Technical Report June 2007 Prepared by Capital Projects Division Department of Sustainability and Environment Water Recycling Options Melbourne Augmentation Program Published by the Victorian Government Department of Sustainability and Environment Melbourne, June 2007 © The State of Victoria Department of Sustainability and Environment 2007 This publication is copyright. No part may be reproduced by any process except in accordance with the provisions of the Copyright Act 1968 . Authorised by the Victorian Government, 8 Nicholson Street, East Melbourne Printed by Classic Colour Copying, Melbourne. Printed on 100% Recycled paper ISBN 978-1-74152-968-5 For more information contact the DSE Customer Service Centre 136 186. Disclaimer This publication may be of assistance to you but the State of Victoria and its employees do not guarantee that the publication is without flaw of any kind or is wholly appropriate for your particular purposes and therefore disclaims all liability for any error, loss or other consequence which may arise from you relying on any information in this publication. Water Recycling Options 1.0 Context...........................................................................................1 2.0 Eastern Treatment Plant Upgrade...............................................2 2.1 Summary ..............................................................................2 2.2 Project overview ...................................................................2 Table contents of 2.2.1 Upgrade proposal and timelines..................................... 4 2.3 Opportunities for recycling of treated ETP water..................5 2.3.1 Volume of recycled water available from ETP................ 5 2.3.2 Classes of recycled water............................................... 6 2.3.3 Strategy for identifying recycling uses............................ 7 3.0 Eastern Water Recycling Proposal (EWRP) ...............................9 3.1 Summary ..............................................................................9 3.2 Project overview ...................................................................9 3.3 Project components ............................................................10 3.3.1 Recycled Water Scheme.............................................. 10 3.3.2 Released Water Scheme.............................................. 13 3.3.3 Recycled Water Health and Environmental Requirements............................................................................... 15 3.3.4 EWRP under the 100-year inflow scenario .................. 15 3.3.5 EWRP under reduced inflow scenarios........................ 16 3.3.6 Timelines ...................................................................... 17 3.4 Potential benefits of the EWRP proposal ...........................17 3.4.1 Securing water for cities, towns and industry for the future 17 3.4.2 Water for rivers ............................................................. 18 3.4.3 Improving the health of Lake Wellington ...................... 18 3.4.4 Significant reductions in ocean outfall discharges........ 18 3.4.5 Closure of the Gippsland Regional Outfall Sewer........ 19 3.4.6 Increased economic development in the Gippsland Region 19 3.5 Key issues for further investigation.....................................19 3.5.1 Industry requirements and agreements........................ 19 3.5.2 Water availability in an altered climate ......................... 20 3.5.3 Technical specifications................................................ 21 3.5.4 Environmental, social and economic issues................. 21 3.5.5 Procurement options .................................................... 22 4.0 Substitution of environmental flows: Yarra River ...................23 4.1 Summary ............................................................................23 4.2 Project overview .................................................................23 4.3 Project components ............................................................24 Water Recycling Options Table of contents (continued) 4.3.1 Further advanced treatment at ETP ............................. 24 4.3.2 Transfer infrastructure from ETP to Yarra River........... 26 4.3.3 Winneke Water Treatment Plant requirements ............ 27 4.3.4 Overall scheme............................................................. 28 4.3.5 Scheme capacity and potential additional water supply yield 29 4.3.6 Operational regimes ..................................................... 29 4.4 Project costs and timelines.................................................30 4.4.1 Estimated scheme costs............................................... 30 4.4.2 Capital costs ................................................................. 30 4.4.3 Operating costs ............................................................ 31 4.4.4 Preliminary estimated project timelines........................ 31 4.4.5 Contribution to water supply for Melbourne.................. 31 4.5 Environmental and social issues ........................................31 4.5.1 Pipeline route................................................................ 31 4.5.2 River discharge location ............................................... 32 4.5.3 Receiving water quality implications............................. 32 4.5.4 Environmental flow implications ................................... 35 4.5.5 Implications for the marine environment at Boags Rocks 36 4.5.6 Community concerns.................................................... 36 4.5.7 Public health ................................................................. 36 4.6 Key issues for further investigation.....................................37 5.0 Other options...............................................................................39 5.1 Increased commercial reuse of recycled water ..................39 5.2 Indirect potable reuse .........................................................39 6.0 Appendices..................................................................................41 Appendix 1: Pipeline route report: ETP to the Yarra River Appendix 2: Preliminary assessment of waterway health issues arising from the ‘ETP to Yarra’ water supply augmentation proposal Water Recycling Options 1.0 Context In response to the extended drought and potential for climate change to cause reduced inflows to water supply catchments, the Government has investigated options to deliver significant augmentations to Melbourne’s potable water supply. A new desalination plant will be constructed, and modernisation of irrigation systems in northern Victoria will provide for the transfer of water by pipe to Sugarloaf Reservoir. The Government has also committed to investigating a broad range of options for the use of recycled water, including from the Eastern Treatment Plant (ETP). This report sets out the proposal to upgrade the ETP, and summarises past and recent investigations into two significant opportunities to use high quality treated water from the ETP in order to free up additional potable supply to Melbourne: • the Eastern Water Recycling Proposal (EWRP), which would see recycled water sent to the Latrobe Valley for use by industry, substituting their current regional water supplies and releasing a proportion of these supplies for augmentation of Melbourne’s supply • adding recycled water to environmental flows in the Yarra River below Yering Gorge, allowing additional water to be harvested from the Yarra River into Sugarloaf Reservoir for conventional treatment for potable supply (the ‘ETP to Yarra’ option). Melbourne Water will upgrade the Eastern Treatment Plant (ETP) by 2012 to a full- scale tertiary treatment facility. The ETP tertiary treatment facility will be capable of treating up to 780 million litres of wastewater per day, ensuring that the ETP can treat all normal and wet weather flows to a Class A recycled water standard. This facility will be the largest of its type in Australia, and one of the largest in the world. Class A recycled water is suitable and safe for a wide range of agricultural, industrial and non-potable domestic uses. With further treatment, the water would be suitable for an even wider range of uses, including further industrial, commercial and domestic uses and substitution of environmental flows. Providing recycled water to these uses would free up the potable water they currently take from the reticulated supply system. The recent investigations into the EWRP and ETP to Yarra option have included: • design (or update) of the system components required for each of the options to deliver the maximum amount of potable water to augment Melbourne’s water supply • evaluation of the options under different climate/inflow scenarios set out in the Victorian Water Plan • costing of the options in different climate/inflow scenarios • desktop review (or update) of the environmental, social and economic issues associated with each option • identification of the issues that would need to be addressed in any further business case evaluation on the options. This report firstly summarises the proposal to upgrade the ETP, then describes and evaluates the EWRP and ETP to Yarra options. Appendices contain more details on the proposals, including a technical report on the environmental health issues associated with substitution of environmental flows in the Yarra River. Water Recycling Options 2.0 Eastern Treatment Plant Upgrade 2.1 Summary The Eastern Treatment Plant (ETP) will be upgraded by 2012 to tertiary standard,