laverton Creek Catchment Summary

Catchment Area 1,370.0 Hectares Major Land Uses Residential

Public Park and Recreation

Public Use

Special Use (Predominantly Industrial) Significant Concerns Faunal Habitat

Flood Conveyance

Port Phillip Bay (Receiving Waters) Number of Pipe Outflows 7 Local Receiving Environment Cheetham Wetlands, McCormack Park, Truganina

Parklands, Truganina Swamp Regional Receiving Environment Port Phillip Bay

Threats


Laverton Creek catchment is in a similar situation to those of Skeleton and Cherry, however, the pressure from housing is moderately less than that experienced in the previous catchments. As such, this catchment has been assessed as having a moderate threat to urban stormwater quality.

Residential Runoff

Laverton Creek catchment, like most others in Hobson Bay contain residential areas, however they constitute a smaller percentage of the catchment than the other catchments. The issues associated with residential runoff remain, however. The threat of runoff from residential properties within these catchments has been assessed as being a high urban stormwater threat.



A-5

Figure A-2 Residential and Commercial Runoff on Laverton Creek

Industrial Runoff

The Laverton Creek catchment contains extensive industrial sites within their respective boundaries. The threat of runoff from these sites and all other industrial premises within these catchments has been assessed as being a very high urban stormwater threat.

Commercial Runoff

Laverton Creek catchment contains some of the more moderate commercial regions. Commercial premises within these catchments have been assessed as having a high threat to urban stormwater quality.


The Laverton Creek catchment contains numerous major roads, including the Westgate Freeway (Princes Freeway). Many of the secondary roads within these catchments are also utilised by trucking companies for access to the many industrial and warehousing premises in the region. The threat of runoff from these sites and all other industrial premises within these catchments has been assessed as being a very high urban stormwater threat.


Laverton Creek catchment is considered to contain reasonable opportunities for small-scale building activities, and there are still some large undeveloped areas near the freeway. Consequently, the threat of runoff from building sites within these catchments has been assessed as being a moderate urban stormwater threat.

Open Space Runoff

Laverton Creek catchment contains within its boundaries considerable regions of open space. A.B. Shaw Reserve and McCormack Park are sites of open space that have the potential to impact upon



A-6

urban stormwater quality. The threat of runoff from these sites and all other open spaces within these catchments has been assessed as being a high urban stormwater threat.


The Laverton Creek catchment has the potential for medium-scale industrial, commercial or residential developments. The available land in this catchment has resulted in it being assessed as having a high threat to urban stormwater quality.


Laverton Creek catchment has been developed more recently than those previously mentioned. Therefore, the likelihood of sewerage failure and illegal connections is low. Consequently, the threat of untreated sewerage entering these catchments has been assessed as being low to urban stormwater quality

Upstream Inflows

Laverton Creek catchment has a small percentage of its catchment under the jurisdiction of an adjacent council (Wyndham) and consequently the water entering Hobsons Bay from neighbouring council areas potentially pose a threat to the water quality of Hobsons Bay. The nature of activities and size of the upstream catchments has resulted in these catchments being assessed as having a moderate threat to urban stormwater quality.

Boat Ramps

Laverton Creek has no boat ramps and has consequently been assessed as having no threat from boat ramps.


Laverton Creek catchment has similar histories to Cherry and Kororoit Creek, however as they have occurred on a smaller scale. There are also two sites that have been used for landfill in the past. These catchments have been assessed as being a high threat to urban stormwater quality



A-7

Altona

Background

Altona catchment is located between the Laverton Creek catchment and Cherry Creek Catchment on the coast of Port Phillip Bay. The catchment itself has no natural waterways and runoff is directed though a network of entry pits and pipes to be discharged into Port Phillip Bay. This catchment is predominantly zoned as residential land and does not include the Altona Beach between Webb Street and the Seaholme Jetty.

Table A-4-3 Port Phillip Bay (Altona) Catchment Summary

Catchment Area 283.9 Hectares Major Land Uses Residential

Special Use Significant Concerns Visual Landscape Amenity (including boating)

Tourism Number of Pipe Outflows 2 Local Receiving Environment Regional Receiving Environment Port Phillip Bay

Threats


Altona catchment has no waterways and has consequently been assessed as having no threat from waterway degradation.

Residential Runoff

Altona catchment contains a high percentage of residential property within its boundary. Activities such as car washing, unsecured garden waste and incorrect disposal of domestic refuse can all decrease the quality of urban stormwater runoff. The threat of runoff from residential properties within these catchments has been assessed as being a very high urban stormwater threat.

Industrial Runoff

Altona contains either minor or no industrial premises. Therefore, the threat of runoff from industrial sites within these catchments has been assessed as being a low urban stormwater threat.

Commercial Runoff

Altona catchment only contains minor commercial regions. The threat of runoff from commercial premises within these catchments has been assessed as being a moderate urban stormwater threat.



A-8


Altona does not contain many major road networks or railway lines. Consequently this catchment has been assessed as being of a moderate risk to urban stormwater quality.


Altona catchment is considered to contain reasonable opportunities for small-scale building activities. Consequently, the threat of runoff from building sites within these catchments has been assessed as being a high urban stormwater threat.

Open Space Runoff

Altona catchment contains moderate regions of open space within their respective boundaries. Sites including Logan Reserve have the potential to adversely affect the quality of urban stormwater. The threat of runoff from these sites and all other open spaces within these catchments has been assessed as being a moderate urban stormwater threat.


Altona catchment has the potential for medium-scale industrial, commercial or residential developments. The available land in this catchment has resulted in it being assessed as having a high threat to urban stormwater quality.


Altona catchment has been developed more recently than those previously mentioned. Therefore, the likelihood of sewerage failure and illegal connections is low. Consequently, the threat of untreated sewerage entering these catchments has been assessed as being low to urban stormwater quality

Upstream Inflows

Altona has no upstream inflows and has consequently been assessed as having no threat from upstream inflows.

Boat Ramps

Altona catchment has no boat ramps and has consequently been assessed as having no threat from boat ramps.


Altona neither contains major industrial sites nor refuse sites. However, there is the possibility of small-scale local contamination. Therefore, these catchments have been assessed as being of low threat to urban stormwater quality



A-9

Altona Beach

Background

The Altona Beach catchment covers the primarily residential and public use land that drains to Port Phillip Bay at the Williamstown swimming beaches. This beach is of particular importance as it is one of only two monitored swimming beaches in Hobsons Bay City Council and one of only three in the entire Western suburbs.

Table A-4-4 Altona Beach Catchment Summary


Public Use

Public Conservation and Resource Significant Concerns Recreational Amenity (swimming)


Flood Conveyance

Tourism

Port Phillip Bay (Receiving Waters) Number of Pipe Outflows 12 Local Receiving Environment Regional Receiving Environment Port Phillip Bay

Threats


Altona Beach catchment has no waterways and has consequently been assessed as having no threat from waterway degradation.

Residential Runoff

The Altona Beach catchment contains a high percentage of residential property within its boundaries. Activities such as car washing, unsecured garden waste and incorrect disposal of domestic refuse can all decrease the quality of urban stormwater runoff. The threat of runoff from residential properties within these catchments has been assessed as being a very high urban stormwater threat.

Industrial Runoff

The Altona Beach catchment contains either minor or no industrial premises. Therefore, the threat of runoff from industrial sites within this catchment has been assessed as being a low urban stormwater threat.

Commercial Runoff



A-10

Altona Beach includes some of the main commercial districts within Hobson Bay City Council. The threat of runoff from these sites and all other commercial premises within these catchments has been assessed as being a very high urban stormwater threat.


The Altona Beach catchment contains a number of secondary roads that have the potential to pose a threat to urban stormwater. The threat of runoff from these sites and all other industrial premises within these catchments has been assessed as being a high urban stormwater threat.


The Altona Beach catchment is considered to contain reasonable opportunities for small-scale building activities. Consequently, the threat of runoff from building sites within these catchments has been assessed as being a high urban stormwater threat.

Open Space Runoff

The Altona Beach catchment contains moderate regions of open space within its boundaries. The threat of runoff from these sites and all other open spaces within these catchments has been assessed as being a moderate urban stormwater threat.


The Altona Beach catchment lacks space for large-scale developments. Therefore, these catchments have been assessed as having a low threat to urban stormwater development.


The Altona Beach catchment contains established housing areas and relies on an old and under capacity drainage systems. The likelihood of sewerage pipe failure, seepage and illegal connections is moderate. Consequently, the threat of untreated sewerage entering these catchments has been assessed as being moderate to urban stormwater quality.

Upstream Inflows

The Altona Beach catchment has no upstream inflows and has consequently has been assessed as having no threat from upstream inflows.

Boat Ramps

The Altona Beach Catchment has no boast ramps and consequently has been assessed as having no threat from boat ramps.


The Altona Beach catchment contains neither major industrial sites or refuse sites. However, there is the possibility of small-scale local contamination. Therefore, these catchments have been assessed as being of low threat to urban stormwater quality



A-11

Cherry Creek

Background

Cherry Creek Catchment is a catchment that is contained entirely within the boundaries of Hobsons Bay City Council. The catchment includes land designated as being of industrial, residential and public use. Numerous industrial and warehousing sites are situated within this catchment. The catchment also included Cherry Lake and a swamp conservation zone that includes habitat for the Altona Skipper Butterfly.

Table A-4-5 Cherry Creek Catchment Summary


Special Use

Industrial

Public Use Significant Concerns Visual/Landscape Amenity (including boasting)

Flood Conveyance

Tourism

Port Phillip Bay (Receiving Waters) Number of Pipe Outflows 9 Local Receiving Environment Cherry Lake Regional Receiving Environment Port Phillip Bay

Threats


Cherry Creek catchment has had extensive development (mostly residential housing), built in close proximity to the creek system. The urban nature of the catchments when combined with this style of development has the potential to pose a threat to the natural waterways. Therefore, these catchments have been assessed as having a high threat to urban stormwater quality.

Residential Runoff

Cherry Creek catchment also contains residential areas, however they constitute a smaller percentage of the catchment than the other previously mentioned catchments. The issues associated with residential runoff remain, however. The threat of runoff from residential properties within these catchments has been assessed as being a high urban stormwater threat.

Industrial Runoff

The Cherry Creek catchment contains extensive industrial sites within their respective boundaries. The threat of runoff from these sites and all other industrial premises within these catchments has been assessed as being a very high urban stormwater threat.



A-12

Commercial Runoff

Within the boundaries of the Cherry Creek catchment, there are no significant commercial premises. The threat of runoff from commercial premises within these catchments has been assessed as being a low urban stormwater threat.


Cherry Creek catchment contains within its boundaries numerous major roads, including the Westgate Freeway (Princes Freeway). Many of the secondary roads within these catchments are also utilised by trucking companies for access to the many industrial and warehousing premises in the region. The threat of runoff from these sites and all other industrial premises within this catchment has been assessed as being a very high urban stormwater threat.


Cherry Creek catchment is considered to contain reasonable opportunities for small-scale building activities. Consequently, the threat of runoff from building sites within these catchments has been assessed as being a moderate urban stormwater threat.

Open Space Runoff

Cherry Creek catchment all contain within their respective boundaries considerable regions of open space. J.K. Grant Reserve and Cresser Reserve are sites of open space that have the potential to impact upon urban stormwater quality. The threat of runoff from these sites and all other open spaces within these catchments has been assessed as being a high urban stormwater threat.


Cherry Creek catchment has the potential for large-scale industrial, commercial or residential developments. The available land in this catchment has resulted in it being assessed as having a very high threat to urban stormwater quality.


Cherry Creek catchment has been developed more recently than those previously mentioned. Therefore, the likelihood of sewerage failure and illegal connections is low. Consequently, the threat of untreated sewerage entering these catchments has been assessed as being low to urban stormwater quality

Upstream Inflows

Cherry Creek catchment has part of its overall catchments under the jurisdiction of an adjacent council (Brimbank) and consequently the water entering Hobsons Bay from the neighbouring council potentially poses a threat to the water quality of Hobsons Bay. The nature of activities and size of the upstream catchments has resulted in these catchments being assessed as having a very high threat to urban stormwater quality.

Boat Ramps



A-13

Cherry Creek is one of two catchments within Hobson Bay where boating and fishing are major recreational activities. The threats associated with boat ramps include discharge of hydrocarbons into the waterways, litter and sediment re-suspension, all of which can reduce water quality. Due the number of boat ramps within these two catchments, the catchments have been assessed as being a very high threat to urban stormwater quality.


Cherry Creek catchment has had a long history of industrial usage. Past industrial activities and practices have the potential to create major threats to urban stormwater quality. Contaminated groundwater plumes moving through the groundwater system are an example of this, especially where interchange between the groundwater and surface water occurs. Due the size and nature of previous industrial sites, these catchments have been assessed as being a very high threat to urban stormwater quality.



A-14

Kororoit Creek

Background

Kororoit Creek catchment is the largest within Hobsons Bay and is located centrally within the municipality. The catchment itself extends north into Brimbank City Council and contains a variety of land uses along its length. The creek discharges into Port Phillip Bay near the Altona Coastal Park after meandering its way past some of the heavy industry that is located in Hobsons Bay. Other key land uses within this catchment are residential and public use (in the forms of conservation and resource and park and recreation).

Table A-4-6 Kororoit Creek Catchment Summary

Catchment Area 1651.2 Hectares Major Land Uses Industrial

Residential

Public Conservation and Resource

Special Use

Public Park and Recreation Significant Concerns Faunal Habitat

Port Phillip Bay (Receiving Waters) Number of Pipe Outflows 11 Local Receiving Environment Altona Coastal Park Regional Receiving Environment Port Phillip Bay

Threats


Kororoit Creek catchment has been well developed with industrial and warehousing operations resulting in a significant decrease in the pervious area. This has resulted in increased runoff into the Kororoit Creek and when combined with pressures upon the creek system (recreational access, waterway works) has the potential to cause waterway degradation through increased erosion and sediment movement. Consequently, this catchment has been assessed as having a very high threat to urban stormwater quality.

Residential Runoff

Kororoit Creek catchment contains high percentages of residential property within its boundaries. Activities such as car washing, unsecured garden waste and incorrect disposal of domestic refuse can all decrease the quality of urban stormwater runoff. The threat of runoff from residential properties within this catchment has been assessed as being a very high urban stormwater threat.

Industrial Runoff



A-15

Kororoit Creek catchment contains extensive industrial sites within its boundaries. This catchment in particular is home to some of the Altona petrochemical companies and one of Victoria’s two petroleum refineries. The threat of runoff from these sites and all other industrial premises within these catchments has been assessed as being a very high urban stormwater threat.

Figure A-3 Kororoit Creek in flood with Industry in the background

Commercial Runoff

Kororoit Creek catchment contains some of the more moderate commercial regions. Altona Gate Shopping Centre and ‘The Circle’ shops are some of the numerous commercial premises that pose a threat to urban stormwater quality. Commercial premises within these catchments have been assessed as having a high threat to urban stormwater quality.


The Kororoit Creek catchment contains within its boundaries numerous major roads, including the Westgate Freeway (Princes Freeway). Many of the secondary roads within this catchment are also utilised by trucking companies for access to the many industrial and warehousing premises in the region. The threat of runoff from these sites and all other industrial premises within this catchment has been assessed as being a very high urban stormwater threat.


Kororoit Creek catchment is considered to contain reasonable opportunities for small-scale building activities. Consequently, the threat of runoff from building sites within this catchment has been assessed as being a high urban stormwater threat.

Open Space Runoff

Kororoit Creek catchment contains within their respective boundaries considerable regions of open space. Harris Reserve, Altona Lakes and the J.T. Gray Reserve are all sites of open space that have the potential to impact upon urban stormwater quality. The threat of runoff from these sites and all other open spaces within the catchment has been assessed as being a high urban stormwater threat.



A-16


Kororoit Creek catchment has the potential for medium-scale industrial, commercial or residential developments. The available land in this catchment has resulted in it being assessed as having a high threat to urban stormwater quality.


Kororoit Creek catchment contains approximately 110 sites (60 industrial) that are not connected to the sewerage system and hence rely on septic tanks for effluent disposal. These sites include ‘The Pines’ Scout camp and the Kororoit Creek Fishing Village. The threat of untreated sewerage and sullage entering the Kororoit Creek has been assessed as being high to urban stormwater quality.

Upstream Inflows

Kororoit Creek catchment has a large percentage of its overall catchments under the jurisdiction of the surrounding councils (Brimbank and Melton) and consequently the water entering Hobsons Bay from these neighbouring councils potentially poses a threat to the water quality of Hobsons Bay. The nature of activities and size of the upstream catchments has resulted in these catchments being assessed as having a very high threat to urban stormwater quality.

Boat Ramps

Kororoit Creek catchment whilst having no boat ramps, does contain the local fishing village. The activities of this fishing village pose a similar threat to a boat ramp (through the activities of the fisherman). Therefore, this catchment has been assessed as having a high threat to urban stormwater quality.


Kororoit Creek catchment has had a long history of industrial usage. Past industrial activities and practices have the potential to create major threats to urban stormwater quality. Contaminated groundwater plumes moving through the groundwater system are an example of this, especially where interchange between the groundwater and surface water occurs. Due to the size and nature of current and previous industrial sites, this catchment has been assessed as being a very high threat to urban stormwater quality.



A-17

The Range

Background

The Range catchment consists primarily of a reasonably new housing development built on the old rifle range. The catchment is relatively small compared to others in the municipality; however, it has some very important receiving values. The Range catchment drains into the lakes at the Jawbone Conservation Reserve before entering Port Phillip Bay. The Jawbone Marine Sanctuary protects the coastal regions of Port Phillip Bay in this catchment.

Table A-4-7 The Range Catchment Summary



Comprehensive Development Significant Concerns Faunal Habitat


Tourism Number of Pipe Outflows 3 Local Receiving Environment Jawbone Conservation Reserve, Jawbone Marine

Sanctuary Regional Receiving Environment Port Phillip Bay

Threats


The Range has no waterways and has consequently been assessed as having no threat from waterway degradation.

Residential Runoff

The Range contains a high percentage of residential property within their respective boundaries. Activities such as car washing, unsecured garden waste and incorrect disposal of domestic refuse can all decrease the quality of urban stormwater runoff. The threat of runoff from residential properties within these catchments has been assessed as being a very high urban stormwater threat.

Industrial Runoff

The Range catchment contains either minor or no industrial premises. Therefore, the threat of runoff from industrial sites within these catchments has been assessed as being a low urban stormwater threat.



A-18

Commercial Runoff

The Range catchment only contains minor commercial regions. The threat of runoff from commercial premises within these catchments has been assessed as being a moderate urban stormwater threat.


The Range catchment contains a number of secondary roads that have the potential to pose a threat to urban stormwater. The threat of runoff from these sites and all other industrial premises within these catchments has been assessed as being a high urban stormwater threat.


The Range catchment is one that consists primarily of newly developed and constructed properties and consequently there is a lower prospect of redevelopment. Therefore, the threat of runoff from building sites in this catchment has been assessed as being a low urban stormwater threat.

Open Space Runoff

The Range catchment contains moderate regions of open space within its boundaries. Sites including the Jawbone Conservation Reserve have the potential to adversely affect the quality of urban stormwater. The threat of runoff from these sites and all other open spaces within this catchment has been assessed as being a moderate urban stormwater threat.


The Range is on of the catchments in Hobsons Bay that lacks space for large-scale developments. Therefore, this catchment has been assessed as having a low threat to urban stormwater development.


The Range has no unsewered properties and has consequently been assessed as having no threat from unsewered properties.

Upstream Inflows

The Range has no upstream inflows and has consequently been assessed as having no threat from upstream inflows.

Boat Ramps

The Range has no boat ramps and has consequently been assessed as having no threat from boat ramps.


The Range neither contains major industrial sites nor refuse sites. However, there is the possibility of small-scale local contamination. Therefore, these catchments have been assessed as being of low threat to urban stormwater quality



A-19

Williamstown Beach

Background

The Williamstown Beach catchment covers the primarily residential and public use land that drains to Port Phillip Bay at the Williamstown swimming beaches. This beach is of particular importance as it is one of only two monitored swimming beaches in Hobsons Bay City Council and one of only three in the entire Western suburbs.

Table A-4-8 Williamstown Beach Catchment Summary


Public Use

Public Conservation and Resource Significant Concerns Recreational Amenity (swimming)


Flood Conveyance

Tourism

Port Phillip Bay (Receiving Waters) Number of Pipe Outflows 6 Local Receiving Environment Regional Receiving Environment Port Phillip Bay

Figure A-4 Williamstown Beach



A-20

Threats


Williamstown Beach catchment has no waterways and has consequently been assessed as having no threat from waterway degradation.

Residential Runoff

The Williamstown Beach catchment contains a high percentage of residential property within its boundaries. Activities such as car washing, unsecured garden waste and incorrect disposal of domestic refuse can all decrease the quality of urban stormwater runoff. The threat of runoff from residential properties within these catchments has been assessed as being a very high urban stormwater threat.

Industrial Runoff

The Williamstown Beach catchment contains either minor or no industrial premises. Therefore, the threat of runoff from industrial sites within this catchment has been assessed as being a low urban stormwater threat.

Commercial Runoff

Williamstown Beach catchment includes some of the main commercial districts within Hobson Bay City Council. The threat of runoff from these sites and all other commercial premises within these catchments has been assessed as being a very high urban stormwater threat.


The Williamstown Beach catchment contains a number of secondary roads that have the potential to pose a threat to urban stormwater. The threat of runoff from these sites and all other industrial premises within these catchments has been assessed as being a high urban stormwater threat.


The Williamstown Beach catchment is considered to contain reasonable opportunities for small-scale building activities. Consequently, the threat of runoff from building sites within these catchments has been assessed as being a high urban stormwater threat.

Open Space Runoff

The Williamstown Beach catchment contains moderate regions of open space within its boundaries. The threat of runoff from these sites and all other open spaces within these catchments has been assessed as being a moderate urban stormwater threat.



A-21


The Williamstown Beach catchment lacks space for large-scale developments. Therefore, these catchments have been assessed as having a low threat to urban stormwater development.


The Williamstown Beach catchment contains established housing areas and relies on an old and under capacity drainage systems. The likelihood of sewerage pipe failure, seepage and illegal connections is moderate. Consequently, the threat of untreated sewerage entering these catchments has been assessed as being moderate to urban stormwater quality.

Upstream Inflows

The Williamstown Beach catchment has no upstream inflows and has consequently been assessed as having no threat from upstream inflows.

Boat Ramps

The Williamstown Beach has a fishing club boat ramp nearby, which has the potential to adversely impact upon urban stormwater quality. Due to the limited extent of the use of this ramp the catchment has been assessed as having a moderate threat to urban stormwater quality.


The Williamstown Beach catchment contains neither major industrial sites or refuse sites. However, there is the possibility of small-scale local contamination. Therefore, these catchments have been assessed as being of low threat to urban stormwater quality



A-22

Williamstown/Newport

Background

The Williamstown/Newport Catchment is located in the southeast section of Hobsons Bay City Council. It extends along the coast from the Jawbone Conservation Sanctuary to ScienceWorks (not including Williamstown Beach). It includes the Ferguson St, Nelson Pl, Mason St and Melbourne Road commercial precincts along with the residential properties between Melbourne Road and the coast. Elements of foreshore region although contained within this catchment are under the control of the Ports of Melbourne Corporation. The catchment includes the Point Gellibrand Coastal Heritage Park and Greenwich Bay within its boundaries.

Table A-4-9 Williamstown/Newport Catchment Summary


Industrial

Business


Public Park and Recreation

Special Use

Port of Melbourne Significant Concerns Cultural Heritage


Flood Conveyance

Tourism Number of Pipe Outflows 17 Local Receiving Environment Point Gellibrand Coastal Heritage Park, Greenwich

Bay, Greenwich Reserve Regional Receiving Environment Port Phillip Bay

Threats


The Williamstown/Newport catchment has no waterways and has consequently been assessed as having no threat from waterway degradation.

Residential Runoff

The Williamstown/Newport catchment contains high percentages of residential property within its boundaries. Activities such as car washing, unsecured of garden waste and incorrect disposal of domestic refuse can all decrease the quality of urban stormwater runoff. The threat of runoff from



A-23

residential properties within this catchment has been assessed as being a very high urban stormwater threat.

Industrial Runoff

The Williamstown/Newport catchment whilst being predominantly residential, does contain some industrial premises in the northeast region and the shipyards in the south. The threat of runoff from these sites and all other industrial premises within this catchment has been assessed as being a high urban stormwater threat.

Commercial Runoff

The Williamstown Newport catchment includes some of the main commercial districts within Hobsons Bay City Council. The shopping strip along Ferguson St and the commercial precinct along Nelson Place are two of the key commercial threats to urban stormwater quality. The threat of runoff from these sites and all other commercial premises within these catchments has been assessed as being a very high urban stormwater threat.

Figure A-5 Nelson Place in Williamstown


The Williamstown/Newport catchment contains a number of secondary roads that have the potential to pose a threat to urban stormwater. Combined with these secondary roads, this catchment also includes locomotive maintenance, storage and restoration facilities. The threat of runoff from these sites and all other industrial premises within these catchments has been assessed as being a high urban stormwater threat.


The Williamstown/Newport catchment is considered to contain reasonable opportunities for small-scale building activities. Consequently, the threat of runoff from building sites within these catchments has been assessed as being a high urban stormwater threat.



A-24

Open Space Runoff

The Williamstown/Newport catchments all contain within their respective boundaries considerable regions of open space. Sites including the Williamstown Cricket Ground and Greenwich Reserve have the potential to adversely impact upon the water quality of the surrounding waterways. The threat of runoff from these sites and all other open spaces within these catchments has been assessed as being a high urban stormwater threat.


The Williamstown/Newport catchment lacks space for large-scale developments. Therefore, these catchments have been assessed as having a low threat to urban stormwater development.


The Williamstown/Newport catchment contains relatively old housing and relies on an old and under capacity drainage systems. The likelihood of sewerage pipe failure, seepage and illegal connections is moderate. Consequently, the threat of untreated sewerage entering these catchments has been assessed as being moderate to urban stormwater quality

Upstream Inflows

The Williamstown/Newport catchment has no upstream inflows and has consequently been assessed as having no threat from upstream inflows.

Boat Ramps

Williamstown/Newport catchment is the second of two catchments within Hobsons Bay City Council where boating and fishing are major recreational activities. The Williamstown/Newport catchment is home to Royal Yacht Club of Victoria, various other yacht and boating clubs, and a recreational boat ramp at ‘the Warmies’. The threats associated with boat ramps include discharge of hydrocarbons into the waterways, litter and sediment re-suspension, all of which can reduce water quality. Due the number of boat ramps within this catchment, they have been assessed as being a very high threat to urban stormwater quality.


Williamstown/Newport catchment whilst not containing any major industrial sites, does include the old Newport tip site and locomotive manufacturing premises. Consequently, this catchment has been assessed as being a moderate threat to urban stormwater quality.



A-25

Stony Creek

Background

Stony Creek catchment is located in the northeast section of Hobsons Bay; however, the bulk of the catchment is located in the neighbouring council of Maribyrnong. The catchment consists of primarily residential and industrial land, however, the Ports of Melbourne Corporation does control some of the land along the coast. Stony Creek Backwash is contained within this catchment.

Table A-4-10 Stony Creek Catchment Summary


Industrial

Port of Melbourne Significant Concerns Flood Conveyance

Port Phillip Bay (Receiving Waters) Number of Pipe Outflows 1 Local Receiving Environment Stony Creek Park (The Backwash) Regional Receiving Environment Port Phillip Bay

Figure A-6 Stony Creek Backwash



A-26

Threats


The Stony Creek catchment has had extensive development, both residential and industrial, built in close proximity to the creek. The urban nature of the catchment when combined with this style of development has the potential to pose a threat to the natural waterways. Therefore, these catchments have been assessed as having a high threat to urban stormwater quality.

Residential Runoff

The Stony Creek catchment contains a high percentage of residential property within its boundaries. Activities such as car washing, unsecured of garden waste and incorrect disposal of domestic refuse can all decrease the quality of urban stormwater runoff. The threat of runoff from residential properties within these catchments has been assessed as being a very high urban stormwater threat.

Industrial Runoff

The Stony Creek catchment contains extensive industrial sites within its boundaries. The threat of runoff from these sites and all other industrial premises within the catchment has been assessed as being a very high urban stormwater threat.

Commercial Runoff

The Stony Creek catchment contains some of the more moderate commercial regions. Commercial premises within these catchments have been assessed as having a high threat to urban stormwater quality.


The Stony Creek catchment contains within its boundaries numerous major roads, including the Westgate Freeway (Princes Freeway). Many of the secondary roads within these catchments are also utilised by trucking companies for access to the many industrial and warehousing premises in the region. The threat of runoff from these sites and all other industrial premises within the catchment has been assessed as being a very high urban stormwater threat.


The Stony Creek catchment is considered to contain reasonable opportunities for small-scale building activities. Consequently, the threat of runoff from building sites within these catchments has been assessed as being a high urban stormwater threat.

Open Space Runoff

Stony Creek catchment contains moderate regions of open space within its boundaries. Sites including the Westgate Golf Course have the potential to adversely affect the quality of urban stormwater. The threat of runoff from these sites and all other open spaces within the catchment has been assessed as being a moderate urban stormwater threat.



A-27


Stony Creek is one of the catchments within Hobsons Bay that lacks space for large-scale developments. Therefore, these catchments have been assessed as having a low threat to urban stormwater development.


Stony Creek catchment contains relatively old housing and relies on an old and under capacity drainage systems. The likelihood of sewerage pipe failure, seepage and illegal connections is moderate. Consequently, the threat of untreated sewerage entering these catchments has been assessed as being moderate to urban stormwater quality

Upstream Inflows

Stony Creek catchment has a large percentage of its overall catchment under the jurisdiction of the surrounding councils (Maribyrnong and Brimbank) and consequently the water entering Hobsons Bay from these neighbouring councils potentially poses a threat to the water quality of Hobsons Bay. The nature of activities and size of the upstream catchments has resulted in these catchments being assessed as having a very high threat to urban stormwater quality.

Boat Ramps

Stony Creek has no boat ramps and has consequently been assessed as having no threat from boat ramps.


Stony Creek catchment has a similar history to Cherry and Kororoit Creek, however as it has occurred on a smaller scale, this catchments have been assessed as being a high threat to urban stormwater quality

RISK ANALYSIS RESULTS


B-1

APPENDIX B: RISK ANALYSIS RESULTS



B-2

Skeleton Creek Wat

erw

ay D

egra

datio

n

Res

iden

tial R

unof

f

Indu

stria

l Run

off

Com

mer

ical

Run

off

Maj

or R

oad

/ Rai

l Run

off

Bui

ldin

g Si

te R

unof

f

Ope

n Sp

ace

Run

off

Res

iden

tial /

Indu

stria

l D

evel

opm

ent

Uns

ewer

ed P

rope

rties

Ups

tream

Inflo

ws

Boa

t Ram

ps

Con

tam

inat

ed L

and

/ G

roun

dwat

er

3.0 4.0 1.0 3.0 4.0 2.0 2.0 2.0 1.0 3.0 1.0

4.0 2.0 3.0 2.0 3.0 1.0 2.0 3.0 3.0 4.0 1.0 3.0 Aquatic Habitat 2.0

24.0 16.0 6.0 12.0 24.0 4.0 8.0 12.0 6.0 24.0 6.0

3.0 2.0 3.0 2.0 2.0 1.0 2.0 3.0 3.0 4.0 1.0 3.0 Riparian Habitat 2.0

18.0 16.0 6.0 12.0 16.0 4.0 8.0 12.0 6.0 24.0 6.0

4.0 2.0 3.0 2.0 2.0 1.0 2.0 3.0 3.0 4.0 1.0 3.0

Envi

ronm

enta

l

Faunal Habitat 4.0

48.0 32.0 12.0 24.0 32.0 8.0 16.0 24.0 12.0 48.0 12.0

2.0 2.0 2.0 2.0 2.0 1.0 1.0 3.0 2.0 1.0 1.0 2.0

Cul

tura

l

Cultural Heritage 2.0

12.0 16.0 4.0 12.0 16.0 4.0 4.0 12.0 4.0 6.0 4.0

2.0 4.0 3.0 4.0 3.0 3.0 2.0 2.0 4.0 4.0 4.0 2.0 Recreational Amenity (Swimming) 3.0

6.0 48.0 9.0 36.0 36.0 18.0 12.0 12.0 12.0 36.0 6.0

2.0 4.0 4.0 4.0 4.0 3.0 2.0 2.0 3.0 4.0 4.0 2.0 Am

enity

Visual / Landscape Amenity (including boating) 4.0

24.0 64.0 16.0 48.0 64.0 24.0 16.0 16.0 12.0 48.0 8.0

4.0 2.0 2.0 2.0 2.0 1.0 1.0 2.0 1.0 2.0 1.0 1.0

Hyd

raul

ic

Flood Conveyance 4.0

48.0 32.0 8.0 24.0 32.0 8.0 8.0 16.0 4.0 24.0 4.0

4.0 3.0 3.0 3.0 3.0 2.0 1.0 1.0 1.0 4.0 4.0 1.0

Econ

omic

Tourism 1.0

12.0 12.0 3.0 9.0 12.0 4.0 2.0 2.0 1.0 12.0 1.0

3.0 3.0 3.0 3.0 3.0 2.0 1.0 2.0 3.0 4.0 4.0 2.0

Rec

eivi

ng

Wat

ers

Port Phillip Bay 4.0

36.0 48.0 12.0 36.0 48.0 16.0 8.0 16.0 12.0 48.0 8.0



B-3

Laverton Creek Wat

erw

ay D

egra

datio

n

Res

iden

tial R

unof

f

Indu

stria

l Run

off

Com

mer

ical

Run

off

Maj

or R

oad

/ Rai

l Run

off

Bui

ldin

g Si

te R

unof

f

Ope

n Sp

ace

Run

off

Res

iden

tial /

Indu

stria

l D

evel

opm

ent

Uns

ewer

ed P

rope

rties

Ups

tream

Inflo

ws

Boa

t Ram

ps

Con

tam

inat

ed L

and

/ G

roun

dwat

er

2.0 3.0 4.0 3.0 4.0 2.0 2.0 3.0 1.0 2.0 3.0

4.0 2.0 3.0 2.0 3.0 1.0 2.0 3.0 3.0 4.0 1.0 3.0 Aquatic Habitat 2.0

16.0 12.0 24.0 12.0 24.0 4.0 8.0 18.0 6.0 16.0 18.0


12.0 12.0 24.0 12.0 16.0 4.0 8.0 18.0 6.0 16.0 18.0

4.0 2.0 3.0 2.0 2.0 1.0 2.0 3.0 3.0 4.0 1.0 3.0

Envi

ronm

enta

l

Faunal Habitat 4.0

32.0 24.0 48.0 24.0 32.0 8.0 16.0 36.0 12.0 32.0 36.0

2.0 2.0 2.0 2.0 2.0 1.0 1.0 3.0 2.0 1.0 1.0 2.0

Cul

tura

l


8.0 12.0 16.0 12.0 16.0 4.0 4.0 18.0 4.0 4.0 12.0

2.0 4.0 3.0 4.0 3.0 3.0 2.0 2.0 4.0 4.0 4.0 2.0 Recreational Amenity (swimming) 1.0

4.0 12.0 12.0 12.0 12.0 6.0 4.0 6.0 4.0 8.0 6.0

2.0 4.0 4.0 4.0 4.0 3.0 2.0 2.0 3.0 4.0 4.0 2.0 Am

enity


12.0 36.0 48.0 36.0 48.0 18.0 12.0 18.0 9.0 24.0 18.0

4.0 2.0 2.0 2.0 2.0 1.0 1.0 2.0 1.0 2.0 1.0 1.0

Hyd

raul

ic


32.0 24.0 32.0 24.0 32.0 8.0 8.0 24.0 4.0 16.0 12.0

4.0 3.0 3.0 3.0 3.0 2.0 1.0 1.0 1.0 4.0 4.0 1.0

Econ

omic

Tourism 1.0

8.0 9.0 12.0 9.0 12.0 4.0 2.0 3.0 1.0 8.0 3.0

3.0 3.0 3.0 3.0 3.0 2.0 1.0 2.0 3.0 4.0 4.0 2.0

Rec

eivi

ng

Wat

ers


24.0 36.0 48.0 36.0 48.0 16.0 8.0 24.0 12.0 32.0 24.0



B-4

Altona Wat

erw

ay D

egra

datio

n

Res

iden

tial R

unof

f

Indu

stria

l Run

off

Com

mer

ical

Run

off

Maj

or R

oad

/ Rai

l Run

off

Bui

ldin

g Si

te R

unof

f

Ope

n Sp

ace

Run

off

Res

iden

tial /

Indu

stria

l D

evel

opm

ent

Uns

ewer

ed P

rope

rties

Ups

tream

Inflo

ws

Boa

t Ram

ps

Con

tam

inat

ed L

and

/ G

roun

dwat

er

4.0 1.0 2.0 2.0 3.0 2.0 3.0 1.0 1.0

4.0 2.0 3.0 2.0 3.0 1.0 2.0 3.0 3.0 4.0 1.0 3.0 Aquatic Habitat

3.0 2.0 3.0 2.0 2.0 1.0 2.0 3.0 3.0 4.0 1.0 3.0 Riparian Habitat

4.0 2.0 3.0 2.0 2.0 1.0 2.0 3.0 3.0 4.0 1.0 3.0

Envi

ronm

enta

l

Faunal Habitat 2.0

16.0 6.0 8.0 8.0 6.0 8.0 18.0 6.0 6.0

2.0 2.0 2.0 2.0 2.0 1.0 1.0 3.0 2.0 1.0 1.0 2.0

Cul

tura

l


8.0 2.0 4.0 4.0 3.0 2.0 9.0 2.0 2.0


48.0 9.0 24.0 18.0 27.0 12.0 18.0 12.0 6.0

2.0 4.0 4.0 4.0 4.0 3.0 2.0 2.0 3.0 4.0 4.0 2.0 Am

enity


64.0 16.0 32.0 32.0 36.0 16.0 24.0 12.0 8.0

4.0 2.0 2.0 2.0 2.0 1.0 1.0 2.0 1.0 2.0 1.0 1.0

Hyd

raul

ic


24.0 6.0 12.0 12.0 9.0 6.0 18.0 3.0 3.0

4.0 3.0 3.0 3.0 3.0 2.0 1.0 1.0 1.0 4.0 4.0 1.0

Econ

omic

Tourism 3.0

36.0 9.0 18.0 18.0 18.0 6.0 9.0 3.0 3.0

3.0 3.0 3.0 3.0 3.0 2.0 1.0 2.0 3.0 4.0 4.0 2.0

Rec

eivi

ng

Wat

ers


48.0 12.0 24.0 24.0 24.0 8.0 24.0 12.0 8.0



B-5

Altona Beach Wat

erw

ay D

egra

datio

n

Res

iden

tial R

unof

f

Indu

stria

l Run

off

Com

mer

ical

Run

off

Maj

or R

oad

/ Rai

l Run

off

Bui

ldin

g Si

te R

unof

f

Ope

n Sp

ace

Run

off

Res

iden

tial /

Indu

stria

l D

evel

opm

ent

Uns

ewer

ed P

rope

rties

Ups

tream

Inflo

ws

Boa

t Ram

ps

Con

tam

inat

ed L

and

/ G

roun

dwat

er

4.0 1.0 4.0 2.0 3.0 2.0 1.0 2.0 1.0

4.0 2.0 3.0 2.0 3.0 1.0 2.0 3.0 3.0 4.0 1.0 3.0 Aquatic Habitat 3.0

24.0 9.0 24.0 18.0 9.0 12.0 9.0 18.0 9.0


8.0 3.0 8.0 4.0 3.0 4.0 3.0 6.0 3.0

4.0 2.0 3.0 2.0 2.0 1.0 2.0 3.0 3.0 4.0 1.0 3.0

Envi

ronm

enta

l

Faunal Habitat 2.0

16.0 6.0 16.0 8.0 6.0 8.0 6.0 12.0 6.0

2.0 2.0 2.0 2.0 2.0 1.0 1.0 3.0 2.0 1.0 1.0 2.0

Cul

tura

l


16.0 4.0 16.0 8.0 6.0 4.0 6.0 8.0 4.0


64.0 12.0 64.0 24.0 36.0 16.0 8.0 32.0 8.0

2.0 4.0 4.0 4.0 4.0 3.0 2.0 2.0 3.0 4.0 4.0 2.0 Am

enity


64.0 16.0 64.0 32.0 36.0 16.0 8.0 24.0 8.0

4.0 2.0 2.0 2.0 2.0 1.0 1.0 2.0 1.0 2.0 1.0 1.0

Hyd

raul

ic


32.0 8.0 32.0 16.0 12.0 8.0 8.0 8.0 4.0

4.0 3.0 3.0 3.0 3.0 2.0 1.0 1.0 1.0 4.0 4.0 1.0

Econ

omic

Tourism 4.0

48.0 12.0 48.0 24.0 24.0 8.0 4.0 8.0 4.0

3.0 3.0 3.0 3.0 3.0 2.0 1.0 2.0 3.0 4.0 4.0 2.0

Rec

eivi

ng

Wat

ers


48.0 12.0 48.0 24.0 24.0 8.0 8.0 24.0 8.0



B-6

Cherry Creek Wat

erw

ay D

egra

datio

n

Res

iden

tial R

unof

f

Indu

stria

l Run

off

Com

mer

ical

Run

off

Maj

or R

oad

/ Rai

l Run

off

Bui

ldin

g Si

te R

unof

f

Ope

n Sp

ace

Run

off

Res

iden

tial /

Indu

stria

l D

evel

opm

ent

Uns

ewer

ed P

rope

rties

Ups

tream

Inflo

ws

Boa

t Ram

ps

Con

tam

inat

ed L

and

/ G

roun

dwat

er

3.0 3.0 4.0 1.0 4.0 2.0 2.0 4.0 1.0 4.0 4.0 4.0

4.0 2.0 3.0 2.0 3.0 1.0 2.0 3.0 3.0 4.0 1.0 3.0 Aquatic Habitat 3.0

36.0 18.0 36.0 6.0 36.0 6.0 12.0 36.0 9.0 48.0 12.0 36.0


27.0 18.0 36.0 6.0 24.0 6.0 12.0 36.0 9.0 48.0 12.0 36.0

4.0 2.0 3.0 2.0 2.0 1.0 2.0 3.0 3.0 4.0 1.0 3.0

Envi

ronm

enta

l

Faunal Habitat 3.0

36.0 18.0 36.0 6.0 24.0 6.0 12.0 36.0 9.0 48.0 12.0 36.0

2.0 2.0 2.0 2.0 2.0 1.0 1.0 3.0 2.0 1.0 1.0 2.0

Cul

tura

l


6.0 6.0 8.0 2.0 8.0 2.0 2.0 12.0 2.0 4.0 4.0 8.0


12.0 24.0 24.0 8.0 24.0 12.0 8.0 16.0 8.0 32.0 32.0 16.0

2.0 4.0 4.0 4.0 4.0 3.0 2.0 2.0 3.0 4.0 4.0 2.0 Am

enity


24.0 48.0 64.0 16.0 64.0 24.0 16.0 32.0 12.0 64.0 64.0 32.0

4.0 2.0 2.0 2.0 2.0 1.0 1.0 2.0 1.0 2.0 1.0 1.0

Hyd

raul

ic


48.0 24.0 32.0 8.0 32.0 8.0 8.0 32.0 4.0 32.0 16.0 16.0

4.0 3.0 3.0 3.0 3.0 2.0 1.0 1.0 1.0 4.0 4.0 1.0

Econ

omic

Tourism 3.0

36.0 27.0 36.0 9.0 36.0 12.0 6.0 12.0 3.0 48.0 48.0 12.0

3.0 3.0 3.0 3.0 3.0 2.0 1.0 2.0 3.0 4.0 4.0 2.0

Rec

eivi

ng

Wat

ers


36.0 36.0 48.0 12.0 48.0 16.0 8.0 32.0 12.0 64.0 64.0 32.0



B-7

Kororoit Creek Wat

erw

ay D

egra

datio

n

Res

iden

tial R

unof

f

Indu

stria

l Run

off

Com

mer

ical

Run

off

Maj

or R

oad

/ Rai

l Run

off

Bui

ldin

g Si

te R

unof

f

Ope

n Sp

ace

Run

off

Res

iden

tial /

Indu

stria

l D

evel

opm

ent

Uns

ewer

ed P

rope

rties

Ups

tream

Inflo

ws

Boa

t Ram

ps

Con

tam

inat

ed L

and

/ G

roun

dwat

er

4.0 4.0 4.0 3.0 4.0 3.0 2.0 3.0 3.0 4.0 3.0 4.0

4.0 2.0 3.0 2.0 3.0 1.0 2.0 3.0 3.0 4.0 1.0 3.0 Aquatic Habitat 3.0

48.0 24.0 36.0 18.0 36.0 9.0 12.0 27.0 27.0 48.0 9.0 36.0


36.0 24.0 36.0 18.0 24.0 9.0 12.0 27.0 27.0 48.0 9.0 36.0

4.0 2.0 3.0 2.0 2.0 1.0 2.0 3.0 3.0 4.0 1.0 3.0

Envi

ronm

enta

l

Faunal Habitat 4.0

64.0 32.0 48.0 24.0 32.0 12.0 16.0 36.0 36.0 64.0 12.0 48.0

2.0 2.0 2.0 2.0 2.0 1.0 1.0 3.0 2.0 1.0 1.0 2.0

Cul

tura

l


24.0 24.0 24.0 18.0 24.0 9.0 6.0 27.0 18.0 12.0 9.0 24.0


8.0 16.0 12.0 12.0 12.0 9.0 4.0 6.0 12.0 16.0 12.0 8.0

2.0 4.0 4.0 4.0 4.0 3.0 2.0 2.0 3.0 4.0 4.0 2.0 Am

enity


24.0 48.0 48.0 36.0 48.0 27.0 12.0 18.0 27.0 48.0 36.0 24.0

4.0 2.0 2.0 2.0 2.0 1.0 1.0 2.0 1.0 2.0 1.0 1.0

Hyd

raul

ic


64.0 32.0 32.0 24.0 32.0 12.0 8.0 24.0 12.0 32.0 12.0 16.0

4.0 3.0 3.0 3.0 3.0 2.0 1.0 1.0 1.0 4.0 4.0 1.0

Econ

omic

Tourism 2.0

32.0 24.0 24.0 18.0 24.0 12.0 4.0 6.0 6.0 32.0 24.0 8.0

3.0 3.0 3.0 3.0 3.0 2.0 1.0 2.0 3.0 4.0 4.0 2.0

Rec

eivi

ng

Wat

ers


48.0 48.0 48.0 36.0 48.0 24.0 8.0 24.0 36.0 64.0 48.0 32.0



B-8

The Range Wat

erw

ay D

egra

datio

n

Res

iden

tial R

unof

f

Indu

stria

l Run

off

Com

mer

ical

Run

off

Maj

or R

oad

/ Rai

l Run

off

Bui

ldin

g Si

te R

unof

f

Ope

n Sp

ace

Run

off

Res

iden

tial /

Indu

stria

l D

evel

opm

ent

Uns

ewer

ed P

rope

rties

Ups

tream

Inflo

ws

Boa

t Ram

ps

Con

tam

inat

ed L

and

/ G

roun

dwat

er

4.0 1.0 2.0 2.0 1.0 2.0 1.0 1.0

4.0 2.0 3.0 2.0 3.0 1.0 2.0 3.0 3.0 4.0 1.0 3.0 Aquatic Habitat 3.0

24.0 9.0 12.0 18.0 3.0 12.0 9.0 9.0


24.0 9.0 12.0 12.0 3.0 12.0 9.0 9.0

4.0 2.0 3.0 2.0 2.0 1.0 2.0 3.0 3.0 4.0 1.0 3.0

Envi

ronm

enta

l

Faunal Habitat 4.0

32.0 12.0 16.0 16.0 4.0 16.0 12.0 12.0

2.0 2.0 2.0 2.0 2.0 1.0 1.0 3.0 2.0 1.0 1.0 2.0

Cul

tura

l


24.0 6.0 12.0 12.0 3.0 6.0 9.0 6.0


16.0 3.0 8.0 6.0 3.0 4.0 2.0 2.0

2.0 4.0 4.0 4.0 4.0 3.0 2.0 2.0 3.0 4.0 4.0 2.0 Am

enity


64.0 16.0 32.0 32.0 12.0 16.0 8.0 8.0

4.0 2.0 2.0 2.0 2.0 1.0 1.0 2.0 1.0 2.0 1.0 1.0

Hyd

raul

ic


24.0 6.0 12.0 12.0 3.0 6.0 6.0 3.0

4.0 3.0 3.0 3.0 3.0 2.0 1.0 1.0 1.0 4.0 4.0 1.0

Econ

omic

Tourism 2.0

24.0 6.0 12.0 12.0 4.0 4.0 2.0 2.0

3.0 3.0 3.0 3.0 3.0 2.0 1.0 2.0 3.0 4.0 4.0 2.0

Rec

eivi

ng

Wat

ers


36.0 9.0 18.0 18.0 6.0 6.0 6.0 6.0



B-9

Williamstown Beach Wat

erw

ay D

egra

datio

n

Res

iden

tial R

unof

f

Indu

stria

l Run

off

Com

mer

ical

Run

off

Maj

or R

oad

/ Rai

l Run

off

Bui

ldin

g Si

te R

unof

f

Ope

n Sp

ace

Run

off

Res

iden

tial /

Indu

stria

l D

evel

opm

ent

Uns

ewer

ed P

rope

rties

Ups

tream

Inflo

ws

Boa

t Ram

ps

Con

tam

inat

ed L

and

/ G

roun

dwat

er

4.0 1.0 4.0 2.0 3.0 2.0 1.0 2.0 2.0 1.0

4.0 2.0 3.0 2.0 3.0 1.0 2.0 3.0 3.0 4.0 1.0 3.0 Aquatic Habitat 3.0

24.0 9.0 24.0 18.0 9.0 12.0 9.0 18.0 6.0 9.0


8.0 3.0 8.0 4.0 3.0 4.0 3.0 6.0 2.0 3.0

4.0 2.0 3.0 2.0 2.0 1.0 2.0 3.0 3.0 4.0 1.0 3.0

Envi

ronm

enta

l

Faunal Habitat 2.0

16.0 6.0 16.0 8.0 6.0 8.0 6.0 12.0 4.0 6.0

2.0 2.0 2.0 2.0 2.0 1.0 1.0 3.0 2.0 1.0 1.0 2.0

Cul

tura

l


16.0 4.0 16.0 8.0 6.0 4.0 6.0 8.0 4.0 4.0


64.0 12.0 64.0 24.0 36.0 16.0 8.0 32.0 32.0 8.0

2.0 4.0 4.0 4.0 4.0 3.0 2.0 2.0 3.0 4.0 4.0 2.0 Am

enity


64.0 16.0 64.0 32.0 36.0 16.0 8.0 24.0 32.0 8.0

4.0 2.0 2.0 2.0 2.0 1.0 1.0 2.0 1.0 2.0 1.0 1.0

Hyd

raul

ic


32.0 8.0 32.0 16.0 12.0 8.0 8.0 8.0 8.0 4.0

4.0 3.0 3.0 3.0 3.0 2.0 1.0 1.0 1.0 4.0 4.0 1.0

Econ

omic

Tourism 4.0

48.0 12.0 48.0 24.0 24.0 8.0 4.0 8.0 32.0 4.0

3.0 3.0 3.0 3.0 3.0 2.0 1.0 2.0 3.0 4.0 4.0 2.0

Rec

eivi

ng

Wat

ers


48.0 12.0 48.0 24.0 24.0 8.0 8.0 24.0 32.0 8.0



B-10

Williamstown / Newport W

ater

way

Deg

rada

tion

Res

iden

tial R

unof

f

Indu

stria

l Run

off

Com

mer

ical

Run

off

Maj

or R

oad

/ Rai

l Run

off

Bui

ldin

g Si

te R

unof

f

Ope

n Sp

ace

Run

off

Res

iden

tial /

Indu

stria

l D

evel

opm

ent

Uns

ewer

ed P

rope

rties

Ups

tream

Inflo

ws

Boa

t Ram

ps

Con

tam

inat

ed L

and

/ G

roun

dwat

er

4.0 3.0 4.0 3.0 3.0 2.0 1.0 2.0 4.0 2.0

4.0 2.0 3.0 2.0 3.0 1.0 2.0 3.0 3.0 4.0 1.0 3.0 Aquatic Habitat 1.0

8.0 9.0 8.0 9.0 3.0 4.0 3.0 6.0 4.0 6.0


8.0 9.0 8.0 6.0 3.0 4.0 3.0 6.0 4.0 6.0

4.0 2.0 3.0 2.0 2.0 1.0 2.0 3.0 3.0 4.0 1.0 3.0

Envi

ronm

enta

l

Faunal Habitat 2.0

16.0 18.0 16.0 12.0 6.0 8.0 6.0 12.0 8.0 12.0

2.0 2.0 2.0 2.0 2.0 1.0 1.0 3.0 2.0 1.0 1.0 2.0

Cul

tura

l


32.0 24.0 32.0 24.0 12.0 8.0 12.0 16.0 16.0 16.0


48.0 27.0 48.0 27.0 27.0 12.0 6.0 24.0 48.0 12.0

2.0 4.0 4.0 4.0 4.0 3.0 2.0 2.0 3.0 4.0 4.0 2.0 Am

enity


64.0 48.0 64.0 48.0 36.0 16.0 8.0 24.0 64.0 16.0

4.0 2.0 2.0 2.0 2.0 1.0 1.0 2.0 1.0 2.0 1.0 1.0

Hyd

raul

ic


32.0 24.0 32.0 24.0 12.0 8.0 8.0 8.0 16.0 8.0

4.0 3.0 3.0 3.0 3.0 2.0 1.0 1.0 1.0 4.0 4.0 1.0

Econ

omic

Tourism 4.0

48.0 36.0 48.0 36.0 24.0 8.0 4.0 8.0 64.0 8.0

3.0 3.0 3.0 3.0 3.0 2.0 1.0 2.0 3.0 4.0 4.0 2.0

Rec

eivi

ng

Wat

ers


36.0 27.0 36.0 27.0 18.0 6.0 6.0 18.0 48.0 12.0



B-11

Stony Creek Wat

erw

ay D

egra

datio

n

Res

iden

tial R

unof

f

Indu

stria

l Run

off

Com

mer

ical

Run

off

Maj

or R

oad

/ Rai

l Run

off

Bui

ldin

g Si

te R

unof

f

Ope

n Sp

ace

Run

off

Res

iden

tial /

Indu

stria

l D

evel

opm

ent

Uns

ewer

ed P

rope

rties

Ups

tream

Inflo

ws

Boa

t Ram

ps

Con

tam

inat

ed L

and

/ G

roun

dwat

er

3.0 4.0 4.0 3.0 4.0 3.0 2.0 1.0 2.0 4.0 3.0

4.0 2.0 3.0 2.0 3.0 1.0 2.0 3.0 3.0 4.0 1.0 3.0 Aquatic Habitat 2.0

24.0 16.0 24.0 12.0 24.0 6.0 8.0 6.0 12.0 32.0 18.0


18.0 16.0 24.0 12.0 16.0 6.0 8.0 6.0 12.0 32.0 18.0

4.0 2.0 3.0 2.0 2.0 1.0 2.0 3.0 3.0 4.0 1.0 3.0

Envi

ronm

enta

l

Faunal Habitat 2.0

24.0 16.0 24.0 12.0 16.0 6.0 8.0 6.0 12.0 32.0 18.0

2.0 2.0 2.0 2.0 2.0 1.0 1.0 3.0 2.0 1.0 1.0 2.0

Cul

tura

l


12.0 16.0 16.0 12.0 16.0 6.0 4.0 6.0 8.0 8.0 12.0


6.0 16.0 12.0 12.0 12.0 9.0 4.0 2.0 8.0 16.0 6.0

2.0 4.0 4.0 4.0 4.0 3.0 2.0 2.0 3.0 4.0 4.0 2.0 Am

enity


18.0 48.0 48.0 36.0 48.0 27.0 12.0 6.0 18.0 48.0 18.0

4.0 2.0 2.0 2.0 2.0 1.0 1.0 2.0 1.0 2.0 1.0 1.0

Hyd

raul

ic


48.0 32.0 32.0 24.0 32.0 12.0 8.0 8.0 8.0 32.0 12.0

4.0 3.0 3.0 3.0 3.0 2.0 1.0 1.0 1.0 4.0 4.0 1.0

Econ

omic

Tourism 2.0

24.0 24.0 24.0 18.0 24.0 12.0 4.0 2.0 4.0 32.0 6.0

3.0 3.0 3.0 3.0 3.0 2.0 1.0 2.0 3.0 4.0 4.0 2.0

Rec

eivi

ng

Wat

ers


36.0 48.0 48.0 36.0 48.0 24.0 8.0 8.0 24.0 64.0 24.0

COMPARISON OF VALUES, THREATS AND RISKS IN THE 1999 PLAN AND THE CURRENT PLAN


C-1

APPENDIX C: COMPARISON OF VALUES, THREATS AND RISKS IN THE 1999 PLAN AND THE CURRENT PLAN

Values

The values utilised in the 99 Plan are similar to those adopted for this Plan, with the comparison seen below.

Table C-1 Values Comparison of 1999 and 2005 Plans 99 Plan 05 Plan

Cultural Heritage Cultural Heritage Economic Tourism Tourism Public Health & Safety Recreation and Leisure Recreational Amenity - swimming Visual/landscape Visual/landscape Amenity (including boating) Instream Habitat Aquatic Habitat Wetlands (grasslands) Riparian Habitat Flora & Fauna Faunal Habitat Flood Protection Flood Conveyance Foreshore Ecology Foreshore Amenity Water Resource Receiving Waters Port Phillip Bay

The standard values utilised in stormwater management planning have been rationalised since 1999, although there scope to vary these for each individual plan according to local needs. In this case the value ‘Recreational Amenity’ has been expended into two values, with a specific one for swimming, given the importance of primary contact recreation at the city’s two beaches, and the associated stringent requirements for water quality for this use. The other values have been dropped as they are not considered to be directly applicable to stormwater impacts, or are covered in the other values.

Threats

The 99 Plan used the term ‘activities’ to describe those land uses or activities that threaten stormwater, whereas the current convention is to use the term ‘Threats’. Essentially the two categories contain similar elements as can be seen in the table below.

Table C-2 Threats Comparison of 1999 and 2005 Plan 99Plan 05 Plan

Construction & development Building site runoff Residential/industrial development

Industrial Industrial runoff Transport Major road/rail runoff Sewer overflows Unsewered properties Illegal connections (domestic) Land use changes Illegal dumping Dog poo Littering



C-2

Rubbish collection and disposal Recreation Open space runoff

Boat ramps External catchment activities Upstream inflows Management of stormwater system Waterway degradation Residential Residential runoff Syringes Retail/business Commercial runoff Contaminated Land/Groundwater

Definition of Sub-Areas

The sub-areas defined in the two plans differ. In the 99 Plan three sub-areas were defined for the purposes of undertaking the risk analysis, and values and activities (threats) were defined for these. These sub-areas were east, central and west sections of the Municipality, however it has not been possible to obtain the locations of the boundaries of these sections.

For the current Plan it has been decided to define sub-areas based on drainage catchments, which enables strategies and actions to be developed to manage specific threats from the stormwater flowing into those areas.

Risks

A comparison of the priority risks identified in the 99 Plan and that calculated for the new plan is shown in the table below.

Table C-3 Risk Comparison of 1999 and 2005 Plan 99 Plan 05 Plan

Threat Location Threat Location Residential construction & development

• Wyndham Growth Corridor

• Knightsbridge Av, Laverton

• Point Cook Road • Melbourne Rd,

Newport • Kororoit Creek Rd

(old BP site)

Littering • Rubbish collection & disposal

• Williamstown town center

• Central Square Shopping Centre; Merton St

• Altona Gate • Aviation Rd,

Laverton

Commercial runoff • Williamstown/Altona Beaches

• Williamstown/Newport

Industry • APC, Kororoit Creek Rd

• Grieve Pde • Douglas Pde • Nelson Place

Industrial runoff • Cherry Creek



C-3

shipbuilders Transport • Kororoit Creek Rd

• Princes Freeway • Westgate Freeway

Major road/rail runoff • Cherry Creek • Skeleton Creek

Recreation • Littering at Williamstown & Altona Beaches

• Upstream inflows • Cherry Creek • Kororoit Creek • Stony Creek

• Boat ramps • Cherry Creek • Williamstown/Newport

• Waterway degradation • Kororoit Creek • Residential runoff • Port Phillip Bay

• Skeleton Creek • The Range • Williamstown/Altona

Beaches • Williamstown/Newport

• Contaminated Land/Groundwater

• Kororoit Creek

IMPLEMENTATION OF ACTIONS FROM THE 1999 SWMP


D-1

APPENDIX D: IMPLEMENTATION OF ACTIONS FROM THE 1999 SWMP

Hobsons Bay Stormwater Projects Supported by VSAP

1. Altona Tip Wetland Development (2003)

Re-development of open water channel into series of 3 water quality improvement ponds to treat run-off prior to it entering Port Phillip Bay. This project was developed after Hobsons Bay Council identified the concrete lined open channel which carries stormwater from Polly Woodside Drive and Altona Meadows to Laverton Creek and into Port Phillip Bay for re-development into a series of three water quality improvement ponds to treat stormwater runoff prior to discharge into Laverton Creek and Port Phillip Bay. Funded by EPA Victoria as part of the Victorian Stormwater Action Program 2002/03/04.

2. Williamstown Beach Gross Pollutant Trap Installation

Installation of gross pollutant trap at Williamstown Beach and pit cover stencilling.

This project led to the installation of a gross pollutant trap at Williamstown Beach, which was anticipated to benefit the community two-fold; by removing pollutants prior to entering Port Phillip Bay and by providing a visual reminder to beach users about stormwater related issues. This reminder was enhanced by stencilling the pit covers and through other information media. Funded by EPA Victoria as part of the Victorian Stormwater Action Program 2002/03.

3. Drain Stencilling Awareness Program

School and community pilot program - development of logo and slogan, drain stencilling, media promotion. This pilot program involved the community and schools of Hobsons Bay creating a logo and slogan to be used as visual reminders of stormwater issues. Media promotion and drain stencilling packs were made available across six western regions. Also created was a poster promoting general practices to prevent stormwater pollution. Funded by EPA Victoria as part of the Victorian Stormwater Action Program 2002/03.

4. Catchment Development Impact Project - Guidelines for Site Management, WSUD and planning.

Project Partners: Brimbank City Council, Wyndham City Council, Victorian Stormwater Action Program

SMP Guidelines, WSUD guidelines, responses report developed as part of Catchment Development Impact Project

The Catchment Development Impact Project has built on the Stormwater Management Plans prepared for the Cities of Hobsons Bay, Brimbank and Wyndham by developing planning scheme, local law and enforcement requirements to assist achieve the objectives of best practice stormwater management. The program also included an Education/Training Program addressing the second



D-2

major component of the Catchment Development Impact Project, which is to develop the education and training material to support the Statutory Responses detailed as the first component of the Project. Guidelines were developed to assist local government address the impacts new and existing developments have on bayside municipalities - Site Management Guidelines, WSUD Guidelines and Statutory Responses Report.

5. Catchment Development Impact Project - Stormwater Education Brochures - industry & households

Project Partners: Brimbank City Council, Wyndham City Council, Victorian Stormwater Action Program

Brochures developed for industry and household to improve awareness of behaviours impacting on on stormwater quality as part of a broader education and awareness project.

6. Catchment Development Impact Project - Stormwater Education Posters

Publication

Brimbank City Council, Wyndham City Council, Victorian Stormwater Action Program

Posters developed to promote the impacts of construction and community behaviours on stormwater quality as part of a broader education and awareness project. Refer to Stormwater Education Brochures

7. Catchment Development Impact Project Education & Training Program Report

Report

Brimbank City Council, Wyndham City Council, Victorian Stormwater Action Program

The Catchment Development Impact Project has built on the Stormwater Management Plans prepared for the Cities of Hobsons Bay, Brimbank and Wyndham by developing planning scheme, local law and enforcement requirements to assist achieve the objectives of best practice stormwater management. This Education/Training Program report addresses the second major component of the Catchment Development Impact Project, which is to develop the education and training material to support the Statutory Responses detailed as the first component of the Project."

8. Local Laws and Education/ Catchment Development Impact Project

Case Study

Victorian Stormwater Action Program, Brimbank City Council, Wyndham City Council

Addressing impacts new and existing developments are having on bayside municipalities.

This project was designed to address the impact new and existing developments were having on waterways within the municipalities of Hobsons Bay, Brimbank and Wyndham. The local community was concerned about the impact development was having on waterways in relation to increased run-off, sedimentation, litter and pollution from substances such as oils and detergents. The



D-3

first stage involved a review of each council's planning scheme provisions, local laws, planning permit conditions and enforcement requirements and procedures. Statements are now in the Municipal Strategic Statement and are consistent across the three municipalities. Guidelines and an education and training program were developed in addition to posters and brochures on stormwater management for residents and industries. The second stage of the project involved educating council officers, land developers and builders on the existing and proposed legislation which included a seminar on 30/09/02. This communication is ongoing and Hobsons Bay has adopted changes to Local Law 2 giving council more controls on stormwater quality. The Site Management Plan Guidelines are now a referred document and builders are required to comply with them (a fine of up to $2000 applies for non-compliance). There are also litter control measures such as the requirement for compulsory fencing and lidded bins. The associated website is currently only live on Hobsons Bay City Council's site (www.hobsons.vic.gov.au, then click on the butterfly to access the stormwater section). Available is a summary and a report (make these both internal links) which incorporate proposed specific amendments to planning schemes, local laws and planning permit conditions to address building and construction sites. Also included are guidelines for developing site management plans as part of the development approvals process for Hobsons Bay, Wyndham and Brimbank City Councils. Funded by EPA Victoria as part of the Victorian Stormwater Action Program 2001/02.

RISK ANALYSIS RESULTS D-1


APPENDIX D: RISK ANALYSIS RESULTS

The Risk Analysis Results are included as Appendix B of the Priority Issues Paper (included as Appendix C of this volume). Consequently the Risk Analysis Results have not been repeated in this Appendix.

RISK MANAGEMENT ACTION SCREENING E-1


APPENDIX E: RISK MANAGEMENT ACTION SCREENING



Table E-1 Management Element Screening Results for Risk Strategy 1

Residential Runoff

IssuesHobsons Bay contains extensive areas of residential housing. The popularity of living close to the city, combined with the attractive features of the region (swimming beaches, coastal views, etc) have resulted in heavy development across the council and in general, large percentages of impervious area.PollutantsRunoff from residential properties can contain pollutants including Increased flow, sediment, nutrients, litter, oxygen depleting material, hydrocarbons, pathogens, trace metals and pesticides

Element Type Strategy Elements

Litte

r

Coa

rse

Sedi

men

t

Fine

Sed

imen

t

Oils

and

Gre

ase

Deo

xyge

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g M

ater

ials

Nut

rient

s

Path

ogen

s

Flow

Man

agem

ent

Comment

Rec

omm

ende

d

Literature/Guideline Development and Distribution Consider Opportunities

Stormwater Management Education Workshops Consider Opportunities

Demonstration Projects Consider Opportunities

Long Term Individual/Organisation Consultation Consider Opportunities

Media Release Consider Opportunities

Signage Limited Benefit

Community & Special Interest Group Limited Benefit

Business Stakeholder Groups & Committees Not Applicable to Threat

Street Sweeping Already undertaken by HBCC

Waste & Refuse Collection Already undertaken by HBCC

Waterway Rehabilitation & Revegetation Already undertaken, but additional opportunities exist

Develop & Implement Site Specific EMP's Not Relevant to Threat - Education and Awareness more appropriate

Develop & Implement Site Specific Sed & Erosion Control Plans Not Relevant to Threat - Education and Awareness more appropriate

Waste Management Program Development Not Relevant to Threat - Education and Awareness more appropriate

Stormwater Management Guidelines Consider Opportunities

Waterway Management Strategy Development Consider Opportunities

Spill Prevention and Containment Plans Not Relevant to Threat - Education and Awareness more appropriate

Swales Consider Opportunities

Porous Pavements Limited Benefit

Rainwater storage and reuse (eg: Tanks, Rainwater Gardens) Limited Benefit - Opportunities should be considered

Stormwater Infiltration Measures Consider Opportunities

Filter Strips Consider Opportunities

Screening Devices Limited Benefit

Artificial Wetlands New Wetlands Unlikely (Space Constraints) - Improve existing wetlands

Gross Pollutant Traps Consider Opportunities

Drainage Inlet Traps Limited Benefit

Sedimentation Basins Limited Benefit (Space Constraints)

Instream Floating Debris & Litter Booms Not Relevant to Threat

Oil and Grease Interceptors Not Relevant to Threat

Flow Detention Structures (Basins) Limited Benefit

Litter Audits Limited Benefit

Monitoring and Data Collection Consider Opportunities

Financial Incentives (eg. Rate Rebates) Consider Opportunities

Audit and Inspection Limited Benefit

Infringement Notification and Fines Limited Benefit

Stra

tegi

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nd P

lans

Information & Data Collection

Regulation and Enforcement

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Upstream Inflows

Issues

The creek and waterway systems that exist in Hobsons Bay have catchments that extend beyond the council boundaries. Consequently, council have little or no control as to the quantity or quality of water in the waterways inside council boundaries. Systems like Kororoit Creek, Cherry Creek, Skeleton Creek and Stony Creek all have catchments extending into neighbouring councils and their characteristics will be determined partly by activities upstream.PollutantsUpstream inflows could contain pollutants including sediments, litter, nutrients and pathogens.


Litte

r

Coa

rse

Sedi

men

t

Fine

Sed

imen

t

Toxi

cant

s

Oils

and

Gre

ase

Deo

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natin

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ater

ials

Nut

rient

s

Path

ogen

s

Flow

Man

agem

ent

Comment

Rec

omm

ende

d

Literature/Guideline Development and Distribution Not Relevant to Threat - Threat external to HBCC

Stormwater Management Education Workshops Not Relevant to Threat - Threat external to HBCC

Demonstration Projects Not Relevant to Threat - Threat external to HBCC

Long Term Individual/Organisation Consultation Not Relevant to Threat - Threat external to HBCC


Signage Not Relevant to Threat - Threat external to HBCC

Community & Special Interest Group Consider Opportunities

Business Stakeholder Groups & Committees Not Relevant to Threat - Threat external to HBCC

Street Sweeping Not Relevant to Threat - Threat external to HBCC

Waste & Refuse Collection Not Relevant to Threat - Threat external to HBCC

Waterway Rehabilitation & Revegetation Would need to be a "whole of waterway approach"

Develop & Implement Site Specific EMP's Not Relevant to Threat - Threat external to HBCC

Develop & Implement Site Specific Sed & Erosion Control Plans Not Relevant to Threat - Threat external to HBCC

Waste Management Program Development Not Relevant to Threat - Threat external to HBCC


Waterway Management Strategy Development Consider Opportunities - Cooperation with upstream councils and MW

Spill Prevention and Containment Plans Not Relevant to Threat - Threat external to HBCC

Swales

Porous Pavements

Rainwater storage and reuse (eg: Tanks, Rainwater Gardens)Stormwater Infiltration Measures

Filter Strips

Screening Devices

Artificial Wetlands

Gross Pollutant Traps

Drainage Inlet Traps

Sedimentation Basins

Instream Floating Debris & Litter Booms

Oil and Grease Interceptors

Flow Detention Structures (Basins)

Litter Audits Not Relevant to Threat - Threat external to HBCC


Financial Incentives (eg. Rate Rebates) Not Relevant to Threat - Threat external to HBCC

Audit and Inspection Not Relevant to Threat - Threat external to HBCC

Infringement Notification and Fines Not Relevant to Threat - Threat external to HBCC

Stra

tegi

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nd P

lans



Educ

atio

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d Aw

aren

ess

Sour

ce

Con

trols

Wat

er S

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Urb

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esig

n Te

chni

ques

Water Sensitive Treatment Urban Design Techniques would need to be undertaken in the neighbouring councils, not HBCC.




Commercial Runoff

IssuesHobsons Bay contains a number of commercial precincts within its boundaries. Some, including the Nelson Place shops are considered to be tourist attractions. These precincts have high patronage and are generally located within close proximity to local waterways, main drains or the coastline. PollutantsRunoff from commercial premises can contain sediment, nutrients, litter, oxygen depleting material, hydrocarbons, pathogens, trace metals and surfactants


Litte

r

Coa

rse

Sedi

men

t

Fine

Sed

imen

t

Oils

and

Gre

ase

Deo

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natin

g M

ater

ials

Nut

rient

s

Path

ogen

s

Flow

Man

agem

ent

Comment

Rec

omm

ende

d





Media Release Limited Benefit

Signage Site Specific Signage may provide benefit


Business Stakeholder Groups & Committees Consider Opportunities



Waterway Rehabilitation & Revegetation Not relevant to threat

Develop & Implement Site Specific EMP's Consider Opportunities

Develop & Implement Site Specific Sed & Erosion Control Plans Should be included as part of site specific EMP

Waste Management Program Development Should be included as part of site specific EMP


Waterway Management Strategy Development Not relevant to threat

Spill Prevention and Containment Plans Should be included as part of site specific EMP



Rainwater storage and reuse (eg: Tanks, Rainwater Gardens) Limited Benefit - Opportunities should be considered




Artificial Wetlands Space Constraints limit effectiveness

Gross Pollutant Traps May be appropriate - Limited Benefit

Drainage Inlet Traps Consider Opportunities

Sedimentation Basins Space Constraints limit effectiveness

Instream Floating Debris & Litter Booms Not relevant to threat

Oil and Grease Interceptors Limited Benefit - Only relevant to particular sites

Flow Detention Structures (Basins) Not relevant to threat

Litter Audits Consider Opportunities

Monitoring and Data Collection Limited Benefit




Stra

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Industrial Runoff

IssuesHobsons Bay City Council contains within its boundaries one the largest and most concentration petrochemical complexes in Australia. Petroleum refineries, car plants, polymer plants and chemical production facilities all exist within close proximity to the local waterways. PollutantsRunoff from industrial sites can contain pollutants including Increased flow, sediment, nutrients, litter, oxygen depleting materials, hydrocarbons, pathogens, trace metals, pesticides and surfactants


Litte

r

Coa

rse

Sedi

men

t

Fine

Sed

imen

t

Toxi

cant

s

Oils

and

Gre

ase

Deo

xyge

natin

g M

ater

ials

Nut

rient

s

Path

ogen

s

Flow

Man

agem

ent

Comment

Rec

omm

ende

d






Signage Site specific signage may provide benefit

Community & Special Interest Group Not Relevant to Threat


Street Sweeping Not Relevant to Threat

Waste & Refuse Collection Not Relevant to Threat

Waterway Rehabilitation & Revegetation Not Relevant to Threat


Develop & Implement Site Specific Sed & Erosion Control Plans Should be included as part of a site specific EMP

Waste Management Program Development Should be included as part of a site specific EMP


Waterway Management Strategy Development Not Relevant to Threat

Spill Prevention and Containment Plans Must be included as part of a site specific EMP



Rainwater storage and reuse (eg: Tanks, Rainwater Gardens) Consider Opportunities - Reuse especially



Screening Devices Consider Opportunities

Artificial Wetlands Consider Opportunities



Sedimentation Basins Consider Opportunities


Oil and Grease Interceptors Limited Benefit - Site Specific

Flow Detention Structures (Basins) Not Relevant to Threat

Litter Audits Not Relevant to Threat

Monitoring and Data Collection Not Relevant to Threat


Audit and Inspection Should be already undertaken by EPA

Infringement Notification and Fines Should be already undertaken by EPA

Stra

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nd P

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Edu

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IssuesAs a consequence of possessing major industrial, manufacturing and warehousing premises, Hobsons Bay also contains an extensive road and rail network. Hobsons Bay also contains locomotive maintenance, storage and restoration facilities. PollutantsRunoff from both road and rail can contribute pollutants including sediments, litter, trace metals and hydrocarbons into the stormwater.


Litt

er

Coa

rse

Sedi

men

t

Fine

Sed

imen

t

Toxi

cant

s

Oils

and

Gre

ase

Path

ogen

s

Flow

Man

agem

ent

Comment

Rec

omm

ende

d

Literature/Guideline Development and Distribution Not Relevant to Threat - Onus on VicRoads and VicTrack not HBCC

Stormwater Management Education Workshops Not Relevant to Threat - Onus on VicRoads and VicTrack not HBCC

Demonstration Projects Not Relevant to Threat - Onus on VicRoads and VicTrack not HBCC

Long Term Individual/Organisation Consultation Not Relevant to Threat - Onus on VicRoads and VicTrack not HBCC

Media Release Not Relevant to Threat - Onus on VicRoads and VicTrack not HBCC

Signage Not Relevant to Threat - Onus on VicRoads and VicTrack not HBCC

Community & Special Interest Group Not Relevant to Threat - Onus on VicRoads and VicTrack not HBCC

Business Stakeholder Groups & Committees Not Relevant to Threat - Onus on VicRoads and VicTrack not HBCC

Street Sweeping Potential exists, although unlikely due to safety concerns




Develop & Implement Site Specific Sed & Erosion Control Plans Should be considered as part of a site specific EMP

Waste Management Program Development Not Relevant to Threat



Spill Prevention and Containment Plans Consider Opportunities


Porous Pavements Unlikely to be viable

Rainwater storage and reuse (eg: Tanks, Rainwater Gardens) Not Relevant to Threat

Stormwater Infiltration Measures Unlikely to be viable



Artificial Wetlands Consider Opportunities



Sedimentation Basins Consider Opportunities


Oil and Grease Interceptors Limited Benefit

Flow Detention Structures (Basins) Consider Opportunities


Monitoring and Data Collection Limited Benefit

Financial Incentives (eg. Rate Rebates) Not Relevant to Threat

Audit and Inspection Not Relevant to Threat

Infringement Notification and Fines Should already be undertaken by EPA

Stra

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nd P

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Educ

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d Aw

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Sour

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Con

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Wat

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Urb

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Boat Ramps

Issues

Hobson Bay is a coastal council and consequently draws both fisherman and boaters to a number of fishing spots and boat ramps along the coastline. Activities undertaken at both fishing spots and boat ramps have the potential to impact upon the quality of both stormwater and receiving waters.PollutantsBoat Ramps can contribute pollutants including sediment, oxygen depleting materials, litter, oils and greases, trace metals and toxic substances


Litte

r

Coa

rse

Sedi

men

t

Fine

Sed

imen

t

Toxi

cant

s

Oils

and

Gre

ase

Deo

xyge

natin

g M

ater

ials

Comment

Rec

omm

ende

d


Stormwater Management Education Workshops Limited Benefit


Long Term Individual/Organisation Consultation Not Relevant to Threat


Signage Site specific signage may provide limited benefit




Waste & Refuse Collection Should already be undertaken by HBCC



Develop & Implement Site Specific Sed & Erosion Control Plans Not Relevant to Threat

Waste Management Program Development Should be included as part of a site specific EMP



Spill Prevention and Containment Plans Should be included as part of a site specific EMP

Swales Limited Benefit

Porous Pavements Not Relevant to Threat

Rainwater storage and reuse (eg: Tanks, Rainwater Gardens) Not Relevant to Threat



Screening Devices Not Relevant to Threat

Artificial Wetlands Not Relevant to Threat

Gross Pollutant Traps Limited Benefit

Drainage Inlet Traps Consider Opportunities

Sedimentation Basins Not Relevant to Threat


Oil and Grease Interceptors Not Relevant to Threat

Flow Detention Structures (Basins) Not Relevant to Threat

Litter Audits Limited Benefit

Monitoring and Data Collection Not Relevant to Threat




Stra

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Edu

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Issues

Hobsons Bay City Council contains a number of waterways within its boundaries, including: Skeleton Creek, Cherry Creek, Kororoit Creek, Laverton Creek and Stony Creek. The increasing development of Hobsons Bay has placed pressure on these natural waterways as housing, roads and infrastructure encroach on floodplains and consequently water quality declines. Weed infestation, eroded and unstable riparian zones, loss of natural vegetation and poorly controlled access can all exacerbate the problemsPollutantsWaterway degradation can contribute pollutants including sediments, nutrients and oxygen depleting substances


Litte

r

Coa

rse

Sedi

men

t

Fine

Sed

imen

t

Toxi

cant

s

Oils

and

Gre

ase

Deo

xyge

natin

g M

ater

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Nut

rient

s

Path

ogen

s

Flow

Man

agem

ent

Comment

Rec

omm

ende

d

Literature/Guideline Development and Distribution Limited Benefit

Stormwater Management Education Workshops Limited Benefit

Demonstration Projects Limited Benefit



Signage Limited Benefit but may be effective at key locations.





Waterway Rehabilitation & Revegetation Consider Opportunities as part of a waterway management strategy


Develop & Implement Site Specific Sed & Erosion Control Plans Should be included as part of a waterway management strategy

Waste Management Program Development Not Relevant to Threat

Stormwater Management Guidelines Not Relevant to Threat

Waterway Management Strategy Development Consider Opportunities

Spill Prevention and Containment Plans Not Relevant to Threat

Swales

Porous Pavements


Filter Strips

Screening Devices

Artificial Wetlands










Audit and Inspection Not Relevant to Threat

Infringement Notification and Fines Consider Opportunities

Stra

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nd P

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Edu

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Water Sensitive Urban Design Techniques can be used to improve the quality of runoff from sources and consequently their respective

effectiveness against this threat is not relevant. The use of this treatment is considered in other strategies.





Issues

The Hobsons Bay region has had a long history of industrial use. Old industrial premises and waste disposal sites may have contaminated both soil and groundwater allowing contaminants to possibly enter the local waterways. PollutantsContaminated soil and water may contribute pollutants including oxygen depleting substance, pathogens, hydrocarbons and toxic substances.


Toxi

cant

s

Oils

and

Gre

ase

Deo

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Path

ogen

s

Comment

Rec

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Media Release Limited Benefit - Would only provide information to community

Signage Limited Benefit - Would only provide information to community

Community & Special Interest Group Limited Benefit - Would only provide information to community

Business Stakeholder Groups & Committees Limited Benefit - Would only provide information to community





Develop & Implement Site Specific Sed & Erosion Control Plans Should be included as part of a site specific EMP

Waste Management Program Development Consider Opportunities



Spill Prevention and Containment Plans Consider Opportunities

Swales

Porous Pavements


Filter Strips

Screening Devices

Artificial Wetlands










Audit and Inspection Consider Opportunities

Infringement Notification and Fines Consider Opportunities

Contaminated Land/Groundwater in the municipality already exists. Further contamination should not occur due to regulations, however, treatment techniques have already been identified in Strategy Four.

These treatment measures will have no impact on contamination that already exists.

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MANAGEMENT ACTION OPPORTUNITIES F-1


APPENDIX F: MANAGEMENT ACTION OPPORTUNITIES



Table F-1 Priority Risk Issue 1, Management Action Opportunities

Risk Management Strategy 1 Priority Risk Issue 1 –Residential Runoff The strategy responds to the risk of residential runoff within the City of Hobsons Bay. The strategy focuses heavily of education and awareness of the community to stormwater related issues and provides opportunities for involvement in local community groups, education sessions and consultation. Due to the broad scale of the threat, it also targets individual homeowners and residents through media releases and literature distribution, whilst also encouraging good stormwater practice through the implementation of a rate rebate scheme. A number of Water Sensitive Urban Design (WSUD) treatment techniques have also been included.

Cost Action Number Action Code Management Action Description

Capital Ongoing Responsibility & Assistance

Extent of Application

1 PRI1-SP-02

Stormwater Management Guidelines An extension of the Stormwater Management Plan, these guidelines will allow Council to have a detailed knowledge of stormwater management, techniques that can be implemented and requirements that they can impose upon contractors (erosion control) and other individuals involved with stormwater. Significant cost savings could be achieved through the adaptation of existing stormwater management guidelines (developed as part of the Victorian Stormwater Action Program) to ensure relevance to Hobsons Bay City Council. These tailored guidelines should include local examples and pictures to ensure a connection with the target audience. The target audience includes developers, designers, local and town planners and Hobsons Bay City Council. The development of these guidelines should allow HBCC, developers and designers to ensure that new residential properties or developments minimise the risk to the local environment caused by stormwater runoff from residential properties.

$50,000 $5,000 Council Municipality

2 PRI1-WSUD-02

Rainwater Storage and Reuse A technique that can be employed to reduce stormwater runoff and consequently contaminant runoff from the residential properties. Council could encourage residents to make use of available subsidies through State Government and local water retailers to reduce their demand for potable water. Council could lead the uptake for rainwater storage and reuse through the application of rainwater storage at council premises and the use of recycled water on council gardens and sporting ovals.

$15,000 $5,000 Council Local

3 PRI1-EA-01

Literature/Guideline Development and Distribution Develop information and guidelines regarding the requirements of residential properties in relation to urban stormwater. Information could be provided about what services Council provides (rubbish collection, street sweeping) and what should be done by the residents to reduce their impact on the local stormwater (not overfilling bins, washing cars on grass, etc). As with the stormwater management guidelines (PRI1-SP-02), significant cost savings can be achieved through the adaptation of existing resources, guidelines and related materials to make them applicable with the local setting. Such an action should be targeting all residents and homeowners within the City of Hobson Bay. The target audience for this action would be all the residents within the municipality.


4 PRI1-SP-01b

Beach Precinct Improvement Strategy Both Williamstown and Altona Beaches require protection from the adverse impacts of contaminated stormwater from both residential and commercial runoff, including syringes. A clean stormwater strategy prepared for both beach catchments will enable a strategic examination of the options for improving stormwater, including WSUD, enforcement and education and information. Opportunities to be investigated for this strategy include structural measures such as diversion of stormwater away from beach drain outlets, fostering infiltration and bioretention upstream of drain outlets, trapping in pits at commercial areas as well as in the vicinity of the beaches, and use of GPTs.

$10,000 Council

5 PRI1-SP-01a Develop and Implement Site Specific EMP’s $20,000 $7,500 Council and Local



Develop site-specific environmental management plans for key residential areas in order to manage and reduce their impact upon the stormwater. Through the Victorian Stormwater Action Plan, Melbourne Water, the Land Development Industry and 3 local councils, formulated a site EMP kit. This EMP kit can be adapted to suit the requirements of both Council and differing requirements of each site and will results in cost savings for Council. The site specific EMP’s would be most appropriate for future medium to large scale (limited opportunities) residential developments (or redevelopments).

EPA

6 PRI1-EA-03

Demonstration Projects Actively promote the design and implement a number of water sensitive urban design projects to address a range of priority risk issues across the entire municipality. The purpose of such projects is to show Council and stakeholders the benefits of water sensitive urban design in a number of situations and addressing a number of issues. Whilst a number of demonstration projects already exists in neighbouring councils, it is important that Hobsons Bay City Council use this action to implement water sensitive urban design techniques in highly visible regions within the municipality. This allows both residents and Council to view and benefits of such designs in everyday life.


7 PRI1-EA-04

Long Term Individual/Organisation Consultation Liase with land holders, developers and resident groups on how residential areas contribute to poor stormwater quality and what can be done to improve the impact on the local receiving environments. This action is best combined the PRI1-EA-01 and PRI1-EA-02 and could be used as follow up exercise between Council and resident groups to determine the effectiveness of education programs and observe any resulting changes in behaviour or attitude towards stormwater management.


8 PRI1-EA-05

Media Release A media release aimed specifically at the residents and including information about what they can do around the home to improve stormwater quality. Any media release should be linked in with PRI1-EA-01 to ensure maximum benefit from the literature/guidelines development and distribution.

$7,500 Council Municipality

9 PRI1-EA-02

Stormwater Management Education Workshops Conduct a workshop for Council workers and interested stakeholders, community representatives and community groups to educate them regarding the issues related to stormwater and the actions that can be undertaken to minimise the impact. Education workshops could be built into the Environment Resource Centre workshop program to enable easy integration into existing education programs.


10 PRI1-WSUD-04

Filter Strips Implement filter strips where possible and appropriate. Filter strips are simply strips of vegetation or grass that stormwater flows through in order to drain to the receiving environment. Open drains along the beach may potentially be diverted through a filter strip before entering the bay. Filter strips could be implemented in areas where overland flow of stormwater is expected (between coastal car-parks and the Bay, along foreshore zones, etc)


11 PRI1-WSUD-03

Stormwater Infiltration Measures Implement stormwater infiltration measures where possible and appropriate. Stormwater infiltration measures can be implemented at the end of swales or open drains. These measures allow for the infiltration of water into the ground and remove pollutants from the stormwater. These measures can include either infiltration pits or bio-retention systems. Such measures can easily be retrofitted into existing nature strips or traffic islands.


12 PRI1-IDC-01

Monitoring and Data Collection The current waterway monitoring program within the municipality is limited to two sites on Skeleton Creek and Kororoit Creek and a third site is located outside the municipal boundary on Stony Creek. This monitoring program could be expanded to include both Laverton and Cherry Creeks to enable at least one monitoring site on each of Hobsons Bay’s major creeks. The EPA also currently monitors both Williamstown and Altona Beaches during the summer months to ensure water quality is safe for swimming (primary contact). This monitoring program could be expanded to include regions where secondary contact is likely (ie: yacht clubs and boat ramps) Additional

$150,000 $25,000 Melbourne Water, EPA and Council

Waterways



monitoring that can be undertaken by Council could include the monitoring of litter quantities removed from the various GPTS and beaches throughout the municipality and qualitative assessments of creek condition (visible scums, oils, sediments, etc). Such a qualitative assessment program could easily involve local schools and community groups and could be used as an education tool. It is important to realise that monitoring programs can be difficult and expensive to operate and maintain. In order to make best use of available funds, the aims and objectives of any monitoring program need to be determined to ensure adequate and useful outcomes are achieved.

13 PRI1-WSUD-01

Swales Implement swales where possible and appropriate. Swales can be used instead of conventional kerb and channel drainage. Swales facilitate the removal of pollutants and reduce runoff by encouraging infiltration. Existing table drains can easily be converted into swales to achieve and increased water treatment efficiency. Along roads where no drainage has been provided, a swale can fairly easily be added (provided there is enough space), to treat the road runoff.


14 PRI1-SC-01

Waterway Rehabilitation and Revegetation Rehabilitation and Revegetation of the local waterways will improve their capacity to remove and deal with contaminants. Improving the natural characteristics of the local waterways will improve the quality of the overall waterway and allow it to better deal with stormwater entering the system.

$500,000 $50,000

Melbourne Water,

Council and Community

Groups

Waterways

PRI= Priority Issue, EA = Education and Awareness, SC = Source Controls, SP = Strategies and Plans, WSUD = Water Sensitive Urban Design Techniques, IDC = Information and Data Collection and RE =

Regulation and Enforcement.




Risk Management Strategy 2 Priority Risk Issue 2 – Upstream Inflows The strategy responds to the risk of upstream inflows into the various creeks and waterways of Hobsons Bay City Council. This strategy includes actions that have been recommended for other priority risk issues (eg. Residential Runoff). The issue focussed primarily upon development of strategies with neighbouring councils to ensure entire waterways are managed, not individual sections.




1 PRI2-SP-01 Stormwater Management Guidelines Refer to PRI1-SP-02

Refer to listed strategies for details regarding cost, responsibility and extent of application.

2 PRI2-SP-02

Catchment Water Quality Management Strategy Water quality management strategies for the waterways entering HBCC would be undertaken to provide a strategic basis for improving water quality in inflows to the waterways throughout their catchments. It would consider the actions of relevant bodies, particularly other Councils upstream, Melbourne Water, EPA and landholders and industries, and would also recommend the role of Council stormwater management plans.

$75,000 $5,000

Melbourne Water, Council

and Neighbouring

Councils

Entire Catchment

3 PRI2-IDC_01 Monitoring and Data Collection Refer to PRI1-IDC-01


4 PRI2-EA-01

Media Release A media release in both local media and the media of neighbouring councils will highlight the impacts that can be experienced downstream from activities undertaken upstream. The key aim of this media release would be would be to inform and educate residents, businesses and industry groups of the impact of their activities on the waterways of Hobsons Bay City Council. Such a media release could be similar to ones undertaken by the EPA showing the impact of local activities (car-washing, etc) on Port Phillip Bay.

$7,500 Council and

Neighbouring Councils

Municipality

5 PRI2-EA-02

Community and Special Interest Groups Community and Special Interest Groups (including “Friends of” Groups) often operate along entire waterways and are not bound by council boundaries. Whilst it is unlikely that HBCC would financially support activities outside the municipality, a joint program could be developed between neighbouring councils and these community or special interest groups.

$15,000 $5,000 Council and Community

Groups Waterways






Risk Management Strategy 3 Priority Risk Issue 3 – Commercial Runoff This strategy has been developed to respond to commercial land use runoff in the entire municipality, which is considered to impact a number of receiving environments. The main focus of the strategy involves the community’s and business owner’s education and awareness, due to the broad scale of the threat. Increasing awareness about stormwater issues can be achieved through stakeholder groups and committees, consultation and guideline development. The strategy also allows for Council to become involved with the business owners by developing site specific EMP’s to improve stormwater performance of individual premises. A number of Water Sensitive Urban Design techniques have been recommended to allow for stormwater treatment without comprising the character of the local region.




1 PRI3-EA-03 Demonstration Projects Refer to PRI1-EA-03


2 PRI3-IDC-01 Monitoring and Data Collection Refer to PRI1-IDC-01, PRI2-IDC-02


3 PRI3-SP-01b Beach Precinct Improvement Strategy Refer to PRI1-SP-01b


4 PRI3-SP-02 Stormwater Management Guidelines Refer to PRI1-SP-02, PRI2-SP-01


5 PRI3-EA-01

Literature/Guideline Development and Distribution Development of literature and guidelines specifically tailored towards commercial premises could be used to educate business owners of their impacts upon the local stormwater system. Requirements upon business owners in terms of stormwater treatment (ie: is an oil grease interceptor required) could be detailed in these guidelines. As with the stormwater management guidelines (PRI1-SP-02), significant cost savings can be achieved through the adaptation of existing resources, guidelines and related materials to make them applicable with the local setting.


6 PRI3-EA-06

Business Stakeholder Groups and Committees Cooperation with the local Traders Association would be encouraged to ensure an approach to stormwater management is consistent across the municipality. This forum also allows for the sharing of knowledge between individual business and Council with regard to stormwater issues or treatments.

$15,000 $2,500 Council and

Business Groups

Local

7 PRI3-WSUD-02

Rainwater Storage and Reuse Rainwater storage and reuse can be encouraged through the use of rainwater tanks. Reuse for toilet flushing and other appropriate uses, reduces the demand on potable water and reduces the runoff from a particular site, thus reducing the contaminants. Whilst Council may choose to install tanks, it is more likely to encourage their use through installation subsides


8 PRI3-WSUD-01

Swales Implement swales where possible and appropriate. Swales can be used instead of conventional kerb and channel drainage. Swales facilitate the removal of pollutants and reduce runoff by encouraging infiltration. Such measures will be highly dependant upon on the available space in and around commercial precincts and potentially may not be feasible in such a location.




9 PRI3-WSUD-03

Stormwater Infiltration Measures Implement stormwater infiltration measures where possible and appropriate. Stormwater infiltration measures can be implemented at the end of swales or open drains. These measures allow for the infiltration of water into the ground and remove pollutants from the stormwater. Stormwater infiltration measures can include either infiltration pits or bio-retention systems. Such measures will be highly dependant upon on the available space in and around commercial precincts and potentially may not be feasible in such a location.


10 PRI3-WSUD-04

Filter Strips Implement filter strips where possible and appropriate. Filter strips are simply strips of vegetation or grass that stormwater flows through in order to drain to the receiving environment. Open drains along the beach may potentially be diverted through a filter strip before entering the bay. Such measures will be highly dependant upon on the available space in and around commercial precincts and potentially may not be feasible in such a location.


11 PRI3-EA-04

Long Term Individual/Organisation Consultation This technique is similar to PRI3-EA-06, however is focussed more on individual consultation as opposed to groups and committees. Aimed at targeting individual businesses that have been determined to be having an impact upon the local stormwater.


12 PRI3-SP-01

Develop and Implement Site Specific EMP's Develop site specific environmental management plans to combat a number of environmental issues including waste disposal, recycling, stormwater runoff and water reuse. These plans could be developed for individual businesses or larger commercial areas (eg: Nelson Place). Through the Victorian Stormwater Action Plan, Melbourne Water, the Land Development Industry and 3 local councils, formulated a site EMP kit. This EMP kit can be adapted to suit the requirements of both Council and differing requirements of each site and will results in cost savings for Council. Such a process would first require a feasibility study to identify the priority sites and a process to address their respective issues.

$20,000 $5,000 Council and EPA Local

13 PRI3-WSUD-05

Gross Pollutant Traps There are still some commercial precincts that do not have adequate trapping for gross pollutants such as litter. A review of areas currently do not receive treatment should be undertaken to ensure trapping through GPTs and side entry pit baskets is implemented where appropriate. Information from existing devices should be reviewed to ensure effective operation.







Risk Management Strategy 4 Priority Risk Issue 4 – Industrial Runoff This strategy responds to the risk of industrial land use runoff within the Hobsons Bay City Council impacting on its receiving environments. The strategy focuses on preventative measures through the development of guidelines, plans and site specific EMP’s to reduce the impact of stormwater on the local environment. Whilst focussing on preventative measures, a number of structural measures, including filter strips and swales have also been recommended.




1 PRI4-EA-03 Demonstration Projects Refer to PRI1-EA-03, PRI3-EA-03


2 PRI4-SP-02 Stormwater Management Guidelines Refer to PRI1-SP-02, PRI2-SP-01, PRI-SP-02


3 PRI4-WSUD-02

Rainwater Storage and Reuse Rainwater storage and reuse can be encouraged through the use of rainwater tanks or stormwater reuse facilities. Reuse for washing, cleaning and other appropriate usesreduces the demand on potable water and reduces the runoff from a particular site, thus reducing the contaminants. Whilst Council may choose to install tanks, it is more likely to encourage their use through installation subsides and incentives. With many warehousing and distribution facilities with large roof areas in the municipality, significant potential exists for the capture and reuse of large quantities of water.


4 PRI4-EA-01

Literature/Guideline Development and Distribution Development of literature and guidelines specifically tailored towards industrial premises could be used to educate industry of their impacts upon the local stormwater system. Requirements upon industry in terms of stormwater treatment (ie: is an trade waste agreement required) could be detailed in these guidelines. As with the stormwater management guidelines (PRI1-SP-02), significant cost savings can be achieved through the adaptation of existing resources, guidelines and related materials to make them applicable with the local setting. Literature could be aimed at both the construction and operational phases of the premises.


5 PRI4-EA-04

Long Term Individual/Organisation Consultation Consultation between individuals/organisations and Council is more likely to achieve positive results for stormwater management as opposed to consultation with groups and committees. Aimed at targeting individual industries that have been determined to be having an impact upon the local stormwater and encouraging all industrial premises to operate within best practice with regard to stormwater management. Use can be made of business newsletters for this action.


6 PRI4-EA-05

Media Release A media release could highlight measure being undertaken by Council to improve stormwater quality and how local industry can help. Any media release could be tied into the HBCC Business Newsletter and thus reduce costs and potentially improve the impact of any message.

$7,500 Council Local

7 PRI4-WSUD-03

Stormwater Infiltration Measures Implement stormwater infiltration measures where possible and appropriate. Stormwater infiltration measures can be implemented at the end of swales or open drains. These measures allow for the infiltration of water into the ground and remove pollutants from the stormwater. Care will need to be taken to ensure liquid contaminants are not allowed




to enter the infiltration measure. Such measures will be highly dependant upon on the available space in and around industrial premises and potentially may not be feasible in such a location.

8 PRI4-WSUD-04

Filter Strips Implement filter strips where possible and appropriate. Filter strips are simply strips of vegetation or grass that stormwater flows through in order to drain to the receiving environment. Filter strips can be as simple as maintained grass or vegetated strip around the boundary of the industrial site. Such measures will be highly dependant upon on the available space in and around industrial premises and potentially may not be feasible in such a location.


9 PRI4-EA-02 Stormwater Management Education Workshops Education sessions for member of industry detailing how the stormwater can impact the local environment and how activities across the municipality can influence stormwater quality.


10 PRI4-EA-06 Signage Development of signage for industry displaying best practice for stormwater management

$10,000 Council Local

11 PRI4-SP-03

Spill Prevention and Containment Plans Spill Prevention and Containment Plans can be used to ensure that any spills that occur on site are contained on site and do not enter the stormwater system. In most cases, spill prevention and containment plans will be included as part of a site Environmental Improvement Plans. However, many smaller light industrial or manufacturing sites (mechanics, spray painters, etc) may not have plans in place to deal with spill prevention and containment and consequently, spills may be entering the local stormwater system.

$25,000 Council and EPA Local

12 PRI4-SP-01

Develop and Implement Site Specific EMP's Environmental Management Plans can be developed for either sections of industry (eg: Slough Estate) or individual sites. EMP’s prescribe environmental management objectives that need to be met for the site can include other factors besides stormwater quality and quantity. Through the Victorian Stormwater Action Plan, Melbourne Water, the Land Development Industry and 3 local councils, formulated a site EMP kit. This EMP kit can be adapted to suit the requirements of both Council and differing requirements of each site and will results in cost savings for Council.


13 PRI4-RE-03 Infringement Notification and Fines Fines and infringement notices to be imposed by either EPA or Council to industrial premises failing to meet licence or discharge requirements and consequently having an adverse impact upon stormwater.


14 PRI4-WSUD-01a

Swales - Kororoit Creek Road Swales can be used instead of conventional kerb and channel drainage. Swales facilitate the removal of pollutants and reduce runoff by encouraging infiltration. Opportunities exist along side Kororoit Creek Road to implement this type of drainage.


15 PRI4-WSUD-01b

Swales - Grieve Parade Swales can be used instead of conventional kerb and channel drainage. Swales facilitate the removal of pollutants and reduce runoff by encouraging infiltration. Opportunities exist along side Grieve Parade to implement this type of drainage.


16 PRI4-RE-02 Audit and Inspection Audit and Inspection of industrial premises to ensure best practice stormwater management is being undertaken and provide opportunities for dialogue between Council, EPA and industry.

$35,000 Council and EPA Local






Risk Management Strategy 5 Priority Risk Issue 5 – Major Road/Rail Runoff The strategy responds to the runoff that occurs from major road/rail infrastructure within the municipality. This strategy focuses predominately with structural treatments to ensure poor quality stormwater does not enter local waterways. However, the strategy also provides for interactions between both Vicroads and Victrack to develop and implement some site specific EMP’s.




1 PRI5-SP-02 Stormwater Management Guidelines Refer to PRI1-SP-02, PRI2-SP-01, PRI-SP-02, PRI4-SP-02


2 PRI5-SP-01

Develop and Implement Site Specific EMP's Environmental Management Plans can be developed for sections of roadway or railway (eg Princes Fwy). Such plans include details of how contaminants are collected and disposed of (tyre shreds, glass, metal, etc), sediment control (from gravel verges) and the collection and treatment of stormwater runoff. Through the Victorian Stormwater Action Program, Melbourne Water, the Land Development Industry and 3 local councils, formulated a site EMP kit. This EMP kit can be adapted to suit the requirements of both Council and differing requirements of each site and will results in cost savings for Council. A process would need to be undertaken to identify and prioritise pollution hotspots along the road and rail network within the municipality.

$10,000 $2,500 Council and VicRoads or

VicTrack

Major Roadways and

Railways

3 PRI5-WSUD-03

Stormwater Infiltration Measures Implement stormwater infiltration measures where possible and appropriate. Stormwater infiltration measures can be implemented at the end of swales or open drains. These measures allow for the infiltration of water into the ground and remove pollutants from the stormwater. Stormwater infiltration measures can include either infiltration pits or bio-retention systems. Application of water sensitive design such as this would be subject to a range of limitations including space constraints, public safety, suitable soil composition and water quality objectives. A feasibility study would be required to assess the opportunities available.


VicTrack

Major Roadways and

Railways

4 PRI5-WSUD-04

Filter Strips Implement filter strips where possible and appropriate. Filter strips are simply strips of vegetation or grass that stormwater flows through in order to drain to the receiving environment. Filter strips can be as simple as maintained grass strip along the roadway prior to runoff entering the drainage system. Application of water sensitive design such as this would be subject to a range of limitations including space constraints, public safety, suitable soil composition and water quality objectives. A feasibility study would be required to assess the opportunities available.


VicTrack

Major Roadways and

Railways

5 PRI5-WSUD-01

Swales Implement swales where possible and appropriate. Swales can be used instead of conventional kerb and channel drainage. Swales facilitate the removal of pollutants and reduce runoff by encouraging infiltration. Application of water sensitive design such as this would be subject to a range of limitations including space constraints, public safety, suitable soil composition and water quality objectives. A feasibility study would be required to assess the opportunities available.


VicTrack

Major Roadways and

Railways






Risk Management Strategy 6 Priority Risk Issue 6 – Boat Ramps

The strategy responds to runoff from the numerous boat ramps and fishing spots along the coast of the City of Hobsons Bay. This strategy recommends no actions that are not previously recommended in previous strategies. This is because all the management actions examined to combat this risk issues were determined to have an inappropriate cost benefit score.




1 PRI6-EA-02 Demonstration Projects Refer to PRI1-EA-03, PRI3-EA-03, PRI4-EA-02


2 PRI6-SP-02 Stormwater Management Guidelines Refer to PRI1-SP-02, PRI2-SP-01, PRI-SP-02, PRI4-SP-02, PRI5-SP-02


3 PRI6-EA-04 Signage Signage can be erected at and around boat ramps and fishing spots advising both boaters and fisherman as to practices that contribute to poor stormwater quality and what they can do themselves to improve the stormwater,

$10,000 Council and

Port of Melbourne

Local

4 PRI6-WSUD-01 Stormwater Infiltration Measures - Car Parks Creating infiltration measures in and around the car parks at boat ramps will prevent pollutants and other contaminants from entering the nearby Port Phillip Bay

$15,000 $2,000 Council and

Port of Melbourne

Local

5 PRI6-WSUD-02 Filter Strips – Between Car Parks and the Foreshore Filter strips will remove pollutants from the runoff from car parks and prevent those contaminants from entering the nearby Port Phillip Bay.

$15,000 $2,000 Council and

Port of Melbourne

Local






Risk Management Strategy 7 Priority Risk Issue 7 – Waterway Degradation

The strategy responds to the priority risk issues of waterway degradation within the municipality. This strategy combines a number of elements from previous strategies. Through the implementation of these strategies, benefits will be seen for this risk issue. An additional action has been added to this strategy however, this action involves the use of infringement notices and fines to combat individuals or companies whose actions result in degradation of the local waterways.




1 PRI7-EA-01 Long Term Individual/Organisation Consultation Refer to PRI1-EA-04, PRI3-EA-04 and PRI4-EA-04


2 PRI7-EA-02 Media Release Refer to PRI1-EA-05, PRI2-EA-01and PRI4-EA-05


3 PRI7-EA-03 Community and Special Interest Group Refer to PRI2-EA-02


4 PRI7-EA-04 Business Stakeholder Groups and Committees Refer to PRI3-EA-06 and PRI4-EA-07


5 PRI7-SC-01 Waterway Rehabilitation and Revegetation Refer to PRI1-SC-01


6 PRI7-SP-01 Develop and Implement Site Specific EMP's Refer to PRI1-SP-01, PRI3-SP-01, PRI4-SP-01 and PRI5-SP-01


7 PRI7-IDC-01 Monitoring and Data Collection Refer to PRI1-IDC-01, PRI2-IDC-01 and PRI3-IDC-01


8 PRI7-RE-01

Infringement Notification and Fines Council could provide infringement notification and fines upon individuals or companies if requirements in either the waterway management strategy or stormwater management guidelines are not met. Individuals could be fined for actions including the riding of trail bikes where prohibited, removal of vegetation, or wilful damage to the environment along the waterway. It is important to distinguish between the responsibilities of Council and those of the EPA. Council has the authority to police local by-laws and impose relevant penalties for non-compliance and it has authority under the Litter Act to impose relevant penalties for non-compliance. The EPA is a statutory body responsible for the enforcing a number of pieces of State legislation, including the Environment Protection Act 1970 and the State Environment Protection Policies (SEPP’s).

$50,000 $10,000 Council and EPA Municipality






Risk Management Strategy 8 Priority Risk Issue 8 – Contaminated Land/Groundwater This strategy has been developed to address to issue of contaminated land and groundwater within the Hobsons Bay City Council. The strategy is aimed predominately at preventing further contamination, whilst educating and raising awareness within the community about existing contamination. Stormwater treatment measures are ineffective at removing contaminants once they have entering the groundwater system. Consequently, the actions proposed to address this priority risk issue are different to those seen for previous priority risk issues. Contaminated Land/Groundwater is potentially located at the site of old industrial premises, landfills and service stations, whilst contaminated groundwater plumes may extend from this sites through underground aquifers to sites away from the initial contamination (including from sites outside the municipal boundary)




1 PRI8-IDC-01 Monitoring and Data Collection Refer to PRI1-IDC-01, PRI2-IDC-01, PRI3-IDC-01 and PRI7-IDC-01


2 PRI8-RE-02

Audit and Inspection Refer to PRI4-RE-02

Aimed at being a preventive measure, but may also be applied to clean up operations.


3 PRI8-RE-03

Infringement Fines and Notification Refer to PRI4-RE-03

Aimed at being a preventative measure


4 PRI8-SP-01

Develop and Implement Site Specific EMP's Refer to PRI4-SP-02



5 PRI8-SP-03

Stormwater Management Guidelines Refer to PRI1-SP-02, PRI2-SP-01, PRI-SP-02, PRI4-SP-02, PRI5-SP-02 and PRI6-SP-02



6 PRI8-SP-04

Spill Prevention and Containment Plans Refer to PRI4-SP-03



7 PRI8-EA-08 Business Stakeholder Groups and Committees This strategy would is similar to PRI8 –EA-02, however would be aimed at provided dialogue and information for business groups and committees as opposed to the general public.


8 PRI8-SP-02

Waste Management Program Development Aimed at being a preventative measure

The development of a waste management program will prevent future contamination of both land and groundwater through the implementation of effective and environmentally sound techniques. This program will also prevent




additional contamination at existing sites.

9 PRI8-EA-04 Long Term Individual/Organisation Consultation Long-term consultation with individuals and/or organisations to identify and manage contaminated sites and ensure measures are put in place to prevent further contamination from occurring.


10 PRI8-EA-01

Literature/Guideline Development and Distribution Literature and/or guideline development would be of benefit in educating the local community and industry about contaminated sites and what they can do about it. Guidelines would help to advise industry on what should be done in order to prevent contamination from occurring. As with the stormwater management guidelines (PRI1-SP-02), significant cost savings can be achieved through the adaptation of existing resources, guidelines and related materials to make them applicable with the local setting.




REACTIVE STRATEGY COST BENEFIT ASSESSMENT G-1


APPENDIX G: REACTIVE STRATEGY COST BENEFIT ASSESSMENT



Table G-1 Strategy Formulation for Stormwater Risk Management Strategy 1

Rank ID Element Types Description/Location

Life

cycl

e

Capital Cost Ongoing Cost Total Cost

% S

ubca

tchm

ents

Effe

ctiv

enes

s

Life

tim

e

Feas

ibili

ty

Mul

tiple

Ben

efit

Des

irabi

lity

Score

1 PRI1-SP-02 Stormwater Management Guidelines 10 $50,000 $5,000 $100,000 100 H 10 H H H 416

2 PRI1-WSUD-02 Rainwater Storage and Reuse 20 $15,000 $5,000 $115,000 40 H 20 H H H 5993 PRI1-EA-01 Literature/Guideline Development and Distribution 5 $20,000 $2,000 $30,000 40 H 5 H H H 625

4 PRI1-WSUD-01 Swales 20 $15,000 $2,000 $55,000 15 H 20 H H H 7645 PRI1-SP-01a Develop and Implement Site Specifc EMP's 10 $20,000 $7,500 $95,000 40 H 25 M M H 776

6 PRI1-SP-01b Beach Precinct Improvement Strategy 10 $10,000 $10,000 5 H 10 H H H 833

7 PRI1-EA-03 Demonstration Projects 25 $100,000 $25,000 $725,000 100 VH 25 H H H 9398 PRI1-EA-04 Long Term Individual/Organisation Consultation 5 $12,000 $5,000 $37,000 40 H 5 M H H 1079

9 PRI1-EA-05 Media Release 1 $7,500 $7,500 40 M 1 H H H 1093

10 PRI1-EA-02 Stormwater Management Education Workshops 1 $7,500 $2,000 $9,500 40 M 1 M H H 1939

11 PRI1-WSUD-04 Filter Strips 20 $15,000 $5,000 $115,000 10 H 20 H H H 2395

12 PRI1-WSUD-03 Stormwater Infiltration Measures 20 $25,000 $5,000 $125,000 10 H 20 H H H 2603

13 PRI1-IDC-01 Monitoring and Data Collection 10 $150,000 $25,000 $400,000 100 M 10 M H H 3265

14 PRI1-SC-01 Waterway Rehabilitation and Revegetation 10 $500,000 $50,000 $1,000,000 75 H 10 M H H 7775

15 PRI1-RE-01 Financial Incentives (eg. Rate Rebates) 1 $10,000 $10,000 40 L 1 VH H H 1890

16 PRI1-WSUD-06a Gross Pollutant Trap - Notla Drain 20 $75,000 $7,500 $225,000 5 M 20 M H H 18367

17 PRI1-WSUD-06b Gross Pollutant Trap - Manning St Drain 20 $75,000 $7,500 $225,000 5 M 20 M H H 18367

18 PRI1-WSUD-06c Gross Pollutant Trap - Civic Pde Drain 20 $75,000 $7,500 $225,000 5 M 20 M H H 18367

19 PRI1-WSUD-06d Gross Pollutant Trap - Millers Rd Drain 20 $75,000 $7,500 $225,000 5 M 20 M H H 18367

20 PRI1-WSUD-06e Gross Pollutant Trap - Paisley St Drain 20 $75,000 $7,500 $225,000 5 M 20 M H H 18367

21 PRI1-WSUD-06f Gross Pollutant Trap - Challis St Drain 20 $75,000 $7,500 $225,000 5 M 20 M H H 18367

22 PRI1-WSUD-05 Existing Wetland Rejuvenation and Rehabilitation 20 $100,000 $15,000 $400,000 5 M 20 M H H 32653

Action Recommended for StrategyAction Not Recommended for StrategyRedundant Actions



Figure G-1 Strategy Formulation for Stormwater Risk Management Strategy 1

Strategy 1 - Cost Effctiveness PlotResidential Runoff Runoff

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1 PRI2-IDC-01 Monitoring and Data Collection Refer to PRI1-IDC-01 $0 0

2 PRI2-SP-01 Stormwater Management Guidelines Refer to PRI1-SP-02 $0 0


4 PRI2-EA-02 Community and Special Interest Groups 10 $15,000 $5,000 $65,000 60 H 10 M M H 884

5 PRI2-SP-02 Catchment Water Quality Management Strategy 10 $75,000 $5,000 $125,000 60 H 10 M M H 1701





Strategy 2 - Cost Effctiveness PlotUpstream Inflows

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1 PRI3-EA-03 Demonstration Projects Refer to PRI1-EA-03 $0 0


3 PRI3-SP-01b Beach Precinct Improvement Strategy Refer to PRI1-SP-01b $0 0


5 PRI3-EA-01 Literature/Guideline Development and Distribution 5 $10,000 $2,500 $22,500 5 H 5 H H H 3748

6 PRI3-EA-06 Business Stakeholder Groups and Committees 5 $15,000 $2,500 $27,500 5 H 5 H H H 4581

7 PRI3-WSUD-02 Rainwater Storage and Reuse 20 $15,000 $1,500 $45,000 2.5 M 20 H H H 5248

8 PRI3-WSUD-01 Swales 20 $15,000 $2,500 $65,000 2.5 H 20 H H H 5414

9 PRI3-WSUD-03 Stormwater Infiltration Measures 20 $15,000 $2,500 $65,000 2.5 H 20 H H H 5414

10 PRI3-WSUD-04 Filter Strips 20 $15,000 $2,500 $65,000 2.5 H 20 H H H 5414

11 PRI3-EA-04 Long Term Individual/Organisation Consultation 5 $12,000 $5,000 $37,000 5 H 5 M H H 8630

12 PRI3-SP-01 Develop and Implement Site Specifc EMP's 25 $20,000 $5,000 $145,000 5 H 25 M M H 9469

14 PRI3-WSUD_05 Gross Pollutant Traps 10 $20,000 $5,000 $145,000 5 L 1 VH H H 10582

15 PRC-RE-01 Financial Incentives (eg. Rate Rebates) 1 $15,000 $15,000 5 H 1 VH H H 9718

16 PRI3-EA-02 Stormwater Management Education Workshops 1 $7,500 $7,500 5 M 1 M H H 12245

17 PRI3-WSUD-05 Drainage Inlet Traps 20 $10,000 $5,000 $110,000 2.5 M 20 H H H 12828

18 PRI3-EA-05 Community and Special Interest Group 5 $15,000 $5,000 $40,000 5 M 5 M H H 13061





Strategy 3 - Cost Effctiveness PlotCommercial Runoff

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1 PRI4-EA-03 Demonstration Projects Refer to PRI1-EA-03 $0 0


3 PRI4-WSUD-02 Rainwater Storage and Reuse 20 $20,000 $2,500 $70,000 30 M 20 H H H 680

4 PRI4-EA-01 Literature/Guideline Development and Distribution 5 $20,000 $2,000 $30,000 30 H 5 H H H 833

5 PRI4-EA-04 Long Term Individual/Organisation Consultation 5 $12,000 $5,000 $37,000 30 H 5 M H H 1438



8 PRI4-WSUD-04 Filter Strips 20 $25,000 $5,000 $125,000 15 H 20 H H H 1735

9 PRI4-EA-02 Stormwater Management Education Workshops 1 $7,500 $2,000 $9,500 30 M 1 M H H 2585

10 PRI4-EA-06 Signage 1 $10,000 $10,000 30 H 1 M M H 2721

11 PRI4-SP-03 Spill Prevention and Containment Plans 1 $25,000 $25,000 30 H 1 H H H 3471

12 PRI4-SP-01 Develop and Implement Site Specific EMP's 25 $70,000 $10,000 $320,000 30 H 25 M M H 3483

13 PRI4-RE-03 Infringement Notification and Fines 10 $75,000 $25,000 $325,000 30 M 10 VH M H 6878

14 PRI4-WSUD-01a Swales - Kororoit Creek Rd 20 $25,000 $5,000 $125,000 5 M 20 H H H 7289

15 PRI4-WSUD-01b Swales - Grieve Pde 20 $25,000 $5,000 $125,000 5 M 20 H H H 7289

16 PRI4-RE-02 Audit and Inspection 1 $35,000 $35,000 30 H 1 M M H 9524

17 PRI4-RE-01 Financial Incentives (eg. Rate Rebates) 1 $25,000 $25,000 30 H 1 H H H 3471

18 PRI4-WSUD-08 Sedimentation Basins - Kayes Drain 20 $60,000 $5,000 $160,000 15 M 20 M L H 10159

19 PRI4-WSUD-05 Screening Devices - Kayes Drain 20 $15,000 $7,500 $165,000 15 L 20 M L H 17460

20 PRI4-WSUD-06 Artificial Wetland - Kayes Drain 20 $100,000 $15,000 $400,000 5 H 20 M H H 23324

21 PRI4-WSUD-07a Gross Pollutant Trap - Slough Estate 20 $75,000 $7,500 $225,000 5 L 20 M L H 71429

22 PRI4-WSUD-07b Gross Pollutant Trap - Burleigh St Drain 20 $75,000 $7,500 $225,000 5 L 20 M L H 71429





Strategy 4 - Cost Effctiveness PlotIndustrial Runoff

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2 PRI5-SP-01 Develop and Implement Site Specific EMP's 25 $10,000 $2,500 $72,500 5 H 25 M M H 4735


4 PRI5-WSUD-04 Filter Strips 20 $25,000 $2,500 $75,000 3 H 20 H M H 7289

5 PRI5-WSUD-01 Swales 20 $20,000 $2,500 $70,000 3 H 20 M M H 9524

6 PRI5-SP-03 Spill Prevention and Containment Plans 1 $10,000 $10,000 5 M 1 M M H 22857

7 PRI5-WSUD-08 Flow Detention Structures (Basins) - Local Scale 20 $75,000 $5,000 $175,000 3 H 20 M M H 23810

8 PRI5-WSUD-02 Porous Pavements 20 $25,000 $2,500 $75,000 3 H 20 L L H 28345

9 PRI5-WSUD-07 Sedimentation Basins 20 $60,000 $5,000 $160,000 3 L 20 M M H 50794

10 PRI5-WSUD-05 Artificial Wetlands (Cnr Princes Fwy & Kororoit Creek Rd 20 $100,000 $15,000 $400,000 3 M 20 M H H 54422

11 PRI5-WSUD-06 Gross Pollutant Traps 20 $75,000 $7,500 $225,000 3 L 20 M M H 71429





Strategy 5 - Cost Effctiveness PlotMajor Road/Rail Runoff

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1 PR6-EA-02 Demonstration Projects Refer to PR11-EA-03 $0 0

2 PR6-SP-02 Stormwater Management Guidelines Refer to PRI1-SP-02 $0 0

3 PR6-EA-04 Signage 10 $10,000 $10,000 1 H 10 M M H 8163

4 PR6-WSUD-01 Stormwater Infiltration Measures - Car Parks 20 $15,000 $2,000 $55,000 1 VH 20 H H H 8908

5 PR6-WSUD-02 Filter Strips - Between Car Park and foreshore 20 $15,000 $2,000 $55,000 1 VH 20 H H H 8908

6 PR6-SP-01 Develop and Implement Site Specific EMP's 10 $15,000 $2,500 $40,000 1 H 10 M H H 23324

7 PR6-EA-01 Literature/Guideline Development and Distribution 5 $5,000 $1,000 $10,000 1 L 5 M M H 38095

8 PR6-EA-03 Media Release 1 $5,000 $5,000 1 M 1 H M H 40816

9 PR6-WSUD-03 Drainage Inlet Traps 20 $7,500 $2,000 $47,500 1 M 20 M L H 45238

10 PR6-EA-06 Business Stakeholder Groups and Committees 5 $10,000 $2,500 $22,500 1 M 5 M M H 51429

11 PR6-EA-05 Community and Special Interest Group 5 $10,000 $2,500 $22,500 1 M 5 L M H 85714





Strategy 6 - Cost Effctiveness PlotBoat Ramps

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1 PRI7-EA-01 Long Term Individual/Organisation Consultation Refer to PRI1-EA-04 $0 0

2 PRI7-EA-02 Media Release Refer to PRI1-EA-05 $0 0

3 PRI7-EA-03 Community and Special Interest Group Refer to PRI3-EA-05 $0 0

4 PRI7-EA-04 Business Stakeholder Groups and Committees Refer to PRI3-EA-06 $0 0

5 PRI7-SC-01 Waterway Rehabilitation and Revegetation Refer to PRI1-SC-01 $0 0

6 PRI7-SP-01 Develop and Implement Site Specific EMP's Refer to PRI1-SP-01 $0 0


8 PRI7-RE-01 Infringement Notification and Fines 10 $50,000 $10,000 $150,000 100 M 10 M H H 680





Strategy 7 - Cost Effctiveness PlotWaterway Degradation

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2 PRI8-RE-02 Audit and Inspection Refer to PRI4-RE-02 $0 0

3 PRI8-RE-03 Infringement Fines and Notification Refer to PRI4-RE-03 $0 0

4 PR9-SP-01 Develop and Implement Site Specific EMP's Refer to PRI1-SP-02 $0 0

5 PR9-SP-03 Stormwater Management Guidelines Refer to PRI1-SP-02 $0 0

6 PR9-SP-04 Spill Prevention and Containment Plans Refer to PRI4-SP-03 $0 0

7 PRI8-EA-08 Business Stakeholder Groups and Committees 5 $15,000 $3,000 $30,000 30 H 5 H H H 833

8 PR9-SP-02 Waste Management Program Development 10 $35,000 $2,500 $60,000 30 H 10 H H H 833

9 PRI8-EA-04 Long Term Individual/Organisation Consultation 10 $12,000 $5,000 $62,000 30 M 10 H H H 1205

10 PRI8-EA-01 Literature/Guideline Development and Distribution 5 $35,000 $2,000 $45,000 30 M 5 M H H 2449




Figure G-8 Strategy Formulation for Stormwater Risk Management Strategy

Strategy 8 - Cost Effctiveness PlotContaminated Land/Groundwater

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hobsons bay city council stormwater management plan volume iii (of 3 volumes…€¦ · ·...

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