Technical Report June 2007 Prepared by Capital Projects Division Department of Sustainability and Environment Water Recycling Options Augmentation Program

Published by the Victorian Government Department of Sustainability and Environment Melbourne, June 2007

© The State of 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 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 Wellington ...... 18 3.4.4 Significant reductions in ocean outfall discharges...... 18 3.4.5 Closure of the 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: ...... 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 .

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 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 , 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, at a cost of approximately $300 million, including construction of a tertiary filtration plant and enhanced disinfection to achieve Class A standard for ETP recycled water (currently Class C standard). Class A recycled water is suitable for a wide range of uses. The plant’s output is dependent on input flows, but will be over 100 GL/year.

Technology trials will be conducted over the next two years to evaluate options for tertiary treatment to Class A standard and additional treatment to improve colour and odour of the effluent discharged at Boags Rocks.

Further investigations will be conducted over the next 12 months into options for the increased reuse of recycled water from the ETP, including clarifying implications for the volume and quality of effluent that would still be discharged via the Boags Rocks outfall if reuse schemes were introduced.

The results of these technology trials and investigations will inform a decision by 2009 on whether to extend the Boags Rocks ocean outfall.

2.2 Project overview The Eastern Treatment Plant (ETP), at Bangholme in Melbourne’s south east, treats about 350 million litres per day (over 40%) of Melbourne’s sewage. It uses mechanical and biological processes to treat sewage to a secondary standard prior to disinfection. A portion is recycled within the plant and by external users, with the remainder of the treated effluent discharged under an EPA Victoria licence via a 56 kilometre pipeline, the South East Outfall (SEO), into Bass Strait at a shoreline discharge point at Boags Rocks, on the southern Mornington Peninsula.

In 1995, EPA Victoria issued a revised discharge licence for the ETP that required to meet improved environmental standards, including studies to: • examine initiatives to increase water recycling from the plant that would facilitate improved environmental performance at the discharge point • examine dispersion and environmental impacts for a range of outfall extension initiatives.

Melbourne Water was also required to undertake and implement a community consultation process on proposals to upgrade the ETP.

In late 1996, Melbourne Water engaged CSIRO to assess the environmental impact of the effluent discharge on the marine environment at Boags Rocks and to determine the best way of reducing the impact. An essential component of the study process was to involve the community and this was done through the establishment of several community reference groups, which included representatives of environment groups, surf riders, the local community and government agencies. The community supported the final report when it was published by CSIRO in June 1999.

The study found that there was a need to reduce ammonia and nutrient loads in the effluent discharge and to increase recycling of effluent, while also reducing inflows to

Water Recycling Options

the plant. The study also found that extending the outfall would greatly reduce existing shoreline impacts on marine life, and minimise impacts offshore from an appropriately extended outfall with diffuser s, but that this would not reduce nutrient loads. The study found that there was also a need to build on existing knowledge through continued monitoring and research.

In December 2001, Melbourne Water developed a Plan for Sustainable Resource Management at ETP as part of a works approval application to EPA Victoria. This plan included the following key components: • works to reduce ammonia concentration in the treated effluent to reduce the toxicity of the effluent and nutrient loads thereby improving the environment for marine life • upgrade works to implement tertiary filtration and enhanced disinfection to facilitate recycling of treated effluent and consequently reduce the amount of effluent discharged to the ocean. These upgrade works would also mitigate aesthetic issues and perceived public health issues at the discharge point.

After further consultation with stakeholders, EPA Victoria issued a works approval for the proposed upgrade works in July 2002. The key conditions in the works approval were: • construction of a tertiary filtration and enhanced disinfection upgrade to achieve Class A quality for recycled water • extension of the effluent ocean outfall at Boags Rocks to establish a new discharge point at least two kilometres off-shore.

Following consideration by the Victorian Civil and Administrative Tribunal of a number of appeals against the works approval, it was reissued with similar conditions in November 2003.

Melbourne Water then commenced implementation of the ammonia reduction upgrade and is proceeding towards staged completion of construction works between late 2007 and 2010.

By agreement with EPA, implementation of the tertiary treatment upgrade and of works to extend the ocean outfall were deferred for two years pending the outcomes of a range of scientific investigations including an assessment of the expected effects of the tertiary treatment upgrade works and any reduction in outflow resulting from recycling initiatives, in particular from the Eastern Water Recycling Proposal. Melbourne Water submitted a report on the outcomes of these studies in September 2006 and a further report in November 2006 outlining a proposed program of actions in response to these investigations.

Water Recycling Options

Figure 1: Major sewerage treatment plants and pipes.

2.2.1 Upgrade proposal and timelines The current proposal involves proceeding with a staged upgrade of ETP to a tertiary treatment facility designed to treat up to 780 million litres per day, ensuring that the ETP can treat all wet weather flows to a Class A standard. This facility will be the largest of its type in Australia, and one of the largest in the world.

The planned or proposed works include: • Works to reduce ammonia in the treated effluent are continuing with Stage 1 to be delivered in 2007 and Stage 2 in 2010. • Upgrade the effluent quality discharged to Bass Strait using tertiary filtration and ultra violet disinfection, aimed at completion by November 2012. • Conduct investigations and complex technology trials in 2008 on options for tertiary treatment to achieve Class A standard recycled water, and advanced treatment to reduce colour and odour effects at the shoreline discharge point. • The results of the trials will inform a decision in 2009 on whether or not this additional advanced treatment technology will be implemented as part of the upgrade works, and how efficiencies could be achieved by integrating the advanced treatments with the other proposed upgrades. • Monitor progress on achieving major recycling opportunities and confirm in 2009 a proposed direction to either implement additional advanced effluent treatment and retain a shoreline discharge at Boags Rocks (in anticipation of major recycling), or alternatively to extend the existing ocean outfall.

Water Recycling Options

Figure 2: An aerial photograph of the current ETP

2.3 Opportunities for recycling of treated ETP water

2.3.1 Volume of recycled water available from ETP The ETP treats an average of 370 million litres of wastewater per day.

In wet weather, the sewerage system carries much more water, but with less concentrated contaminants. Under wet weather inflow conditions, the upgraded ETP will produce up to 700 million litres per day of water meeting Class A standards.

The amount of water flowing in the sewerage system (and therefore potentially available for recycling) is also dependent on the amount of water being sent to sewer after use in households, business and industry, parks and gardens and by other users.

During water restrictions, less water typically flows in the system. Similarly, water conservation programs in households and industry can be expected to reduce water flowing in the system over time.

Against this, population growth will lead to an increase in the number of households and businesses using water. The establishment of new water supplies such as desalination plants or a return to higher rainfall patterns would reduce the time spent on water restrictions, potentially leading to increased flows in the sewerage system.

The ETP upgrade is expected to provide (allowing for existing commitments to supply recycled water):

Water Recycling Options

• at least 110 GL of Class A water per year at an annual average daily flow rate of about 305 million litres (under continued drought conditions and Stage 3 water restrictions) • up to 130 GL of Class A water per year at an annual average daily flow rate of about 350 million litres after the return to normal water security and supply targets (ie. after Stage 3 restrictions are lifted) • taking into account the plant’s capacity to treat wet weather inflow peaks to produce up to 700 million litres of Class A water per day, the total volume of Class A water produced by ETP could be in the order of around 145 GL in a wet year.

2.3.2 Classes of recycled water Recycled water can be safely used for a variety of purposes that are appropriate to the level of treatment it has undergone. EPA Victoria administers current Acts, policies and regulations relevant to recycled water. EPA Victoria's Guidelines for Environmental Management: Use of Reclaimed Water (August 2002) gives the framework for best practice management for the production and use of recycled water.

Recycled water is typically used for crops such as tree plantations, vineyards, general agriculture and irrigation of golf courses and parklands under controlled conditions. With an appropriate level of treatment and preventative management controls, recycled water can also be used on vegetable crops that are eaten raw and dual pipe residential supply systems for toilet flushing and garden watering.

Presently, Victorian EPA guidelines specify four classes of recycled water, which are summarised as follows:

Class A This is the highest quality of recycled water. A tertiary treatment process combined with high levels of pathogen reduction is required to produce water of this quality. It is not suitable as .

Class A recycled water has the widest range of uses, including: • residential garden watering • closed system toilet flushing • process/cooling water for industry • fire protection stores and reticulation systems • irrigation of municipal parks and sportsgrounds • water for contained or ornamental ponds • food crops that are consumed raw or sold to consumers uncooked or processed • all of the uses listed for classes B, C and D.

Class B A secondary treatment process, combined with some pathogen reduction is used to produce water of this quality.

Class B recycled water with appropriate management practices may be used for the following purposes: • irrigation of dairy cattle grazing fodder

Water Recycling Options

• livestock drinking water (not including pigs) • wash down water for dairy sheds and stockyards (not including milking equipment) • urban (non-potable) uses with restricted public access • closed industrial systems • all of the uses listed for classes C and D.

Class C A secondary treatment process combined with minor pathogen reduction is used to produce water of this quality. The ETP currently produces Class C recycled water .

Class C recycled water with appropriate management practices may be used for the following: • cooked/processed human food crops • selected (raw/unprocessed) crops not directly exposed to recycled water (eg. apples) • grazing/fodder for cattle, sheep, horses, goats etc. • grazing for dairy cattle (subject to a five day withholding period after irrigation) • urban (non-potable) uses with restricted public access • closed industrial systems • all of the uses listed for Class D.

Class D A secondary treatment process with little or no pathogen reduction is used to produce water of this quality.

Class D recycled water can only be practically used for production of non-food crops such as woodlots, turf growing and flowers.

2.3.3 Strategy for identifying recycling uses The Government’s commitment to upgrade the ETP was made in the context of the Central Region Sustainable Water Resources Strategy (CRSWS), which proposes a program of actions, including increased recycling of treated effluent to address the potential for shortage of fresh water resources in Victoria. The strategy emphasised the potential environmental, social and economic benefits associated with water recycling to achieve water savings for potable use and environmental flows.

Potential future large-scale uses for recycled water from ETP following the completion of the upgrade works program could include schemes such as the EWRP or ETP to Yarra option, or other smaller, local recycling uses.

Each of these options would require additional treatment beyond Class A standard to meet the requirements of industrial users or relevant environmental and public health standards.

The additional treatments required for the recycling uses may have implications for the new treatments currently proposed as part of the ETP upgrade. Opportunities may exist to coordinate the technology upgrades, and any significant reuse or

Water Recycling Options

diversion of water from the ETP may reduce the need for significant upgrade of the Boags Rocks outfall.

Any further investigation of any option for use of recycled Class A water from the ETP will need to address the interrelationships between the recycling proposal, the ETP and effects on any existing users of recycled water.

Water Recycling Options

3.0 Eastern Water Recycling Proposal (EWRP)

3.1 Summary The EWRP has two components: • a Recycled Water Scheme sending treated ETP water to the Latrobe Valley for use by industry and increasing environmental flows in the • a Release Scheme returning freed-up water for potable use in Melbourne.

Variants of the EWRP have been designed and costed on the basis of different water availability and demands ranging between the 100-year and 10-year inflow scenarios. Further work is required to develop schemes for other climate scenarios.

EWRP component Capex Opex Annual volume of water $ billion $ billion delivered (GL) (NPC) (NPC)

Recycled Scheme 1.4 - 2.0 0.5 - 0.7 80 - 115

Release Scheme 0.5 - 0.7 0.1 - 0.2 60 - 90

The EWRP could be constructed and operational soon after the ETP upgrade.

3.2 Project overview The Latrobe Valley has a concentration of a small number of relatively big water users: the Yallourn W, Loy Yang A and B, Hazelwood and Morwell power stations, and the Australian Paper Maryvale pulp mill.

Although they are more than 100 kilometres from Melbourne, the potential to supply recycled water to these users is a relatively simple and cost-effective option compared with the distribution of water to many industrial users closer to Melbourne.

Collectively, these industrial plants use approximately 117 GL of water per year, or about 25% of Melbourne’s annual potable use. Most of this water is drawn from the Latrobe River, Blue Rock and Moondarra Reservoir. Much is lost to evaporation in cooling processes in the power plants, or is too contaminated by the industrial processes to be reused or returned to the river system.

The EWRP could provide fit-for-purpose recycled water from the ETP to these industries, thereby freeing up the river and dam water that they would otherwise use. The project includes additional treatment in the Latrobe Valley so that the water could meet the specific needs of each plant and could be cycled through some processes several times.

Some of the freed-up water would be piped to Melbourne for addition to potable supplies. The project would create additional environmental flows for the Latrobe River, by allowing some of industry’s bulk entitlements to be released for environmental flows.

Water Recycling Options

The EWRP has undergone a significant amount of design development and feasibility evaluation, including: • technical reviews of treatments required to make water fit-for-purpose for the intended uses • several phases of evaluating options for system configuration, scale and locations • assessments of the potential demand in the Latrobe Valley and the potential volumes of water that would be freed-up under different climate change and water use scenarios • costing of the preferred and alternative schemes.

The Eastern Water Recycling Proposal Feasibility Outcomes Report (October 2006) (EWRP Feasibility Outcomes report) summarised more than two years of detailed investigation into the EWRP. The key elements and findings of the EWRP Feasibility Outcomes report are still relevant to an understanding of the EWRP, including its technical specifications and assessment of potential environmental, social and economic benefits and key issues that would require resolution for the project to proceed.

This Technical Report presents an update of the findings of previous feasibility assessment, in particular: • revised design and costs of the original EWRP project under different supply and demand and inflow scenarios • bringing the costs in line with methods used to evaluate other potential major augmentation options for Melbourne’s water supply • updating costs to reflect current industry experience in the supply and construction of pipes and treatment plants.

3.3 Project components The EWRP has been developed as two key components: • a Recycled Water Scheme sending treated ETP water to the Latrobe Valley for use by industry and augmentation of environmental flows in the Latrobe River • a Release Scheme returning freed-up water for potable use in Melbourne.

3.3.1 Recycled Water Scheme Overview The Recycled Water Scheme, based on the 100-year inflow scenario, consists of: • a 130 kilometre pipeline to deliver up to 115 GL/year of Class A ultra-filtered and chlorinated recycled water from the ETP to the Latrobe Valley for use in the cooling towers at the Yallourn, Loy Yang A and B and Energy Brix power stations • three reverse osmosis post treatment plants treating the cooling tower waste water from these plants prior to discharge to the Latrobe River system and re- use by Hazelwood Power Station and Australian Paper • one of the post treatment plants will be an extension of the Gippsland Water Factory reverse osmosis treatment plant which will provide an additional 7.3 GL/year of recycled water for use by Australian Paper

Water Recycling Options

• a new or augmented pipe and storage system in the Latrobe Valley to provide for the efficient transfer of treated water between the industrial users • augmentation of the existing Saline Waste Ocean Outfall (SWOP) at McGaurans Beach to dispose of treated industrial waste water • closure of the Regional Outfall Sewer.

The scheme is shown in Figures 3 and 4.

Water Recycling Options

Transfer System – Eastern Treatment Plant to Latrobe Valley The transfer main from the ETP at Carrum to the Latrobe Valley has been located on an alignment south of the Princes Highway, which generally passes through rural areas east of Melbourne.

The route generally avoids built-up areas, except after the township of Trafalgar, where it follows the freeway through Moe to the Latrobe Valley.

The scheme incorporates two transfer pump stations. The first is to be located at the ETP and the second near Drouin (approximately half way).

Latrobe Valley Infrastructure Pipelines The scheme incorporates: • pipelines from the reverse osmosis treatment plants located at Yallourn, Loy Yang and the Gippsland Water Factory, to provide recycled water to Australian Paper and Hazelwood Power Station • pipelines from the reverse osmosis treatment plants to maintain water flows to the , Traralgon Creek and Bennett’s Creek • waste pipelines from the three reverse osmosis treatment plants to the saline water holding basin at • a duplicate SWOP between the saline water holding basin at Loy Yang Power Station and the marine outfall at McGaurans Beach.

Pump Stations The scheme incorporates eight distribution pump stations located in the Latrobe Valley. Five are required to dispose of salty waste from the reverse osmosis treatment plants. Three pump stations are also required to deliver water to maintain discharges from industry to rivers and creeks, and to provide recycled water from the reverse osmosis treatment plants to Australian Paper and Hazelwood Power Station.

Treatment Plants The following post-treatment plant works are required in the Latrobe Valley: • The treatment plants in the Latrobe Valley are based on conventional reverse osmosis technology and will produce an effluent quality that is suitable for discharge to river systems and for recycling to Hazelwood Power Station and Australian Paper. The Gippsland Water Factory augmentation includes further treatment of the effluent to remove colour prior to reverse osmosis treatment. • Three post-treatment plants were determined to be more cost effective than a single large centralised plant. This is mainly because the decentralised option reduces capital and operating costs associated with infrastructure required to collect waste streams from industry and distribute treated water.

Storages Recycled water storages are required to: • provide a buffer to cater for daily flow variations from both supply and demand systems • provide balancing storage to overcome any demand shortfall during exceptionally dry years

Water Recycling Options

• provide emergency storage for short term supply interruptions • provide the necessary supply buffer for change over to river supply, should this be necessary, to cater for longer term water supply interruptions.

Waste Discharge Allowance has been made for the augmentation of the existing saline waste outfall pipeline to cater for discharges of salty waste from the new post-treatment plants. The existing outfall is currently licensed for saline wastes only and not for the discharge of residual wastewater effluent from the reverse osmosis treatment plants. Consequently it is envisaged that a new EPA discharge licence will be required for this discharge.

3.3.2 Released Water Scheme

Overview The Released Water Scheme, based on the 100-year inflow scenario, consists of: • a 15 kilometre pipeline from Moondarra Reservoir to , and a 90 kilometre pipeline from Blue Rock Dam to transfer up to 92 GL/year of water to • a new water treatment plant to treat the transferred water to conform with Australian Drinking Water Quality guidelines.

The scheme allocates 9 GL/year of water to Gippsland Water to meet future urban needs in Gippsland (as defined by the CRSWS), and provides up to an additional 38 GL/year for increased environmental flows to the Latrobe River and Gippsland .

The availability of water to the release scheme is dependent on the release or acquisition of the current bulk entitlements and water rights to water held by the industrial users, and on the level of inflows into the Blue Rock and Moondarra storages.

The scheme is shown diagrammatically overleaf.

Water Recycling Options

Figure 5: The Released Water Scheme.

Scheme components The scheme comprises: • a pump station at Moondarra Reservoir and transfer pipeline to Blue Rock Lake • a pump station at Blue Rock Lake and transfer pipeline to Rokeby South • a water treatment plant at Rokeby South • a pump station at Rokeby South water treatment plant and transfer pipeline to Cardinia Reservoir • a re-chlorination facility near Cardinia.

The Moondarra Reservoir pump station will be located near the foot of the dam wall and the outlet pipe. The preferred pipeline route from the Moondarra Reservoir incorporates the existing Gippsland Water pipeline easement that extends from Blue Rock Lake outlet to Moondarra Reservoir catchment. A new connecting pipeline and easement acquisition from the Moondarra Reservoir outlet to the Blue Rock- Moondarra pipeline easement will be required.

The Blue Rock Lake pump station will be located near the foot of the dam wall and the outlet pipe. The proposed alignment follows the existing access road from the Blue Rock Lake outlet, then along private land and minor roads until it reaches the Longford-Dandenong gas pipeline easement, approximately ten kilometres north west of Moe. The proposed alignment generally runs parallel to the gas pipeline easement and other major service easements to the north of Beaconsfield, where it follows the Cardinia-Pearcedale water supply pipeline route to the Cardinia Reservoir outlet works. Local deviations from this alignment will be necessary to avoid current and planned residential zoned land, to connect to the proposed water treatment plant south of Rokeby and to avoid urban development limits in some towns.

This is the shortest feasible route and is expected to cause the minimum social disruption of any route considered. The route is generally through rural zoned or

Water Recycling Options

improved farm land; hence planning or environmental constraints are not expected to prevent use of this route.

The Released Water Scheme water treatment plant will be located on a suitable site in the area south of Rokeby. Consideration would be given to an option to collocate or with or augment the proposed new Melbourne Water Tarago water treatment plant. The water treatment plant site will include the Rokeby South to Cardinia Transfer Pump Station required to supply treated water directly into the Melbourne Water’s distribution system downstream of Cardinia Reservoir.

3.3.3 Recycled Water Health and Environmental Requirements A study was undertaken to: • identify inherent human health and environmental risks associated with the use of recycled water within each intended customer’s operations • establish risk-based controls on the design and operation of recycled water treatment and delivery systems that ensure compliance with the Draft National Guidelines for Water Recycling - Managing Health and Environmental Risk (NRMMC, 2005) • develop a recycled water quality specification to mitigate those inherent risks remaining after the application of management controls.

The study involved a detailed risk assessment of the inherent human health and environmental risks associated with each intended customer’s operations. This was based on supplying Loy Yang A and B, Yallourn Energy and Energy Brix with recycled water following tertiary treatment, and International Power Hazelwood and Australian Paper with reverse osmosis treated water.

In developing the tertiary treatment stage, it was acknowledged that the tertiary treatment technology finally adopted could include a range of technologies depending upon the process configuration, including the use of micro-filtration (MF), ultra- filtration (UF), granular media filtration etc. This was put forward on the understanding that the adopted technologies achieve the necessary barriers to pathogen transport and that the assessed health and environmental objectives are satisfied.

A water quality specification was subsequently developed to mitigate those inherent risks remaining after the application of the treatment barriers and accompanying management controls. The specification provided estimates of the reduction that needs to be achieved through the application of barriers in the treatment process (human health) and upper limits on critical water quality parameters (environment).

3.3.4 EWRP under the 100-year inflow scenario The EWRP under the 100-year inflow scenario has been updated and recosted. Key elements of change in the costing were: • significant increases in pipe cost estimates, using unit rates for pipes that have been applied to the other major augmentation projects - desalination and north-south pipe. This change, based partly on observation of recent project costs interstate, has increased the ‘pipe’ component of cost of the EWRP by more than $700 million over the estimates made in the EWRP Feasibility Outcomes report. • incorporation of an additional ammonia treatment treatment plant at ETP to meet the water quality needs of the industrial users.

Water Recycling Options

• escalation of capital costs by 15% on 2006 figures to reflect recent industry experience • changes to discount rates in NPV calculations to make these consistent with those applied to other projects.

EWRP component CAPEX OPEX Annual volume of water $ billion $ billion delivered (GL) (NPC) (NPC)

Recycled Scheme 2.0 0.7 115

Release Scheme 0.7 0.2 90

3.3.5 EWRP under reduced inflow scenarios A permanent reduction in inflows to Gippsland catchments would reduce total water availability in the Latrobe Valley, and would likely change the scale of the EWRP.

For example, modelling done for the CRSWS and EWRP Feasibility Outcomes report indicates that a reduction in inflows reflecting the past 10-year average would reduce water availability in the Latrobe Valley by around 30%, which in turn would have several implications for the EWRP: • The EWRP could be an increasingly important source of water to make up for climate change losses, especially with respect to provision of water for key industries. • Alternatively, the Latrobe Valley industries would need to consider introducing water saving measures, which could include adoption of hybrid or dry cooling techniques for existing power stations, or identifying alternative sources of water. • Current requirements for environmental flows in the Latrobe Valley and the may need to be reconsidered.

One alternate EWRP scheme has been designed and costed based on the following assumptions: • Total water available in the Latrobe Valley could be roughly equivalent to the 2050 scenario outlined in the CRSWS, and therefore reduces to 115 GL per year • Industry would move quickly to introduce short-term water saving measures and in the face of continued water shortages, would also introduce permanent cooling technology changes, until their water requirements could be met within the region • Industry’s water usage in this scenario could reduce to around 80GL/year – this therefore is the size of the EWRP Recycled Scheme • The 80GL of water freed up is distributed via the Release Scheme as follows: - 60GL would be returned to Melbourne (via the Released Water Scheme) - an additional 9 GL is maintained to meet for future urban needs in Gippsland - 11 GL/year, representing the ‘balance’ of the water freed up under the proposal, is made available as additional environmental flows. • Where appropriate in the re-sized scheme, costs savings were identified in areas such as pipe sizes, pump sizes, operating and energy costs.

Water Recycling Options

Therefore, the Recycled Water Scheme was re-sized to transfer 80 GL to the Latrobe Valley, providing 80 GL to industry. The Released Water Scheme was re-sized to transfer 60 GL to Melbourne, and provides 9GL for urban needs and 11 GL for environmental flows.

This alternate is presented principally as a means of considering the potential costs of the EWRP under a range of foreseeable conditions. The EWRP could be constructed at any scale within the ranges presented, and would need to be subject to considerations of industry needs and urban and environmental flow requirements in the Latrobe Valley.

EWRP component Capex Opex Annual volume of water $ billion $ billion delivered (GL) (NPC) (NPC)

Recycled Scheme 1.4 0.5 80

Release Scheme 0.5 0.1 60

In the face of even more extreme climate change or continuing deep drought, securing supplies of water for Latrobe Valley power industries may become a more significant issue, and less water may be available for release to Melbourne.

A current study by the Department of Primary Industries is investigating options for water supply and use for Latrobe Valley power generation. This study is expected to identify potential short and medium term water savings of around 25-30% through changes to operating regimes (eg. ‘cycling up’) and alternative cooling technologies. The study will also provide an initial estimate of the capital and operating cost of introducing changes.

The feasibility work done to date on the EWRP provides an indication of the cost of providing between 80 GL and 115 GL of water to industry, as a stand-alone component (ie. without the Release Scheme bringing water back to Melbourne). This understanding of costs can be taken into account by the Latrobe Valley power generators in their investment decisions on new technologies.

3.3.6 Timelines The EWRP could be progressed and delivered to distribute recycled water soon after the upgrade of the ETP.

3.4 Potential benefits of the EWRP proposal

3.4.1 Securing water for cities, towns and industry for the future Implementing the EWRP could make available more than 100 GL/year (although less in accelerated climate change scenarios) to mitigate against water shortfalls generated through population and industrial growth, climate change and bushfires.

The EWRP potentially offers greater security for Gippsland towns as well as essential service industries such as the power industry.

Water Recycling Options

3.4.2 Water for rivers A proportion of the water made available through the EWRP could be allocated to help meet environmental water requirements of rivers. In particular the project could provide a permanent additional supply of water to the Latrobe River.

3.4.3 Improving the health of Lake Wellington There is an opportunity to improve the health of Lake Wellington, through the allocation of part of the released water as additional flows to the Latrobe River (which discharges to Lake Wellington).

3.4.4 Significant reductions in ocean outfall discharges Discharges to the ocean would be significantly reduced in volume, and nutrient discharges to the ocean would be reduced by approximately ten per cent.

Volume discharged – 2005 flows

After Eastern Water Current Recycling Proposal Ocean Outfall GL/yr GL/yr % Change

Boags Rocks 138 24 -80%

Dutson Downs 12 2 -83%

SWOP 7 17 143%

Total 157 43 -72%

Table 1: Impacts on discharge volumes

A further study was undertaken to assess the potential of recycling the remaining discharge at Boags Rocks that would exist after the implementation of the EWRP. Key findings from the study were: • New water recycling schemes have been identified that could reduce discharges at the Boags Rocks outfall to zero under all but extreme wet weather periods. However, the implementation of the majority of these schemes would be cost prohibitive. This study indicates that it would cost over $1.2 billion to recycle the discharge remaining at Boags Rocks following the implementation of the EWRP. • A number of local recycling schemes in the Mornington Peninsula and west Gippsland have potential to further reduce discharges through increased recycling. These options should be investigated in any further business case evaluation of the EWRP. • Boags Rocks outfall will always be required to cater for the peak flows during extreme wet weather or as a contingency measure for the failure of the EWRP recycling scheme treatment or transfer systems.

Water Recycling Options

3.4.5 Closure of the Gippsland Regional Outfall Sewer Under the Proposal, treated effluent transferred by Gippsland Water via the Regional Outfall Sewer to Dutson Downs treatment plant will be captured and recycled to industry. This will allow the 45 kilometre open sewer channel to be closed.

3.4.6 Increased economic development in the Gippsland Region The EWRP supports the continued economic revitalisation of the Gippsland Region. The project results in significant additional economic activity and employment from the construction of the required facilities, along with its on-going operation.

3.5 Key issues for further investigation The recent review of the EWRP has focused on updating the technical scope and financial costs of the proposal. If the project proceeds to the next phase of business case evaluation, design development and permitting, a number of matters would need to be investigated and resolved.

3.5.1 Industry requirements and agreements Industry demand for water will drive decisions on the scale, cost, value for money and potentially the required time to delivery of the EWRP.

Volume The Latrobe Valley industries have firm agreements with government and water authorities including contract and bulk entitlements to water, the latter expressed as a percentage of water availability in storages and run of river in the regional system.

Prior to the current drought, industry demands were met adequately by average inflows to Blue Rock Dam, Moondarra Dam and run of river in the Latrobe. Full entitlements exceeded actual usage.

The potential for climate change to reduce total water availability, and therefore industry’s share, has led to an investigation by the power generators and other major industries in the Latrobe Valley into opportunities to reduce their water usage.

In both the 10-year and 100-year inflow scenarios the EWRP could replace the full volume of water typically used by industry cooling systems, without the need for major technology or process changes. However, industry’s total demand for water from the EWRP will depend on whether it chooses to introduce water saving technology.

Further consultation is required with the Latrobe Valley industries to determine the most cost-effective means of meeting industry’s short, medium and long term requirements in the face of uncertainty about climate change, and the part that the EWRP could play in meeting those needs. These investigations should attempt to identify the ‘investment decision points’ in either water saving technologies or the EWRP or both.

Water Recycling Options

Quality Industrial plants have specific requirements for water quality. Work done for the EWRP Feasibility Outcomes report indicates that the combination of upgraded treatment at ETP and new plants located in the Latrobe Valley could adequately meet industry requirements. The quality of recycled water supplied has implications for the volume of water the plants could use.

The industrial plants are very large capital investments and the power plants are required to provide secure base electricity supply to Victoria. This matter warrants further investigations, trialling and confirmation of adequate water quality requirements and supply before implementation of the EWRP.

In particular further consultation with industry should clarify the need for any additional treatment to achieve adequate water quality, including reducing Total Dissolved Solids loads in recycled water.

New agreements with industry Industry’s bulk entitlements were established as part of the agreements when the power system was disaggregated and sold to private operators. In order to gain access to the water freed up by the EWRP, government would have to enter into new agreements with industry. The original EWRP envisaged a ‘trade’ whereby industry relinquished its bulk entitlements and the EWRP delivered substitute water at no net cost to industry. Some of industry’s access to water is subject to supply contracts with Gippsland Water.

Under some scenarios, the water that could be provided to industry could have significant additional value by securing water supplies. This value could be reflected in a financial contribution to the EWRP by industry, possibly through water pricing.

Any further consideration of these issues should lead to the development of the key commercial principles including how the recycled water supplied to industrial users could be priced and the impacts on their businesses in the context of the markets in which they operate. Similarly, implications for Gippsland Water need to be evaluated.

Consideration should also be given to the overall value/impacts of securing a more reliable supply of water for the Victorian generators, including the potential impacts on electricity prices and the Victorian economy.

Many options exist for the form, duration, value and rights under any new agreement. Further assessment by government and consultation and negotiation with industry is required to resolve the best form of agreement that meets the needs of industry and the EWRP.

3.5.2 Water availability in an altered climate Reduced inflows to Gippsland catchments would reduce the availability of water in Blue Rock Dam, Moondarra Reservoir and in the Latrobe River.

Any significant reduction in inflows could force reconsideration of allocations within the region, and would reduce the amount of water that could be released to Melbourne to augment potable supplies.

Water Recycling Options

Initial modelling done to evaluate the EWRP under the 10-year inflow scenario indicates a reduction of 1/3 in the ‘yield’ of the project. The cost of the project would reduce by approximately 10-20%. While this represents a significant saving in capital and operating cost, the unit rate cost of released water would be higher unless other system savings could be identified.

Further modelling should be done to evaluate the yield and costs of the EWRP under different climate change scenarios, including accelerated climate change or continuing deep drought. This modelling should include assessments of the needs of industry in these alternative scenarios.

3.5.3 Technical specifications The EWRP requires further design development to inform a full business case evaluation, and to confirm system configuration and locations for the purposes of environmental impact assessment.

This further design development would: • select a preferred scheme capacity • confirm pipe routes and sizes, pumping rates and energy requirements for the scale of the recycled water scheme finally selected • confirm treatment processes required to meet required water quality standards, taking into account the proposed treatment processes and effluent standards required of the ETP upgrade • confirm the design of upgraded discharge and outfall infrastructure • confirm water allocations within the Released Scheme to towns, environmental flows and Melbourne • confirm pipe routes and sizes, pumping rates and energy requirements for the scale of the released scheme finally selected • further refined project costs.

3.5.4 Environmental, social and economic issues A significant amount of work has been done at the desk-top level to evaluate the environmental, social and economic issues associated with the project.

As noted earlier, the project would offer genuine benefits to the environment and economy of the Gippsland Region by securing a source of high-value water for urban use, additions to environmental flows and to encourage future agricultural and industrial development.

Further investigation is required, once the final project scope is known, to identify and assess the potential adverse impacts of the EWRP, and measures available to avoid or mitigate those impacts, in particular: • quantification of impacts on flora, fauna and cultural heritage sites along pipeline routes and at plant locations, including options to relocate infrastructure to avoid these features • evaluation of the potential impacts of altered discharges to Bass Strait via the SWOP, and confirmation of the technical design of any altered outfall at McGaurans Beach

Water Recycling Options

• evaluation of the proposed treatment technologies against any relevant environmental, public health and occupational health standards • identification of opportunities to minimize energy use and to acquire greenhouse gas emission offsets to ensure the project is carbon neutral.

Further consultation is required with regulatory authorities to clarify approval requirements and stakeholder consultation processes required for the EWRP.

Further consideration is required of the legal basis of recycled water being used as permanent additions to the Environmental Water Reserve.

Further analysis is required of the potential benefits of additional environmental flows resulting from the EWRP and optimising the volume and value of water released to the environment as part of the project.

Research should be conducted into any potential social and economic issues, including the implications of any changes to current irrigation or other use of water within the area of operation of the EWRP, attitudes to use of recycled water, the economic value of securing water supplies for both Gippsland and Melbourne and opportunities provided for further growth in the region that could be supported by the EWRP.

3.5.5 Procurement options The EWRP is a very large capital project with moderate long-term operating costs and a potentially secure demand base.

It has potential for the involvement of private sector financing through models such as public-private partnerships or alliancing. This investigation would need to assess issues for ownership and impacts or changes required to the roles of relevant water authorities.

Further investigation is required to quantify the value-for-money outcomes that could be achieved under public and private governance and financing alternatives.

These matters would be assessed in a Business Case.

Water Recycling Options

4.0 Substitution of environmental flows: Yarra River

4.1 Summary

Up to 320ML/day (and up to 100GL per year) of highly treated recycled water effectively meeting drinking water standards would be piped from ETP to the Yarra River below Yering Gorge, substituting environmental flows.

Approximately 45 GL of additional water could be drawn from the Yarra further upstream, into Sugarloaf Reservoir, for augmentation of Melbourne’s water supply.

The Winneke Treatment Plant would be upgraded to ensure drinking water quality of the additional supply is maintained.

Capex Opex Annual volume Annual volume $ billion $ billion delivered to Yarra delivered to (NPC) (NPC) River (GL) Melbourne (GL)

ETP to Yarra 1.3 0.8 100 45

4.2 Project overview This option involves the transfer of up to 320 ML/day (up to 100 GL/year) of highly treated recycled water to the Yarra River downstream of the Yering Gorge pumps, to supplement environmental flows and provide the opportunity to harvest additional river water upstream, via the pumps, to Sugarloaf Reservoir.

The available recycled water from ETP (treated to tertiary and Class A standard under the proposed ETP upgrade works) would require further treatment through provision of additional pathogen and contaminant barriers. The recycled water produced would effectively be of drinking water standard and meet environmental requirements, including for nutrients, for discharge to the Yarra River downstream of Yering Gorge.

This option is likely to require the additional treatment at ETP being considered as part of the planned upgrades to remove residual colour and odour impacts as part of the overall treatment process train to achieve the water quality specification to enable discharge into the Yarra River. A decision in 2009 on whether or not this treatment concept will be included as part of the ETP upgrade will therefore be an important consideration with respect to the potential costs for additional treatment works associated with a potential ETP to Yarra River option.

Proposals to use high quality recycled water as a replacement for stream environmental flows are not new. Such a scheme is presently under construction in Sydney. The Replacement Flows Project involves the construction of an Advanced Water Treatment Plant (AWTP) to treat effluent collected from a number of regional wastewater plants and discharge of the high quality recycled water to the Penrith weir on the Hawkesbury-Nepean River. This means that water currently released from Warragamba Dam to the Hawkesbury-Nepean River will be retained, thereby increasing the yield of the Sydney system by 18 GL/year.

Water Recycling Options

In relation to the ETP option considered here, the principal elements of the recycled water scheme would be expected to include: • further advanced treatment of Class A recycled water at Eastern Treatment Plant • pumped transfer by a pipeline of this high quality recycled water from ETP to the Yarra River below Yering Gorge • improvements to Winneke Water Treatment Plant.

4.3 Project components

4.3.1 Further advanced treatment at ETP The proposed overall treatment process train (including the further advanced treatment processes in addition to the planned tertiary treatment upgrade components) at ETP is shown in Figure 6.

The ETP advanced treatment output would be sized for 320 ML/day. This is based on: • expected Class A effluent volumes that would be available following the planned ETP upgrade, taking account of: - existing recycled water supply commitments - seasonal patterns of inflows to ETP - expected impacts of ongoing water conservation programs on inflows to ETP - impacts of long term drought on reducing inflows to ETP - impacts of drought related water restrictions on reducing inflows to ETP - 85% recovery from the further advanced treatment of the available Class A effluent volumes.

ETP

Coagulation NITROGEN Lime/CO REDUCTION 2

$100M Cl 2

DENITRIFICATION FILTER GMF O3/BAC MF/RO UV 320 ML/D 320 ML/D 320 ML/D To Transfer Pump Station

BRINE OUTFALL

EXISTING OR PLANNED

Figure 6: ETP advanced treatment

Water Recycling Options

The available recycled water from ETP (treated to tertiary and Class A standard under the proposed ETP upgrade works) would require further treatment through provision of additional pathogen and contaminant barriers. In addition to the planned ETP upgrade, additional advanced treatment steps would be required to provide high quality recycled water suitable for discharge to the Yarra River. The proposed treatment steps to achieve this (and their functions) are set out in Table 3. The recycled water produced by the proposed treatment train would effectively be of drinking water standard and meet environmental requirements, including for nutrients, for discharge to the Yarra River downstream of Yering Gorge.

Treatment step Function

Biological Nitrogen Removal involving Remove ammonia; provide nitrification/ reconfiguration of existing aeration tanks denitrification to reduce total nitrogen and introduction of additional recycle levels. streams

Denitrifying filters To further reduce total nitrogen. The purpose is to minimise nutrient addition to receiving waters.

Coagulation (new) and To reduce phosphorus levels to minimise Granular Media Filters (assumed existing impacts on receiving waters of nutrients. following planned ETP upgrade) This step has an additional benefit of reducing colour and organics levels in the recycled water.

Ozone/ To remove trace micropollutants such as Biological Activated Carbon (BAC) Filters pharmaceuticals and other potential endocrine disruptors. This step also reduces total organic levels and colour, improves odour, and provides an initial disinfection barrier. It also improves the performance of downstream processes.

Microfiltration/Reverse Osmosis Membrane To remove pathogens, particulates, organic Filtration molecules, dissolved metals and salt. The concentrated waste would be discharged to ocean through a dedicated brine outfall and associated diffuser system

UV Disinfection (assumed existing following Additional disinfection barrier. planned ETP upgrade)

Chlorination Final disinfection barrier for viruses. Provides residual disinfection for en-route recycled water users. Keeps pipelines clean.

Lime/Carbon Dioxide Dosing For pH neutralisation.

Table 3: ETP advanced treatment processes

The proposed treatment train would result in a concentrated waste stream from the reverse osmosis (RO) treatment step, requiring a dedicated brine outfall. Any new or altered outfall would require works approval from EPA Victoria.

The planned ETP tertiary treatment upgrade scheduled for completion in 2012 will include either granular media filtration (GMF) or membrane filtration (MF) technology, depending on the outcomes of the trials currently underway and further concept development and design. The upgrade works will also include an ultra violet (UV) disinfection facility. It has been assumed for the purposes of this pre-feasibility assessment that GMF and UV will be implemented as part of the planned ETP upgrade; these components have therefore not been costed as being driven by the

Water Recycling Options

need for further advanced treatment to achieve the water quality requirements for discharge into the Yarra River. Alternatively, if the ETP tertiary upgrade proceeds with implementation of MF technology instead following the outcomes of the trials, the further advanced treatment process train would require installation of a GMF process step rather than an additional MF process step as currently assumed.

Additional treatment to remove residual colour and odour impacts at the existing ocean discharge point for the South East Outfall at Boags Rocks may or may not be included as part of the ETP upgrade works (also pending the outcomes of the trials). Such a treatment process is expected to be required as part of the overall treatment process train to achieve the water quality specification to enable discharge into the Yarra River under this recycled water option. A decision in 2009 on whether or not this treatment concept will be included as part of the ETP upgrade will therefore be an important consideration with respect to the potential costs for additional treatment works associated with a potential ETP to Yarra River option.

4.3.2 Transfer infrastructure from ETP to Yarra River The proposed transfer system for the highly treated recycled water would comprise the following: • tank at ETP (50 ML) • transfer Pump Station, 320 ML/D at 170 metres head • pipeline from ETP to the Yarra River (below Yering Gorge Pump Station), 1750 millimetre diameter at a length of 57 kilometres • dechlorination prior to discharge to the Yarra River • river discharge facility and associated infrastructure.

A potential pipeline route from ETP to the Yarra River has been investigated by South East Water and and is shown in Figure 7. It should be noted that, with this route, a hill at 44 kilometres and at a level 125 metres located at Ervin Road controls the hydraulics.

The proposed transfer system provides for up to 320 ML/d (allowing up to 100 GL/year) of high quality recycled water to the Yarra River downstream of Yering Gorge.

Water Recycling Options

Figure 7 Proposed ETP to Yarra River Pipeline Route

4.3.3 Winneke Water Treatment Plant requirements Winneke WTP has an existing capacity of 560 ML/d. This capacity would have been sufficient to accommodate an increased annual throughput expected to be available as a result of increased capacity to harvest water from the Yarra River (determined from water resource modelling to be in the order of an extra 45 GL/year). However the Sugarloaf Interconnector will be taking up the remaining capacity at Winneke and hence the introduction of recycled water in this area will require an upgrade to the capacity at Winneke or a new plant.

The resulting increased throughput of Yarra River water through Sugarloaf Reservoir is likely to lead to reduced detention time, which, in addition to the proportional reduction in throughput from Maroondah Reservoir via the Maroondah Aqueduct, may add to drinking water quality risk. As such, the following risk management measures at Winneke would be prudent to ensure adequate drinking water quality is maintained: • Powder Activated Carbon Dosing (PAC) as a barrier to algal taste and odour • Ultraviolet Radiation (UV) as an extra barrier to protozoa breakthrough • The additional PAC dosing and UV process trains at Winneke would be sized to treat water up to 560 ML/d.

Such upgrade process arrangements at Winneke WTP are shown in Figure 8.

Water Recycling Options

WINNEKE

Powdered Cl 2/Lime/Fluoride Activated Alum Carbon

TRANSFER PIPE 150 GL/y EXISTING EXISTING UV CWS FROM CLARIFIERS FILTERS SUGARLOAF (No. 14) 560 ML/D 200 ML 150 GL/y (TWL 185) TWL 176.5m 560 ML/D 560 ML/D RESERVOIR NEW RELIFT PUMP PUMPS STATION 560 ML/D 600 ML/D @ 15 m @ 55 m

EXISTING

Figure 8 Indicative Winneke WTP Upgraded Treatment Process

4.3.4 Overall scheme The overall scheme involving further advanced treatment of Class A standard effluent at ETP, transfer of the high quality recycled water to the Yarra River below Yering Gorge as replacement environmental flows, and the upgrade of the Winneke WTP to accommodate increased Yarra River abstraction is shown in Figure 9.

WINNEKE ETP

320 ML/D ADVANCED TREATMENT AT ETP

(SEE FIGURE 1)2) De Cl 2 CURRENT YIELD TREATMENT 100 GL/y EMERGENCY ADDITIONAL AT DIVERSION YIELD 50 GL/y TRANSFER TO OUTFALL WINNEKE PIPE SUGARLOAF WTP RESERVOIR 150 GL/y TANK 100 GL/y (SEE FIGURE 3)4) 50 ML 96 GL

TWL 10m 1750 mm Ø TWL 178 m 57 km EXISTING 320 ML/D YERING GORGE P.S NEW Hill @ Ervin TRANSFER Rd.: 125m @ 1000 ML/D PUMPS 44 km @ 145 m 320 ML/D @ 170 m LOCAL Head REUSE EXTRA ENVIRONMENTAL FLOW UP TO 50 GL/y

YARRA RIVER WL: 60 m

EXISTING

Figure 9: Summary concept for high value recycled water discharge to the Yarra River below Yering Gorge

Water Recycling Options

4.3.5 Scheme capacity and potential additional water supply yield The estimated reliable availability of highly treated recycled water from ETP is estimated to be around 100 GL/year for the concept scheme proposed, assuming a scheme transfer capacity of 320 ML/day.

Preliminary REALM water resource modelling has confirmed that, with substitution for environmental flows downstream of Yering Gorge, the additional yield that could be harvested into the water supply system from the Yarra River would be around 45 GL/year. Amongst other assumptions the REALM modelling maintained: • a minimum passing flow past the Yering Gorge Pumps of 100 ML/d • level of service criteria as per the Bulk Water Supply Agreements with the retail water businesses • full Yarra environmental flows provided and meeting the Government’s commitment to increasing environmental flows by 18 GL in the Thomson.

The production at ETP of up to 100 GL/year of high quality recycled water also has the following potential benefits: • ability to supply industrial and other potential users en-route between ETP and the Yarra • enhancement of environmental flows in the Yarra River beyond mere replacement flows • significant reduction of effluent discharge down the South Eastern Outfall.

Additional modelling is required to reflect the full Melbourne Augmentation Program and updated assumptions.

4.3.6 Operational regimes In relation to the proposed transfer system operation, consideration would need to be given to: • provision of the capability to cease discharge to the Yarra River during wet weather flow events so as not to exacerbate potential local flooding • capability to reduce recycled water flow to the river during summer, if necessary, to mimic the natural pattern of environmental flows • capability to cease transfer if high value recycled water from ETP is not within specification • PAC dosing at Winneke WTP would not ideally occur all year, but only when algal taste and odour events occur. An assumption of PAC treatment for one- third of annual throughput has been made in the operating cost estimates for this concept.

Water Recycling Options

4.4 Project costs and timelines

4.4.1 Estimated scheme costs Based on the broad definition of a scheme to replace environmental flows to the Yarra River (downstream of Yering Gorge) using high value recycled water from ETP, a preliminary desktop cost estimate (± 40%) has been prepared.

This cost estimate has a number of uncertainties relating to the following: • The high rate of construction activity in the water industry and costs are escalating rapidly. • The wide variation in tendered costs, which have been seen in the market. • The estimate has been based on a desktop review only without any functional design of the scheme. • Additional investigations including geotechnical, flora, fauna, and heritage review are not available. • Further discussions with key stakeholders are required. • Due to the many uncertainties, a contingency of 40% has been adopted. • The preliminary cost estimate presented has been developed solely for the purpose of comparing and evaluating competing options. They are sufficiently accurate to serve this purpose. They cannot, however, be used for budget- setting purposes as common elements between options may have been omitted and/or the works not fully scoped.

Cost estimates will be better defined following further project development as part of a Business Case.

4.4.2 Capital costs The capital cost of this option has been estimated at $1.3 billion NPC based on the currently preferred route and scheme components outlined below.

Cost of further investigations Significant further investigations and studies, as well as consultation, would be required prior to proceeding to an implementation phase for this concept. The nature of these investigations is outlined briefly below in section 4.6: Key issues for further investigation.

An allowance for these costs has been made.

Pipeline • Pipeline rates adopted match rates used for the various other Melbourne Augmentation Program options currently being considered. Pipe costs have also been based on route assessments outlined in a report by South East Water included in the Appendices to this report.

ETP treatment • based broadly on tender prices for other current major water projects e.g. Western Corridor ().

Water Recycling Options

Winneke WTP • based on recent tender prices adjusted for size.

Transfer pumps and tanks • based on standard cost tables updated.

4.4.3 Operating costs The estimated operating costs for the concept scheme are in the order of $70 million per year or $0.8 billion NPC.

Significant components of cost include: • membranes, chemicals and energy use at ETP • additional costs of treatment and energy at Winneke Treatment Plant • pumping of water from ETP to Yarra River.

4.4.4 Preliminary estimated project timelines The project could be constructed relatively quickly – within three years of achieving required approvals. However, this option is likely to require significant additional environmental and public health investigations, as well as public and stakeholder consultation processes, prior to the issue of required statutory approvals.

The likely earliest timing for implementation of this scheme is soon after the upgrade of ETP.

4.4.5 Contribution to water supply for Melbourne The assumed reliable availability of highly treated recycled water from ETP is estimated to be around 100 GL/year for the concept scheme proposed, assuming a scheme transfer capacity of 320 ML/day.

The additional yield that could be harvested into the water supply system from the Yarra River would be around 45 GL/year.

This would make a significant contribution to Melbourne’s water supply, but is dependent on available flows in the Yarra River upstream of Yering Gorge and, therefore, prevailing climatic conditions in terms of security of supply.

4.5 Environmental and social issues

4.5.1 Pipeline route One identified route for the pipeline generally follows , Tarralla Creek and Brushy Creek reserves and, therefore, there is the potential to impact on

Water Recycling Options

environmental values associated with these creeks. Areas of flora and fauna significance were identified from maps available from the DSE website.

There are many sites of biodiversity significance along the Dandenong Creek, but these generally can be avoided by locating the pipe in rural land avoiding significant sites and riparian zones.

The section of the Dandenong Creek between Wellington Road and Burwood Highway contains many areas of flora and fauna significance, particularly around and within 100 metres on either sides of the creek. There is sufficient space between the creek and EastLink motorway, where the land is currently used for grazing and agricultural purposes. It is practical to construct the pipeline within these open spaces away from the sensitive areas. However, the pipeline will be located on slightly higher ground.

One part of the Tarralla Creek Reserve has been identified as containing endangered flora and fauna. As this section of the pipeline will be constructed by boring, it is unlikely to impact on the biodiversity.

The land, gorge and riparian areas along the Yarra River are very sensitive from an environmental perspective, and the precise location of the pipeline and discharge point cannot yet be determined. Further technical and environmental studies will be required to determine the potential impacts and infrastructure requirements.

4.5.2 River discharge location A discharge location up to two kilometres downstream of Yering Gorge, so that no recycled water can be pumped into Sugarloaf Reservoir, was considered for this option. However, this will result in the stretch of river downstream of the pumps experiencing very low flows based on the 100 ML/day minimum passing flow when pumping from the river.

This stretch of river contains a number of significant values, including the presence of threatened native fish that could be impacted by reduced flows. While the stretch of river impacted is relatively short compared to the length of river over which suitable habitat is present of native fish, a reduction in flows, even for a short distance, may have significant implications for fish passage and downstream transport of organic material that is important for driving aquatic food webs.

4.5.3 Receiving water quality implications

The State Environment Protection Policy (Waters of Victoria) (SEPP) defines the beneficial uses and sets water quality criteria to protect the most sensitive uses in various segments in the Yarra River (Schedule F7) and Port Philip Bay ( Schedule F6) – see table below. Natural aquatic ecosystems are the most sensitive beneficial use in terms of water quality; protecting this beneficial use will indirectly protect other beneficial uses with less demanding water quality requirements.

Water Recycling Options

Beneficial use Urban Upper Yarra Hobson’s Port Bay

Segments of Yarra defined in SEPP 5, 6 7

Maintenance of natural aquatic

ecosystems and associated wildlife

Modified ecosystems X

Highly modified ecosystems with some X X X habitat values

Passage of indigenous Fish X X X

Maintenance of indigenous riparian X vegetation

Water based recreation

Primary contact (e.g. swimming, water X* X skiing)

Secondary contact (e.g. boating, fishing) X X X X

Aesthetic enjoyment (e.g. walking by the X X X X water)

Commercial and recreational use of X X X X edible fish and crustacea

Potable water supply X

Agricultural water supply

Stock water X

Irrigation X X

Other commercial purposes

Industrial water use X X X X

Navigation and shipping X X X

* value is an objective for the tributaries of the Yarra River Table 4: Protected beneficial uses in the Yarra River (Schedules F7 for Waters of the Yarra Catchment, and Schedule F6 Waters of Bay)

Under clause 31 Management of wastewater reuse and recycling in the SEPP, provided EPA Victoria is satisfied that wastewater can be treated and managed to a level that will protect beneficial uses, the discharge of that wastewater to surface waters to provide water for the environment or other uses, is an acceptable form of re-use. The delivery of this water should consider such factors as seasonality, temperature and discharge rate. Consistent with this, the State government’s white paper Securing Our Water Future Together has an action to develop guidelines for the use of recycled water to provide environmental flows for waterways. The proposed guidelines would greatly assist the development of this option.

For initial evaluation of this option, it was assumed that effluent will be treated to Class A standard as part of the ETP Upgrade and further advanced treatment will achieve high quality recycled water of effectively drinking water standard. For the purposes of this assessment, preliminary assumptions were made on the quality of the recycled water for a range of parameters.

Water Recycling Options

Based on these preliminary assumptions, current standards for ammonia (NH3-N), nitrate (NO3-N) and some heavy metals concentrations in the recycled water would exceed the SEPP objectives for the Yarra River. The alkalinity assumed in this preliminary assessment is also very low and has the potential to reduce the pH buffering capacity of river water. Turbidity and total dissolved solids (TDS) in the recycled water are significantly below SEPP criteria.

The current water quality in the Yarra River is considered moderate around Warrandyte and poor further downstream. In particular, the SEPP criteria for dissolved oxygen, turbidity, nutrients and some heavy metals are often exceeded. Despite these frequent SEPP exceedences, the concentration of ammonia, arsenic, cadmium, nickel and zinc assumed for the recycled water for this assessment would still be greater than the background concentration in river water.

Without further improvement to the quality of recycled water that has been assumed for the purposes of this preliminary assessment, the high quality recycled water could have the following adverse impacts: • Under circumstances when recycled water from ETP contributes a significant proportion of flow to the Yarra River (70 to 80% during summer low flow periods), the elevated ammonia concentration in the recycled water has potential for impacts on native fish and may also be converted to a bio- available form of nitrogen with consequent potential for increased algal and macrophyte growth. The low alkalinity means that river water will be susceptible to rapid fluctuations in pH, for example associated with rapid photosynthesis. A small increase in pH can increase effects of ammonia. In particular, investigations should take account of the value of this reach of the river as a key drought refuge for native species, including the best remaining population of the threatened Macquarie Perch in Victoria. • Very low turbidity in the recycled water has the potential to increase water clarity and light penetration with consequent risks of increased algal and nuisance macrophyte growth. • Low salinity is unlikely to pose a risk to aquatic biota, although dosing with minerals and inorganic and organic material should be further investigated to balance salinity, turbidity and organic matter content during periods of time when recycled water contributes a significant portion of river flow.

However, the treatment process train outlined for the ETP to Yarra River option can be designed and implemented to achieve relevant SEPP standards for ammonia, nitrate and heavy metals, to reduce or avoid these impacts. Additional treatment steps to those outlined for the proposed advanced treatment processes are not expected to be required. Rather, they can be designed and operated to achieve the required water quality standards.

Therefore, the preliminary investigations have identified the key water quality issues that would need to be addressed in further development of the project.

In addition, alkalinity adjustment is a standard component in water treatment processes and would be implemented as part of the overall treatment process train as required to ensure the alkalinity requirements for discharge to the river are met.

Bio-available nitrogen (NOx-N) and phosphorus (PO4-P) are relatively low in the recycled water and are lower than the typical concentrations recorded in the Yarra River. This results in potentially lower nutrient loads in the river and to Port Philip Bay.

There is some uncertainty regarding the potential ecological risks associated with other toxicants and treatment by-products. A comparison of the treatment specification and the ANZECC water quality guidelines indicates that most

Water Recycling Options

compounds expected in the recycled water will be in concentrations less than the trigger levels for the protection of slightly to moderately disturbed ecosystems. However, there are no specific criteria for some compounds such as nonylphenol. These require further investigation to confirm concentrations in recycled water and specific risks in receiving waters.

4.5.4 Environmental flow implications Monthly flows downstream of Yering Gorge and at Warrandyte and Chandler Highway with the addition of recycled water downstream of Yering Gorge have been modelled by Melbourne Water. In modelling flows a minimum flow of 100 ML/d was required to pass downstream from the Yering Gorge pump station to the point where ETP water is proposed to be discharged to the river (approximately two kilometres downstream of the pumps). A constant 320 ML/d of ETP water was then added to the river.

The addition of recycled water from ETP will substantially increase flow volumes downstream of Yering Gorge and, under accelerated climate change scenarios, could help to achieve minimum environmental flow recommendations through the lower reaches of the Yarra River at Warrandyte and Chandler Highway. It is difficult to determine if fresh and high flow components of the recommended flow regime will also be met because monthly data was used in the current assessment and daily data is required to explicitly test compliance with fresh and high flow recommendations. However, flow exceedence plots indicate that higher flows occur at both Warrandyte and Chandler Highway in response to ‘spills’ from upstream passing Yering Gorge and from ‘unregulated’ tributary inflows downstream of Yering Gorge. Hence it is likely that at least some of the fresh and high flow recommendations will be delivered under the modelled regime. In addition, a 17 GL/year Environmental Water Reserve is to be retained in storage to contribute to fresh and high flow events above those that occur in the modelled regime, further increasing the likelihood of the full range of fresh and high flow recommendations being met at Warrandyte and Chandler Highway.

However, immediately downstream of Yering Gorge there will be a stretch of river (approximately two river kilometres) where environmental flow recommendations are not met. Flows in this reach will be a minimum 100 ML/d with occasional higher ‘spills’ from upstream that are not captured by the pumps at Yering Gorge. The reach of river from Yering Gorge to Warrandyte contains significant environmental values, including the confirmed presence of three native fish species listed on State and Commonwealth threatened species legislation (Australian grayling, Murray cod and Macquarie perch). Maintenance of suitable flow conditions is critical to the survival of these species. In particular, Australian grayling require high flows in autumn to provide a spawning cue and to transport eggs and larvae downstream to the estuary. Even a short section of river with very low flows has the potential to interrupt the delivery of important flow components and will also interrupt the continuity of flows required to transport eggs and larvae from upstream reaches. A key requirement of the environmental flow recommendations for the Yarra River is that fresh and high flow components be allowed to progress the entire length of the river from upstream to downstream reaches in order to maintain longitudinal connectivity and transport of eggs, larvae and organic material.

Reduced flow continuity through the gorge may also interrupt fish migration patterns. Several native fish species migrate from the estuary and lower freshwater reaches to mid and upper reaches at various times during the year, possibly in response to high flow events.

These matters require further investigation to determine appropriate management and mitigation measures.

Water Recycling Options

4.5.5 Implications for the marine environment at Boags Rocks Assuming that most of the dry weather flow from ETP is diverted to the recycling scheme, only tertiary treated wet weather flows and minor residual flows will be discharged at Boags Rocks. As a result, improvements in the marine environment are expected including significantly reduced extent of ecological toxicity from freshwater effects and, therefore, reduced impact on marine life allowing for some recovery, and reduced odour.

However, a brine outfall will be required to dispose of the concentrate from the reverse osmosis process that is part of the advanced treatment process required to produce recycled water of drinking water standard. The extent and nature of the outfall and the need for further treatment of the brine needs to be investigated and a configuration to minimise impacts on the marine environment would need to be designed.

Any alteration to the discharge or outfall at Boags Rocks resulting from this project may require an EPA works approval.

4.5.6 Community concerns The community, stakeholders and interest groups will need to be consulted on the benefits of the option , and issues and concerns that need to be addressed. Social considerations include: • Concerns about the impacts of construction of the recycled water pipeline along waterway reserves and adjacent to Yering Gorge particularly on existing community uses and areas of natural and biodiversity significance. • Views and/or concerns about positive and negative impacts of recycled water on the health of the Yarra River, environmental and amenity benefits from reduced treated effluent discharge to Bass Strait at Boags Rocks, and management of brine waste from the advanced treatment process. • Concerns about suitability of water quality and flow regimes for water-based recreational activities such as aesthetic enjoyment, swimming, boating and canoing, and for irrigating school grounds and golf courses, industrial use, and stock and domestic use

4.5.7 Public health With regard to the safety of the recycled water from a microbiological perspective, the treatment processes involving the Class A upgrade and advanced treatment to drinking water standard will produce extremely high quality water, suitable for irrigation and direct personnel contact. With the implementation of a HACCP based risk management framework for ensuring ongoing production of the required water quality, there can be a high level of confidence in there being low concerns linked to microorganisms.

Organic compounds are also expected to be of low concern. A recent risk assessment was undertaken for the Western Sydney Replacement Flows Project, with the assessment including relatively sensitive end-uses such as downstream use for drinking water.

Water Recycling Options

4.6 Key issues for further investigation If the use of highly treated recycled water to substitute for environmental flows in the Yarra River below Yering Gorge were to be further considered as an option for supplementing water supplies to Melbourne, significant further investigation and studies would be required to develop such a scheme beyond the preliminary high level concept considered here.

Key studies and investigations would include: • stakeholder and community consultation to ensure that views and concerns are identified and taken into consideration in the further development of the option • comprehensive catchment risk assessment for wastewater received at ETP, and subsequent development and implementation of a management program as required • detailed assessment of the environmental flow implications of the project, in particular: - evaluating environmental flow requirements under different climate change scenarios - quantifying the benefits of any additions to environmental flows from this option - understanding relationships with other strategies to deliver environmental flows to the Yarra - evaluating the potential impacts of too little or too much water being made available to the different stretches of river • detailed water quality and toxicology studies to confirm suitability of water for environmental release to the Yarra River − Confirmation of the expected levels of inorganic compounds in treated water, relative to the water quality objectives and background concentrations in the river; − Detailed ecological risk assessment based on typical and peak levels of organic compounds in the treated water; − Further human health risk assessment to confirm that compounds such as endocrine disruptors and disinfection by-products are not of concern. These compounds were not covered in detail in the Western Sydney Replacement Flows Project; − Confirmation of the treatment process that would be used in the program, to enable quantification of the expected removal of key pathogens, thereby enabling a site specific quantitative microbial risk assessment. − Investigation of technical options to address identified recycled water quality issues. • treatment process train pilot testing to confirm the appropriate ETP treatment train • further modelling and assessment of scenarios of recycled water discharge, river water extraction and minimum flows downstream of the pumps to assess environmental impacts and develop flow regimes and technical options to protect biodiversity and ecological processes in the section of the river between the Yering Gorge pumps and the recycled water discharge point

Water Recycling Options

• detailed investigation of the potential environmental impacts at the river discharge point, as well as development of infrastructure options to appropriately address these impacts • further more detailed investigations of the proposed recycled water transfer pipeline route, including addressing planning requirements and related approvals processes • investigation of Flora/Fauna/Heritage and other environmental issues associated with the scheme and development and implementation of appropriate management programs as required. In particular, any relevant Heritage River requirements and obligations should be investigated and addressed. • further assessment of the specific infrastructure requirement implications if such a scheme were to be introduced in combination with one or more other major drinking water supply augmentation schemes. This work would need to include consideration of capacity issues relating to: − Yering Gorge pumps − Sugarloaf reservoir − Winneke water treatment plant − transfer system capacity − demand distribution within the supply system • further more detailed water resource modelling to more accurately determine the scheme’s potential impacts on the Melbourne supply system and hence confirmation of the estimated incremental system yield • detailed assessment of the options for waste stream/brine handling and disposal • investigation of new high value water recycling opportunities that exist or may arise along the pipeline route between ETP and the Yarra River • further concept and feasibility assessment as well as functional design work on the proposed scheme to improve definition, scope and costing certainty • further refinement of likely project costs, program and overall timeframes • assessment of project delivery options including options for ownership operations and financing.

Water Recycling Options

5.0 Other options

5.1 Increased commercial reuse of recycled water The upgrade of the ETP recycled water to Class A standard may lead to increased local demand for recycled water from a range of local users on the Mornington Peninsula and West Gippsland, including residential developers, agriculture (eg. intensive horticulture), open space management (golf course, parks and gardens) and industry (eg. the Dandenong industrial zone.)

Government has committed to substitution of potable supplies by recycled water by 10 GL across Melbourne by 2030. South East Water has identified opportunities for an additional 4-5 GL of recycled water use in future urban developments, for use in gardens and toilets, and has plans underway to deliver this outcome.

Already, up to 5 GL of water annually is used in local reuse schemes such as the Eastern Irrigation scheme. It is possible that this or other irrigation schemes could use more in future, particularly after the quality of recycled water from the ETP is upgraded.

Typically, supply of recycled water to new development or existing irrigation users is more cost-effective than retro-fitting supply to existing users, but new high-volume water users may exist in the south east region that warrant further consideration.

Future investigations into options for reuse of ETP recycled water should include consideration of options to increase local reuse of high quality treated water.

5.2 Indirect potable reuse A number of countries and jurisdictions use recycled water as an addition to drinking water supplies – this is known as ‘indirect potable reuse’ (IPR). IPR can offer a potential new source of water that is relatively protected from the impacts of climate change.

Places that currently use IPR or propose to use IPR are: • Three water treatment plants in Singapore produce high quality recycled water using a combination of traditional sewage treatment, micro-filtration and reverse osmosis, followed by disinfection. The recycled water meets relevant World Health Organisation and USEPA standards for safe drinking water and is in fact cleaner than most of Singapore’s existing supply. • The plants supply about 5 ML per day into the potable water supply system, meeting about 1% of Singapore’s daily demand. Singapore plans to increase this percentage to 2.5% by 2011. • In Washington DC, highly treated wastewater from the Upper Occoquan Sewage Authority plant supplies about 20 per cent of the inflow into the Occoquan Reservoir. • Essex in the UK also recharges its water supply with purified recycled water. • In Los Angeles the Mondebello Forebay Groundwater Recharge project replenishes the groundwater basin underlying the greater Los Angeles metropolitan area and has been in operation since 1962. A similar project has been in operation in Orange County since 1976.

Water Recycling Options

• Veurne-Ambacht - a tourist region on the coast of Belgium - gets its water supply from groundwater basins which are recharged with purified recycled water. • So-called ‘unplanned’ indirect potable reuse occurs in many major cities around the word. For example, major towns such as Oxford, Reading and Swindon discharge their treated wastewater into the River Thames upstream of water supply off takes servicing London • Queensland aims to introduce recycled water to drinking supplies by the end of 2008. The water will be treated through a seven-barrier system comprising treatment technologies and environmental buffers, with the treated water added to other supplies in the Wivenhoe Dam.

IPR has improved security of supplies in these places and has been able to meet relevant local and international drinking water and public health standards.

IPR is not currently supported by Victorian Government policy. However, it would be prudent to monitor advances in technology and the experiences of those places using IPR as a technology.

Water Recycling Options

6.0 Appendices

Water Recycling Options

Water Recycling Options