New Munster Pump Station and Bibra Lake Main Sewer Extension Environmental Review FINAL REPORT December 1998 628.2(941 .2) GUT 111111111111111111111111111111111111111111111111 Copy A 981043/1 WAT E R Department of Environmental Protection Library CORPORATION LIBRARY DEPARTMENT OF ENVR0NMENTAL PROTECTION Invitation to make a submission WEThALIA SQUARE 141 Si GEORGES TERRACE, PERTH The Environmental Protection Authority (EPA) invites people to make a submission on this proposal. The Water Corporation proposes to expand its sewage pumping capacity at Munster by constructing another pump station (No.3) and the extension of the Bibra Lake main sewer. In accordance with the Environmental Protection Act, a PER has been prepared which describes this proposal and its likely effects on the environment. The PER is available for a public review period of 8 weeks from 4th January 1999 closing on 1st March 1999. Comments from government agencies and from the public will help the EPA to prepare an assessment report in which it will make recommendations to government. Why write a submission? A submission is a way to provide information, express your opinion and put forward your suggested course of action - including any alternative approach. It is useful if you indicate any suggestions you have to improve the proposal. All submissions received by the EPA will be acknowledged. Submissions will be treated as public documents unless provided and received in confidence subject to the requirements of the Freedom of Information Act, and may be quoted in full or in part in the EPA's report. Why not join a group? If you prefer not to write your own comments, it may be worthwhile joining with a group interested in making a submission on similar issues. Joint submissions may help to reduce the workload for an individual or group, as well as increase the pool of ideas and information. If you form a small group (up to 10 people) please indicate all the names of the participants. If your group is larger, please indicate how many people your submission represents. Developing a submission You may agree or disagree with, or comment on, the general issues discussed in the [PER] or the specific proposals. It helps if you give reasons for your conclusions, supported by relevant data. You may make an important contribution by suggesting ways to make the proposal more environmentally acceptable. When making comments on specific elements of the PER: clearly state your point of view; indicate the source of your information or argument if this is applicable; and suggest recommendations, safeguards or alternatives. N:\61 1\600939\WP\32218.doc Points to keep in mind By keeping the following points in mind, you will make it easier for your submission to be analysed: attempt to list points so that issues raised are clear; a summary of your submission is helpful; refer each point to the appropriate section, chapter or recommendation in the PER; if you discuss different sections of the PER, keep them distinct and separate, so there is no confusion as to which section you are considering; attach any factual information you may wish to provide and give details of the source; and make sure your information is accurate. Remember to include: your name; address; date; and whether you want your submission to be confidential. The closing date for submissions is : 1St March 1999 Submissions should be addressed to: The Environmental Protection Authority Westralia Square 141 St George's Terrace PERTH WA 6000 Attention : Wes Horwood N:\61 1 \600939\WP\322 1 8.doc New Munster Pump Station and Public Environmental Review Bibra Lake Main Sewer Extension FINAL 22/12/98 Gutteridge Haskins & Davey Pty Ltd ACN 008 488 373 GHD House 239 Adelaide Tce Perth WA 6004 P0 Box Y3106 Perth WA 6832 Australia Telephone:61 8 9429 6666 Facsimile: 61 8 9429 6555 © Gutteridge Haskins & Davey Pty Ltd 1998 This document is and shall remain the property of Gutteridge Haskins & Davey Pty Ltd. The document may only be used for the purposes for which it was commissioned and in accordance with the Terms of Engagement for the commission. Unauthorised use of this document in any form whatsoever is prohibited. Rev Author Reviewer Approved for Issue No. Name Signature Date U M Goldstone D Boland D Boland 01\12\98 1 M Goldstone D Boland D Boland 08\12\98 2 M Goldstone D Boland 3 M Goldstone D BoIe' Document Number; 10195 New' Job Number; 611/600939/00 New Munster Pump Station and Public Environmental Review Bibra Lake Main Sewer Extension FINAL 22/12/98 Contents Executive Summary ...................................................................I Background and Proposal Justification ...................................6 2.1 The Need for Ocean Disposal . ............................................................... 6 2.2 The need for large Wastewater Treatment Plants ................................8 2.3 The need for additional wastewater pumping capacity at Munster.. 10 Options for extending the Perth South Reticulation Sewerage System. ......................................................................................... 13 3.1 Alignments Avoiding the System 6 Areas .......................................... 13 3.2 Additional Pumping capacity on Mayor Road with Pressure Main across the Wetland..................................................................................... 13 3.3 Aligning the Extension to the Main Sewer along the Proposed Beeliar DriveExtension........................................................................................... 14 3.4 Options Leading to a Wetland Crossing North of Lake Coogee ....... 14 3.5 Selection of the Preferred Option........................................................ 19 3.5. lEn gineering Risk Assessment Workshop......................................... 19 3.5.2 Community Meetings....................................................................... 19 3.6Community Feedback............................................................................ 19 3.7 Environmental Risk Assessment Workshop ...................................... 20 3.8 The Preferred Option............................................................................ 20 3.8.1 Sewer alignment.............................................................................. 20 3.8.2 Pump Station Layout....................................................................... 23 3.8.3 Overflow from the Pump Station...................................................... 25 3.8.4 Enclosed Storage............................................................................ 25 3.8.5 Open Storage.................................................................................. 26 3.8.6 Emergency Overflow ....................................................................... 26 EPA Guidelines ........................................................................28 Existing Environment ...............................................................32 5.1 Physico-chemical Environment...........................................................32 5.1.1 Meteorology .............................................. ..................................... 32 5.1.2 Topography.....................................................................................32 5.1.3 Geology ........................................................................................... 33 5.1.4 Groundwater Flow Systems ............................................................. 35 5.1.5 Salt Water/Fresh Water Interface....................................................37 5.1.6 Regional and Local Water Quality...................................................37 5.1.7 Groundwater/Surface Water Interactions.........................................39 Document Number. 10195 New Munster Pump Station and Bibra Lake Main Sewer Extension Job Number: 611/600939/00 Public Environmental Review New Munster Pump Station and Public Environmental Review Bibra Lake Main Sewer Extension FINAL 22/12/98 5.1.8 Chemical Analyses.......................................................................... 39 5.1.9 Chemical Analysis Results.............................................................. 40 5.2 Contaminated Site Assessment........................................................... 43 5.3 Biological Environment........................................................................ 48 5.3.1 Vegetation........................................................................................ 48 5.3.2 Floristic Survey................................................................................ 51 5.3.3 Flora................................................................................................ 52 5.3.4 Bush/and Condition ......................................................................... 54 5.3.5 Fauna and Habitats ......................................................................... 56 5.3.6 Lake Coogee................................................................................... 58 5.4 Hydrological Connectivity.................................................................... 61 Natural Heritage .......................................................................64 6.1Statement of Significance ....................................................................64 6.2 Description of Beeliar wetlands...........................................................65 6.3 Western chain areas .............................................................................. 65 6.4 Condition and Integrity.........................................................................66