Coliban System. Water Supply Demand Strategy. Final Report March to 2060

Transcription

1 Coliban System Water Supply Demand Strategy 2011 to 2060 Final Report March 2012

2 TABLE OF CONTENTS Executive Summary 4 1. Introduction 7 2. Overview Key Features How Water is Delivered to each Town Customer Profile Recent Experience Water Supply Raw Water Demand Urban Water Demand Rural Water Demand Total Raw Water Demand Water Quality Waterplan 2055 Review Levels of Service Climate Change / Variability Scenarios Demand Forecast Current System Demand - Baseline Demand Urban System Water Demand Baseline Demand Rural System Water Demand Baseline Demand Current Total Raw Water Demand - Baseline Demand Future System Demand Population and Demand Growth Residential Population Growth Non-Residential Demand Growth Total Growth in Residential and Non-residential Demand Environmental Demand Climate Change Impact on Demand Behaviour Change Improved Water Quality Summary of System Demand Impacts Supply Forecast Headworks Storage Evaporation Catchment Management 28 Page 2

3 8. System Performance Evaluation Southern Coliban System Coliban Northern System Combined Coliban System Demand Reduction Measures Permanent Water Saving Rules (PWSR) Reduction of Operational Water Reduction of Rural System Losses Water Saving Incentives and Community Education Pricing Incentives Summary of Demand Reduction Measures Additional Supply Measures Temporary Water Market Permanent Water Market Connect Castlemaine to Bendigo Additional Use of Recycled Water Additional Water Private Rain Water Tanks Alternative Water Sources Water Quality Measures Options Analysis Demand Reduction Additional Water Options Summary Management of Risk and Uncertainty General Murray Darling Basin Plan Proposed Actions Short-term Actions Long-term Actions Community & Stakeholder Engagement 43 APPENDICES Appendix 1: Appendix 2: Alternative Water Atlas Long List of Supply Options Page 3

4 Executive Summary Introduction Coliban Region Water Corporation is a state owned water authority that provides water and wastewater services to a region with a population of 140,000 people, across 16,550 square kilometres of Central and Northern Victoria. The service area covers 49 towns in nine separate supply systems of which the Coliban Northern system and Coliban Southern system are two. The Water Supply Demand Strategy (WSDS) identifies the best mix of measures to maintain a balance between the demand for water and the available supply in urban supply systems, now and 50 years into the future. Coliban Water is required to consider the social, environmental and economic costs and benefits and the actions needed to address population growth, nonresidential demand for water and potential climate variability. The Coliban System The Coliban system supplies an estimated residential population of 110,237 in Northern towns of Bendigo, Heathcote, Raywood, Sebastian and Tooborac and in Southern towns of Castlemaine, Kyneton, Elphinstone, Taradale, Maldon, Malmsbury, Newstead, Tylden and Harcourt. There are 52,632 customer connections; 92% are residential and 8% are non-residential. The system also supplies 1,682 rural licence customers with entitlements of 14,677 ML. Raw water is drawn from the Coliban storages of Upper Coliban, Lauriston and Malmsbury Reservoirs to supply the Coliban Southern and Northern systems. The Coliban Northern system also draws water from Lake Eppalock, in the Campaspe system, and from the Goulburn system via the Goldfields Superpipe. Coliban Water has the right to the inflow to the Coliban storages and 18% of the inflow to Lake Eppalock. A Bulk Water Entitlement of 50,260 ML applies to the raw water drawn from the Coliban storages and Lake Eppalock to supply both the urban and rural sectors. The Coliban Northern system also has 25,567 ML of Goulburn water shares and 2,729 ML of Campaspe water shares. Up to 4,000 ML of recycled water is also available from the Bendigo Water Reclamation Plant and Recycled Water Factory for non-potable use. Water Treatment Plants are located at Bendigo, Heathcote, Raywood, Castlemaine and Kyneton. All towns receive a treated water supply that complies with the water quality standards specified in the Safe Drinking Water Act Recent Experience Inflows to the Coliban storages and Lake Eppalock declined dramatically from 2002 with contents of less than 20% of capacity for more than 200 weeks and a low of 6% of capacity in June-July of Inflow to the Coliban storages in 2006/07 was less than 3,000 ML and only 5% of the historical average inflow of 62,000 ML. Up until September 2007, all towns in the Coliban system relied fully on inflows to the Coliban storages and Lake Eppalock. The Goldfields Superpipe was constructed in August 2007 and interconnected the Coliban Northern system with the Goulburn system. From August 2007 to late 2010, the Coliban Northern system was supplied almost exclusively with water pumped from the Goulburn system while the Coliban Southern system continued to be supplied from the depleted Coliban storages. The Coliban Southern system continues to rely on supply from the Coliban storages as there is no interconnection with Lake Eppalock and the Goulburn system. Water availability from the Goulburn system in the three years from 2007/08 resulted in allocations of 57%, 33% and 71%. To supplement supply from the Goulburn system, 33,902 ML of temporary water was purchased in those three years. Water restrictions were continually in force for more than eight years from October 2002 to January Stage 3 and Stage 4 restrictions were in force for most of that period. Page 4

5 Annual urban water demand ranged from 22,140 ML in 2001/02 (unrestricted year) to a minimum of 9,960 ML in 2006/07 (Stage 4 year). Permanent Water Saving Rules (PWSR) have been in place since January 2011 following the filling of the Coliban storages and Lake Eppalock. The current estimated PWSR annual raw water demand is 23,700 ML. The average annual residential consumption for the four years from 2007 to 2011 was 143 kl per property or marginally less than the regional average of 153 kl per property. The average annual non-residential consumption for the last four years was 756 kl per property or 12% less than the regional average of 855 kl per non-residential property. Supply to the rural sector was also restricted in the nine year since 2001/02 with allocations less than 100%. Zero allocations were provided in the three years of 2006/07, 2008/09 and 2009/10 but with an emergency supply made available to a limited number of rural customers. Annual rural water demands ranged from an estimated maximum of 17,800 ML in 2001/02 (100% allocation year) to a minimum of 2,500 ML in 2006/07 (emergency supply). The current estimated demand with a 100% rural allocation is 15,900 ML. Overall, the water requirements to meet PWSR demand in the urban sector, 100% allocation in the rural sector and operational water requirements is estimated at 39,600 ML per year. Level of Service The Water Supply-Demand Strategy is developed to achieve both: A PWSR supply reliability of 95% (where PWSR demand would be supplied in 95 out of 100 years and water restrictions would not be expected in more than 5 years in 100; and A desired restriction level of no worse than Stage 1. More severe restrictions, such as Stage 3, would only be expected if severe or unexpected water shortages occur. Supply and Demand Balance The available supply to the Coliban system is currently estimated at approximately 41,000 to 44,000 ML per year and is sufficient to meet the current system demand (PWSR raw water demand and 100% rural allocation) of 39,600 ML. However, the system demand is estimated to increase to 61,000 ML by year The increasing demand is primarily due to the forecast growth in residential population of 1.7% per annum. The rural demand is assumed not to grow. There are other factors that impact on demand but these will tend to offset each other. These factors include a potentially hotter and drier climate that is estimated to increase demand by 6% at year However, offsetting these two factors is the continuation of changes in customer consumption behaviour supported by community education and technology improvements. Customers have made a remarkable contribution to reducing water consumption across our region and trends indicate that customers continue to be very aware of their water consumption with an estimated reduction in household consumption of 10% over the next 50 years. The current annual available supply of 41,000 to 44,000 ML is estimated to decline marginally by year 2060 due to the potentially hotter and drier climate. The last 10 years has demonstrated that even in the driest of years Goulburn water can be purchased. The forecast supply includes 22,700 ML of water available on an annual basis from the Goulburn system (current limit of capacity of the Superpipe), 2,500 ML of Campaspe water and 2,500 ML of recycled water. The purchase of temporary water will be required in times of low water allocations in the Goulburn system to ensure the full 22,700 ML is available. The increasing demand and the declining supply will lead to a potential shortfall in supply. By 2030 and under median climate change conditions, the shortfall is estimated to be 4,000 to 5,000 ML associated with the Coliban southern system. By year 2030 the estimated shortfall is 19,000 ML to 25,000 ML. However a return to the dry conditions of the last 10 years would result in an estimated immediate shortfall of 7,000 ML increasing to 9,000 ML to 11,000 ML by Page 5

6 The evaporation at Lake Eppalock and the Coliban Headworks Storages is a significant draw on water resources and is taken into account in the determination of the water available from the headwork storages. Lake Eppalock also experiences poor water quality (blue-green algae and naturally occurring mangagese) which can limit the ability to take this water. Meeting Supply-Demand Shortfall Action is progressing to reduce water losses in the Coliban system. The implementation stage of the Rural Modernisation project is commencing in 2012/13 and will pipe open channels within the Harcourt rural system. The Rural Modernisation program will significantly reduce losses within the rural system estimated up to 6,000 ML when fully implemented. Rural buy-back of water entitlements could be an option for consideration by rural licence holders. However, the level of potential buy-back is unknown and will be better understood following implementation of the first stage of the rural modernisation program within the Harcourt system. Supply reliability is estimated to decline after year 2030 to a point where water restrictions would be necessary more frequently than the target of no more than 5 year in every 100 years. The connection of the Coliban Southern to the Coliban Northern system would enhance operational flexibility and enable water to be moved where it is most required and where it ensures the greatest supply reliability. Additional permanent water is also required. It is proposed to purchase water on the permanent Goulburn and Campaspe water markets, as required, over the period from 2030 to Permanent water shares are subject to annual allocation and are therefore not guaranteed to be fully available every year. The volume of additional shares to be purchased by year 2060 is estimated to be of the order of 20,000 ML. The movement of additional volumes of water from Lake Eppalock and the Goulburn system to Bendigo will require either augmentation of the Superpipe or extended access to water from the Waranga Channel beyond the normal irrigation season. The continuation of the main replacement and leakage reduction programs will provide water savings over the next 20 to 50 years. Further information regarding other possible alternative water supply considerations are contained in the Alternative Water Atlas. Proposed Actions Coliban System The proposed strategy to address the shortfall in supply over the next 50 years: Continue to manage in a proper and orderly manner development within Declared Water Supply Catchments to protect raw water supply through available planning and policy channels and funding initiatives; Implementation of the rural modernisation program to commence in 2012/13; Continue with the main replacement and leakage detection programs to minimise nonrevenue water; Continue to seek further opportunities for use of recycled water where it can regularly and reliably substitute for potable use; Use the temporary water market to address possible water shortfalls in the Coliban Northern system, Use the permanent water market to address possible water shortfalls in the Coliban Northern system, Consideration of a pipeline connection of the Coliban Southern system to the Coliban Northern system (Castlemaine Link) if required; and Increase Goldfields Superpipe transfer capacity by: o Extending the period of access to the Goulburn system, and/or o Augmenting the Goldfields Superpipe. Page 6

7 1. Introduction Coliban Region Water Corporation is a state owned water authority that provides water and wastewater services to a region with a population of 140,000 people, across 16,550 square kilometres of Central and Northern Victoria. The service area covers 49 towns in nine separate supply systems of which the Coliban Northern and Coliban Southern systems are two. The two systems are interconnected and share water from the Coliban Headworks Storages (CHS). Fully integrating the two systems may provide efficiencies and enhance supply reliability. The option of full integration is explored in this Water Supply Demand Strategy (WSDS). The Water Supply Demand Strategy identifies the best mix of measures to maintain a balance between the demand for water and the available supply in urban supply, and associated rural, systems, now and 50 years into the future. Coliban Water is required to consider the social, environmental and economic costs and benefits and the actions needed to address population growth, non-residential demand for water and potential climate variability. The development of Water Supply Demand Strategies is a requirement of water corporation s Statement of Obligations and are developed with close reference to the 2011 Guidelines for the Development of a Water Supply Demand Strategy (Version 2) issued by the Department of Sustainability and Environment. The supply-demand balance is tracked and reported on annually against the WSDSs and the WSDSs are thoroughly reviewed every five years. The development of WSDSs relies on many assumptions and estimates (including water availability, climate change, customer demands and growth) and the resultant recommendations are thus a guide to probable future needs, projects, capital investment and timing. It is therefore important to continually track and review performance on a regular basis and to also implement more serious drought response measures if and when required. Page 7

8 2. Overview 2.1. Key Features Towns Supplied The Coliban system supplies 14 towns and the Coliban Rural system. The Coliban Northern system supplies Bendigo, Heathcote, Raywood, Sebastian, Tooborac and rural customers. The Coliban Southern system supplies Castlemaine, Kyneton, Elphinstone, Taradale, Maldon, Malmsbury, Newstead, Tylden, Harcourt and rural customers. Customers 52,632 customer connections and an estimated residential population of 110,237 which is 78% of all regional connections and 81% of the estimated total residential population. The system supplies 1,682 rural licence customers with entitlements of 14,677 ML. The Coliban Northern system has 42,366 customer connections and an estimated residential population of 91,240 which is 63% of all regional connections and 67% of the estimated total residential population. The system supplies 877 rural licence customers. The Coliban Southern system has 10,266 customer connections and an estimated residential population of 18,997 which is 15% of all regional connections and 14% of the estimated total residential population. The system supplies 805 rural licence customers. Source of Water Raw water is drawn from the Coliban Headworks Storages (Upper Coliban, Lauriston and Malmsbury Reservoirs), Lake Eppalock (Campaspe system) and from the Goulburn system via the pumped Goldfields Superpipe pipeline supply from the Waranga Western Channel at Colbinabbin. The Coliban Headworks Storages supply the Coliban Southern system and also the Coliban Northern system by the 69 km long gravity Coliban Main Channel completed in The Lake Eppalock and Goulburn system supplies are pumped to the Coliban Northern system. The Coliban Southern system is not connected to these two additional sources of supply. Page 8

9 The Coliban Northern system has access to water from the Campaspe River system that comprises 18% of the inflow to Lake Eppalock, 2,597 ML high reliability (HR) water shares and 132 ML low reliability (LR) water shares. In the Goulburn system, the Coliban Northern system has access to 22,709 ML HL water shares and 2,858 ML LR water shares. Bendigo also has access to approximately 2,000 to 4,000 ML per year of recycled water for nonpotable use from the Bendigo Water Reclamation Plant and Bendigo Recycled Water Factory. A Bulk Water Entitlement of 50,260 ML applies to the raw water drawn from the Coliban Headworks Storages and Lake Eppalock. Coliban Water is the Storage Manager for the Coliban Headworks Storages whilst Goulburn-Murray Water is the Storage Manager for the Campaspe (Lake Eppalock) and Goulburn (Lake Eildon) systems. Coliban Water has a role to play as a referral authority in the proper and orderly implementation of Victoria Planning Provisions through Municipal Planning Schemes. Water Treatment Plants Bendigo, Heathcote, Raywood, Castlemaine and Kyneton; all towns receive a treated water supply. The Raywood system is being connected to Bendigo in 2012 and after connection treatment will no longer occur in Raywood How Water is Delivered to each Town Bendigo System Sandhurst Reservoir in Bendigo can receive raw water from three sources; the Coliban Headworks Storages via the Coliban Main Channel, and by pipeline from Lake Eppalock and the Waranga Western Channel. The water is treated at the Water Treatment Plant located at Sandhurst Reservoir (capacity 126 ML/day) and supplied to Bendigo and surrounding townships including Axedale, Strathfieldsaye, Huntly, Maiden Gully and Marong. The Bendigo Water Treatment Plant is a micro filtration plant. Heathcote-Tooborac System Raw water is pumped directly from Lake Eppalock or supplied from the Goldfields Superpipe and treated at the Heathcote Water Treatment Plant (capacity 6.5 ML/day). The treated water is then supplied to the townships of Heathcote and Tooborac. The Water Treatment Plant consists of clarification, sand filtration and disinfection. Raywood and Sebastian Raywood and Sebastian presently receive treated water carted from Bendigo. During 2012, these towns will be connected to Bendigo and will then form part of the Bendigo system. Castlemaine System Raw water is released from Malmsbury Reservoir and delivered by open channel and through the Poverty Gully Tunnel to McCay Reservoir at Castlemaine. The water is treated at the McCay Water Treatment Plant (capacity 18.4 ML/day) and supplied to Castlemaine, Elphinstone, Taradale, Maldon, Newstead, Harcourt, Guildford and Fryerstown. The Castlemaine Water Treatment Plant is a micro filtration plant. Kyneton System Raw water is pumped from the Lauriston Reservoir to the Kyneton Water Treatment Plant (capacity of 7 ML per day). The treated water is supplied to Kyneton, Malmsbury and Tylden. The Kyneton Water Treatment Plant is a micro filtration plant. Page 9

10 Rural System The Coliban Rural system is supplied by a network of 492 km of open channels with many dating back to the 1870s and 1880 s that receive a gravity supply released from Malmsbury Reservoir. The northern system can be supplemented with recycled water or with water from Lake Eppalock or the Goulburn system. The raw water is delivered to customer properties generally through separate channel outlets. The water is not for drinking nor can it be used for personal hygiene Customer Profile Of the 52,632 customer connections 92% or 48,334 are residential and 8% or 4,298 are nonresidential. The average annual residential consumption for the four years of was 143 kl per property which is marginally less than the regional average of 153 kl per property. The average annual non-residential consumption for the four years of was 756 kl per property or 12% less than the regional average of 856 kl per non-residential property. The largest five users are a Castlemaine Bacon factory (300 ML/year), a Bendigo Dairy manufacturer (250 to 300 ML/year), a Bendigo Poultry Processor (250 to 300 ML/year), the Bendigo Hospital (100 to 150 ML/year) and a Kyneton Meat Processing manufacturer (100 to 150 ML/year). Commercial customers account for 52% of the non-residential demand. Manufacturing accounts for 29% of the non-residential demand. Agriculture, forestry and mining account for the other 19% of non-residential demand. Table 1 shows the residential population and number of water connections for each town in the Coliban system. Table 1: Coliban System Population and Service Connections Town Service Connections 2011 Residential Total Residential Non residential Population 2011 Connections Connections Connections Axedale Bendigo Heathcote Raywood Sebastian Tooborac Coliban Northern sub total Castlemaine Elphinstone/Taradale Kyneton Maldon Malmsbury Newstead Tylden Coliban Southern sub total Coliban System Page 10

11 3. Recent Experience 3.1. Water Supply The main source of water to the Coliban system is inflow to the Coliban Headworks Storages and Lake Eppalock, located in the Campaspe River catchment. Coliban Water has the right to the inflow to the Coliban storages and 18% of the inflow to Lake Eppalock. The supply from these storages is under a Bulk Entitlement of 50,260 ML to supply both the Coliban urban and rural sectors. The Bulk Entitlement requires that a prescribed volume of environmental water be passed downstream of the Coliban Storages to the Coliban River. Additionally, the Coliban Northern system has access to 2,597 ML high reliability (HR) water shares and 132 ML low reliability (LR) water shares in the Campaspe system (Lake Eppalock). In August 2007 Coliban Water gained access to the Goulburn system with completion of the Goldfields Superpipe and has acquired 22,709 ML HL water shares and 2,858 ML LR water shares in the Goulburn system. The Goulburn water shares are 0.2% of the water entitlements supplied from the Goulburn River system. Bendigo has access to approximately 2,000 to 4,000 ML of recycled water per year for nonpotable use from the Bendigo Water Reclamation Plant and Recycled Water Factory. This water is used to supplement supply to the rural sector, public open spaces, school facilities and dual pipe residential systems. The Coliban Southern system relies on supply from the Coliban Headworks Storages; there is no interconnection with Lake Eppalock and the Goulburn system. The major headworks storages and service basins in the Coliban system have a combined capacity of 131,948 ML; Coliban storages (69,594 ML), Lake Eppalock share (54,837 ML), Sandhurst Reservoir (2,600 ML), Barkers Creek Reservoir (1,690 ML - rural water), Spring Gully Reservoir (1,680 ML - recycled / rural water), McCay Reservoir (1,360 ML) and Caledonia Reservoir (187 ML). The system storage capacity was reduced by 4% with the lowering of the Spring Gully Reservoir capacity by 800 ML in 2003 as part of dam rehabilitation works and the lowering of the Malmsbury Reservoir by 5,746 ML in 2009 while investigations take place into potential dam rehabilitation works. Average annual rainfall in the nine years from 2001 to 2010 was 82% of historical average rainfall and resulted in significant reductions to inflow to the Coliban storages and Lake Eppalock. Storage contents fell away dramatically with contents of less than 20% of capacity for more than four years (200 weeks) and a low of 6% of capacity in June and July of Up until September 2007, all towns in the Coliban system relied fully on inflows to the Coliban Headworks Storages and Lake Eppalock. The severe water shortage resulted in the Coliban System bulk entitlement being amended by Temporary Qualification of Rights in July 2007 with further amendments in June 2008, September 2009 and June Storage contents are shown in Figure 1. Very high inflows were received in 2010 with all storages filling by November 2010 with floods occurring downstream of Lake Eppalock in late 2010 and again in early Page 11

12 Water Held in Storage Coliban System 160, , ,000 Storage Contents ML 100,000 80,000 60,000 40,000 20,000 0 All_Coliban Storages Figure 1: Coliban system storage contents 1999 to 2011 Full Supply Volume Construction of the Goldfields Superpipe was completed in August 2007 that interconnected the Coliban Northern system with the Goulburn system. From August 2007 to late 2010, the Coliban Northern system was supplied almost exclusively with water pumped from the Goulburn system while the Coliban Southern system continued to be supplied from the critically low Coliban Headworks Storages. Water availability from the Goulburn system was limited in the three years from 2007/08 with allocations of 57%, 33% and 71%. To supplement supply from the Goulburn system, 33,902 ML of temporary water was purchased that consisted of volumes of 11,980ML, 14,922 ML and 7,000 ML purchased in 2007/08, 2008/09 and 2009/10 respectively. Carryover of 100% introduced in the Goulburn system in 2010/11 allowed unused water to be used in the next year and provided flexibility to manage supply reliability during this period of severe water shortage Raw Water Demand The complexities of the Coliban system and prevailing seasonal and operational conditions make demand for raw water extremely variable. There are two components of demand being the urban demand and rural demand: Urban Water Demand - comprises customer water consumption and losses incurred through leakage and pipeline bursts or from the use of fire hydrants and the flushing of mains to maintain general pipeline health. This demand also comprises evaporation at service basins, losses incurred in transfer of urban water in channels and pipelines and the operational water required to backwash and clean the treatment plant filters. Rural Water Demand - is the water used downstream of the Coliban storages and includes the water delivered to rural customers and channel water losses. The evaporation of water at our three major Coliban headworks storages and on our 18% share of Lake Eppalock is significant and is taken into account in the determination of the supply available from these storages. Annual evaporation loss at these major storages was estimated to be 13,170 ML in 2010/11. Page 12

13 3.3. Urban Water Demand The total urban system demand and water restriction levels over the last 10 years are shown in Figure 2. Annual Raw Water Demand megaliters Coliban System Annual System Demand Raw Water Demand Northern Raw Water Demand Southern Raw Water Demand Restriction Level Figure 2: Coliban System Urban Annual Demand and Water Restriction Levels Water restrictions commenced in October 2002 and were in force for the next eight years to January 2011 in the Bendigo and Kyneton systems and up until March 2011 in the Castlemaine system. Stage 3 and Stage 4 were in force for most of that period from March 2003 to September Annual water demand was a maximum of 25,490 ML in 2001/02 (unrestricted year) and a minimum of 11,820 ML in 2006/07 (Stage 4). The Coliban Northern system accounted for 78% of the total demand over the last 10 years. The low demand of 12,610 ML in 2010/11 was due to extremely high rainfall and with very little outside garden watering, together with the permanent water savings implemented by households. Table 2 shows the components of system demand over the last 10 years. Table 2: Components of Coliban Demand Component Total Percentage (%) Northern Percentage (%) Southern Percentage (%) Residential consumption 56% 59% 43% Non-Residential consumption 24% 23% 28% Operational Water 20% 18% 29% TOTAL 100% 100% 100% Water restrictions resulted in reductions in residential consumptions of up to 55% from a maximum demand of 14,152 ML in 2001/02 to a minimum of 6,316 ML in 2006/07. Water restrictions also had significant impact on non-residential consumption with reductions of up to 46% from a maximum demand of 5,560 ML in 2001/02 to a minimum of 2,990 ML in 2007/08 (Stage 4 year). The water required for operational needs and water loss is known as operational water and includes losses incurred through leakage and pipeline bursts or from the use of fire hydrants and the flushing of mains to maintain general pipeline health. It also comprises evaporation at service basins, losses incurred in transfer of urban water in channels and pipelines and the operational water required to backwash and clean the treatment plant filters. The amount of operational water ranged from 5,777 ML in 2001/02 to a minimum of 2,336 ML in 2006/07; it is generally about 20% of the total raw water demand. Page 13

14 The current town demands are shown in Figure 3 with Bendigo using 75% of the total urban system demand. Castlemaine is the major demand centre in the Coliban Southern system. Coliban System towns' proportion of Urban System Demand 75.2% 0.2% 2.6% 0.1% 0.1% 0.1% 12.3% 0.4% 5.8% 1.5% 0.7% 0.6% 0.3% Figure 3: Town raw water demand as a proportion of total urban system demand 3.4. Rural Water Demand Rural water demand comprises the water delivered to rural customers and the water losses incurred to transfer the water from the headworks storages through the open water channels. The estimated total rural water demand and water allocations over the last 11 years are shown in Figure 4. The Coliban Southern Rural system accounts for approximately 54% of the total rural demand although the Southern and Northern rural demands can vary significantly in any year. Annual Rural Raw Water Demand ML 20,000 18,000 16,000 14,000 12,000 10,000 8,000 6,000 4,000 2,000 0 Coliban System Annual Rural System Demand 2000/ / / / / / / / / / /11 Rural Delivery Rural Channel Loss Total Rural Demand Rural Allocation Figure 4: Coliban System Rural Annual Demand and Water Allocations 2000 to 2011 Annual rural water allocations of 100% were made in 2000/01 and 2001/02. Since then, until 2011/12, allocations have been less than 100%. Zero allocations were made in years 2006/07, 2008/09 and 2009/10; however, a supply was made available to a limited number of customers that met the criteria for an emergency supply (30% of licence volume) under a Qualification of Rights approved by the Minister for Water. These qualifications also allowed recycled water to be supplied in 2008/09 and 2009/10 (up to 40% of licence volume) to Northern rural channels that were commanded by the recycled water system and included the Ascot, Axe Creek and Cockatoo Hill rural channels. The limited rural supplies that were made available in 2006/07, 2008/09 and 2009/10 were equivalent to 15% to 25% rural allocations. 100% 90% 80% 70% 60% 50% 40% 30% 20% 10% 0% Allocation % Page 14

15 A 70% allocation was made in 2010/11 however the extremely high rainfall and wet conditions resulted in a low demand of 2,200 ML. Annual rural water demands ranged from an estimated maximum of 17,800 ML in 2001/02 (100% allocation year) to a minimum of 2,500 ML in 2006/07 (emergency supply to a limited number of customers). Over the last 10 years the rural deliveries accounted for 52% of the rural system demand while channel losses due to leakage and evaporation accounted for 48% of the rural system demand Total Raw Water Demand The total demand for raw water comprises the urban demand, rural deliveries and the operational water needs at service basins, water treatment plants and water distribution systems. System demand does not include evaporation at the major headwork storages of Lake Eppalock and the Coliban Headworks Storages; evaporation is taken into account when determining the supply available from these storages. The total demand for raw water ranged was a maximum of 43,300 ML in 2001/02 in a year of unrestricted urban supply and 100% rural allocation and associated high channel losses. The lowest total system demand was 14,360 ML in 2006/07 when Stage 4 water restrictions applied and there were limited rural supplies. The total demand for raw water is shown in Figure 5. During the last 10 years the urban consumption accounted for 49% of the raw water demand, rural deliveries accounted for 20% and losses accounted for the other 31% of all raw water demand. Coliban System Raw Water Demand Annual System Raw Water Demand megalitres 50,000 45,000 40,000 35,000 30,000 25,000 20,000 15,000 10,000 5,000 0 Total Coliban System Demand Total Coliban Northern Demand Total Coliban Southern Demand Figure 5: Coliban System Total Demand for Raw Water 2000 to Water Quality All towns receive a treated water supply. The treated water complies with the water quality standards specified in the Safe Drinking Water Act Page 15

16 3.7. Waterplan 2055 Review A review five years on of Coliban Water s last Water Supply Demand Strategy, Waterplan 2055, is available from Coliban Water s website. It outlines our progress against the measures which were detailed in the Waterplan 2055 to ensure long-term water security for our region. In the context of the long-term climate variability challenge, the review summaries our progress with each of the Waterplan 2055 initiatives under the following categories: Urban Savings Rural Savings Recycled Water use Sourcing Additional supply Other Projects Page 16

17 4. Levels of Service Coliban Water is committed to providing the systems and infrastructure to support needs of residential, business and industry customer s needs throughout our region. With the major investments made in supply infrastructure in central Victoria through the recent Millennium Drought of 2002 to 2010, significant additional works are not anticipated to be required in the Coliban Water region over the next 5-10 years to maintain the objective water security levels of service. However growth combined with weather variability and the potential for changes to our future climate may result in water shortages or drought and therefore the need for water restrictions. The Level of Service we aim to provide to customers has two components: 1. Reliability of Supply Coliban Water s objective is to provide sufficient water to meet customer demands of Permanent Water Saving Rules (PWSR) at 95% supply reliability. This means that PWSR would be in place 95 years out of every 100 years and water restrictions should not occur more often than the remaining 5 years out of every 100 years. 2. Maximum Restriction level (minimum water provision) Coliban Water s objective is that in those years where restrictions are necessary, we would try to keep restrictions to no worse than Stage 1. However in the event of severe or unexpected water shortages, restrictions may need to be more severe, such as Stage 3. Under the Victorian Government s 2011 Model Water Restriction Review, Stage 1 restrictions is, in the language of the review document, intended to provide an alert of an impending possible shortage and Stage 3 Restrictions would mean that just enough water is provided for use. Stage 3 restrictions includes no watering of lawn areas however garden areas may be watered within restricted hours on alternate days. Full details are available from the website. For the purposes of this analysis and reporting, the additional water needs (or supply shortfall) generally relates the additional water required to either achieve the target reliability of supply at PWSR and/or to enable restriction levels to be no worse than Stage 3. Even then these restrictions levels would only be expected a few years out of every hundred years. Under particularly severe or highly unexpected water shortage conditions, the Drought Response Plan would be triggered which could include emergency water supply measures and harsher restrictions. Occasionally, restrictions may also be required as a short-term management measure to deal with operational emergencies and incidents. Page 17

18 5. Climate Change / Variability Scenarios Central Victoria has a highly variable climate and there is no 'most likely' or 'most probable' future climate scenario. CSIRO modelling indicates that the extent and nature of climate change is unknown, so our water resource planning is built around a range of potential climate changes and potential water supply and demand futures. Based on DSE Guidelines and using CSIRO modelling, the WSDS considers five potential climate futures each with varying changes to temperature, rainfall and inflow to rivers and catchment storages. The five climate scenarios are: Scenario 1: Baseline climate. This scenario is based on a continuation of the historical climate, including rainfall and inflows, of the past 120 years from 1891 to Scenarios 2, 3 & 4: Change in future climate. This scenario set is based on a gradual increase in temperature of one degree (+1 o C) by approximately 2030 and two degree (+2 o C) by approximately The three scenarios under this set consider declining rainfall and inflow as a consequence of the increasing temperature being: Scenario 2: Wet (mild decline in rainfall and inflow); Scenario 3: Median (moderate decline in rainfall and inflow) and, Scenario 4: Dry (larger decline in rainfall and inflow). Scenario 5: Return to dry weather. This scenario is based on a return of the dry weather of 1997 to This scenario results in a greater and immediate reduction to available supply as well as an immediate increase in the demand for water. The changes to rainfall and runoff brought about by potential climate change and variability are shown in Table 3. Table 3: Climate Change Scenarios Scenario Change in Rainfall Change in Inflow Year 2030 Year 2060 Year 2030 Year 2060 S1 - Baseline climate 0% 0% 0% 0% S2 - Wet climate change -3% -5% -7% -13% S3 - Median climate change -7% -14% -16% -28% S4 - Dry climate change -7% -14% -27% -48% S5 - Return to dry weather -22% -22% -50% -50% Page 18

19 6. Demand Forecast 6.1. Current System Demand - Baseline Demand The system demand is comprised of the urban, rural and infrastructure demands as described below Urban System Water Demand Baseline Demand The baseline Coliban Urban System demand for each level of water restriction is based on a detailed analysis of the last 12 years of raw water use and customer consumption. Figure 6 shows the current baseline demand for PWSR is 23,700 ML per year. Coliban System Baseline Urban Demand Northern Southern Total PWSR Stage 1 Stage 2 Stage 3 Stage 4 Figure 6: Coliban Urban System annual baseline demand. Table 4 shows the forecast water savings with water restrictions. Table 4: Water Savings with Water Restrictions Restriction Level Approximate Saving (%) PWSR 0% Stage 1 6% Stage 2 28% Stage 3 38% Stage 4 50% 6.3. Rural System Water Demand Baseline Demand The baseline Coliban Rural System demand is based on the analysis of the last 11 years of rural raw water demand. The current baseline demand for 100% rural allocation is 15,900 ML per year; 7,370 ML in the Northern system and 8,530 ML in the Southern system. Allocations to the rural sector are reduced uniformly with water restrictions in the urban sector; for example, the introduction of urban Stage 1 water restrictions would align with a 70% allocation to the rural sector. Page 19

20 Figure 7 shows the rural demand with reduced allocations. Coliban Rural System Baseline Annual Demand Northern Southern Total Rural % 70% 55% 25% 10% Rural Allocation Figure 7: Coliban Rural System annual baseline demand. Table 5 shows the forecast water savings with reduced rural water allocations. Table 5: Rural Water Savings with Reduced Water Allocations Allocation Approximate Saving (%) 100% 0% 70% 14% 55% 24% 25% 57% 10% 83% 6.4. Current Total Raw Water Demand - Baseline Demand The current total raw water demand has been determined by the summation of the urban and rural baseline demands. The total demands are shown graphical in Figure 8. Coliban System Baseline Urban & Rural Demand Northern Southern Total PWSR & 100% Rural allocation Stage 1 & 70% Rural allocation Stage 2 & 55% Rural allocation Stage 3 & 25% Rural allocation Stage 4 & 0% Rural allocation Figure 8: Coliban System Total Raw Water annual baseline demand. Page 20

21 Table 6 shows the forecast water savings with water restrictions and reduced rural allocations. Table 6: Urban & Rural Water Savings with Restricted Supply Restriction Level Combined Approximate Saving (%) Northern Approximate Saving (%) Southern Approximate Saving (%) PWSR & 100% Rural allocation 0% 0% 0% Stage 1 & 70% Rural allocation 9% 9% 9% Stage 2 & 55% Rural allocation 27% 28% 24% Stage 3 & 25% Rural allocation 45% 45% 46% Stage 4 & Rural 10% allocation 69% 63% 80% 6.5. Future System Demand Future system demand had been determined by adjusting the baseline demand for population growth, future climate change and customer usage behaviour Population and Demand Growth Population growth has been determined based on reference to growth in connection numbers, the Victoria in Future (2008), census data and Local Government sources. The impact of growth on residential population and non-residential demand is considered separately as follows Residential Population Growth Residential population is forecast to grow in each town as shown in Table 7 with overall growth rate for the Coliban system being 1.7% per annum. Table 7: Coliban system forecast growth Adopted Growth Rate (% p.a.) Growth in Demand Coliban Northern Water Supply System Residential Agriculture, Forestry, Fishing & MiningManufacturing Commercial Total Growth Rate (% p.a.) Axedale 0.5% 0% 0.5% 0% 5% 9% 26% Bendigo 1.8% 0% 1.8% 2% 17% 34% 118% Heathcote 0.8% 0% 0.8% 1% 7% 14% 41% Raywood 0.5% 0% 0.5% 0% 5% 9% 27% Sebastian 0.5% 0% 0.5% 0% 5% 10% 27% Tooborac 0.0% 0% 0.0% 0% 0% 0% 0% Total Coliban Northern 1.8% 0% 1.8% 1.5% 16% 33% 114% Castlemaine 1.3% 0% 1.3% 1% 10% 20% 62% Elphinstone/Taradale 0.5% 0% 0.5% 0% 5% 9% 25% Kyneton 1.3% 0% 1.3% 1% 10% 19% 59% Maldon 0.9% 0% 0.9% 1% 8% 15% 45% Malmsbury 2.0% 0% 2.0% 2% 18% 36% 124% Newstead 0.8% 0% 0.8% 1% 7% 15% 43% Tylden 2.0% 0% 2.0% 2% 19% 39% 138% Total Coliban Southern 1.3% 0% 1.3% 1.0% 10% 20% 61% Coliban System 1.7% 0% 1.7% 1.4% 15% 30% 101% Page 21

22 The Macedon Ranges Shire Council (MRSC) has provided feedback around growth rates adopted for Kyneton, Malmsbury and Tylden based on work recently completed for their Macedon Ranges Settlement Strategy (MRSS). Whilst they consider the growth rate above for Kyneton is reasonable, they have advised that they consider the rates for Malmsbury and Tylden are high and they recommended rates of 0.8% and 1.1% respectively. The township areas encompassed by the MRSS and Coliban Water s service areas will not be the same with Coliban Water not servicing all the MRSS areas due to varying location and density of new development which in turn affect growth rates. The WSDS addresses water demand and supply availability at a system level not a town level and as such the higher figures of these smaller towns in Table 7 above have little impact on the overall system growth projections. Higher growth rates are slightly conservative and are carried through the analysis however Coliban Water acknowledges the valuable input from the MRSC which will also be considered and utilised when detailed water and/or sewer capacity augmentation investigations are undertaken at a township level Non-Residential Demand Growth In the last four years the non-residential consumption accounted for 29% of the Northern water consumption and 42% of the water consumption in the Southern system. Overall it accounted for 32% of the water consumption in the Coliban system. Table 8 shows the classification of non-residential customers; the commercial sector is forecast to grow at a rate of 1.7% per annum. The other non-residential sectors are forecast not to grow. Table 8: Classification of Non-residential Customers in the Coliban System Non-Residential Sector Northern Portion (%) Southern Portion (%) Combined Portion (%) Manufacturing-industrial 19% 57% 29% Commercial 56% 41% 52% Agriculture-forestry-fishing-mining 25% 2% 19% TOTAL 100% 100% 100% Total Growth in Residential and Non-residential Demand The growth in residential population combined with the growth in non-residential demand is forecast to increase the demand for raw water by 1.4% per annum. This will mean a 30% increase in demand by 2030 and a 101% increase by Table 7 shows the projected growth rates for the various customer sectors and the overall growth in demand over the next 50 years; the growth in demand is forecast to be greater in the Northern system with a 114% increase in demand by 2060 compared to the 61% growth in demand in the Southern system Environmental Demand The Coliban system Bulk Entitlement requires that water be passed downstream of the Coliban Headworks Storages to the Coliban River. The required passing flows are the lesser of the actual inflow to the Coliban storages or 8 ML per day; environmental releases of 8 ML per day amount to a maximum possible annual environmental obligation of 2,920 ML. The most recent amendment (Amendment Order 2012) to the Bulk Entitlement (Campaspe System Coliban Water) Conversion Order 1999 enables passing flows to be withheld and stored in an environmental reserve for later use enabling greater benefit to the environment with the same volume of water by adaptive management. Page 22

23 Climate Change Impact on Demand The analysis of the last 12 years of raw water data showed that urban demand increased with drier weather. Demands at year 2030 are forecast to increase with the reduced rainfall associated with climate change as shown in Table 9. The demands in the rural sector are forecast not to grow beyond the current baseline demand of 15,900 ML with a 100% allocation. Subject to final approvals, the first stage of the modernisation of the rural sector is proposed to proceed in 2012 with the modernisation of the Harcourt rural sector. Table 9: Impact of Climate Change on Rainfall and PWSR Demands Scenario Rainfall Decrease PWSR Demand Increase S2 - Wet climate change -3% 1% S3 - Median climate change -7% 3% S5 - Return to Dry -18% 8% Tables 10 shows the projected increase in urban demand due to climate change over the next years; climate change is forecast to add as much as 1,650 ML to the Northern demand and up to 370 ML to the Southern demand. Table 10: Climate Change Urban Demand Climate Scenario Year (ML) COLIBAN NORTHERN SYSTEM S1 - Baseline climate demand 18,350 18,350 (+0%) S2 - Wet climate change demand (3% and 5% less rainfall by 2030 & 2060 respectively) 18,350 (+0%) 18,610 (+1%) 18,350 (+0%) 18,780 (+2%) S3 - Median climate change demand (7% and 14% less rainfall by 2030 & 2060 respectively) 18,350 (+0%) 18,950 (+3%) 19,540 (+6%) S4 - Dry climate change demand (7% and 14% less rainfall by 2030 & 2060 respectively) 18,350 (+0%) 18,950 (+3%) 19,540 (+6%) S5 - Return to dry weather demand (immediate 20% reduction in rainfall) 20,000 (+9%) 20,000 (+9%) 20,000 (+9%) COLIBAN SOUTHERN SYSTEM S1 - Baseline climate demand 5,350 5,350 (+0%) 5,350 (+0%) S2 - Wet climate change demand (3% and 5% less rainfall by 2030 & 2060 respectively) 5,350 (+0%) 5,410 (+2%) 5,460 (+2%) S3 - Median climate change demand (7% and 14% less rainfall by 2030 & 2060 respectively) 5,350 (+0%) 5,530 (+4%) 5,720 (+7%) S4 - Dry climate change demand (7% and 14% less rainfall by 2030 & 2060 respectively) 5,350 (+0%) 5,530 (+4%) 5,720 (+7%) S5 - Return to dry weather demand (immediate 20% reduction in rainfall) 5,870 (+10%) 5,870 (+10%) 5,870 (+10%) Page 23

24 Behaviour Change There are a number of factors that will potentially change the way people use water over the next 50 years. These include Permanent Water Saving Rules, water pricing, grey-water reuse, changes to garden and lawn areas, education, and continuing technological and efficiency improvements in household appliances such as dishwashers and washing machines. The adoption of PWSR is forecast to reduce water demand by 15% to 20% compared to the unrestricted supply years of the late 1990s and early 2000s. This reduction has been factored into the forecast of the current baseline demand. In 2008/09 and 2009/10 the Coliban system demand was marginally less than expected as illustrated in Figure 2. The lower than expected demand could be due to a change in customer consumption behaviour and/or due to increased rainfall patterns. A clearer understanding of changing demand patterns will be evident over the next five to ten years. Customers have made a remarkable contribution to reducing water consumption across our region over the last 10 years and trends indicate that customers continue to be very aware of their water consumption. The full extent of reductions in demand due to greater voluntary conservation measures within the community is unknown. However, communities are generally much more careful in the way they use water and it has been assumed that average household demand will decline from the current estimated usage levels by a 10% over the next 50 years with continuing behavioural change, education and technological improvements. These assumed reductions in demand are due to permanent change to the way customers use water, resulting in a permanent reduction in water use that will most likely not bounce back. The eight years of water restrictions and the extremely wet year of 2010/11 reduced the raw water demand by up to 50%. This prolonged period of low water use is likely to see a continuation of suppressed demand for a number of years below the forecast system demands Improved Water Quality Any future improvement in treated water quality is forecast not to increase demand for water Summary of System Demand Impacts There are a number of influences that include population growth, climate change, behavioural change and water quality improvements that are forecast to either increase or decrease the demand for raw water over the next 20 to 50 years. These impacts are summarised as follows 1.5% and 1.0% per annum growth in population and non-residential demand for the Northern and Southern systems respectively; 6% to 7% increase with a Median climate change; 9% to 10% immediate increase with a return to dry weather conditions; 10% reduction in demand due to behavioural change, education and technology improvements; and Rural demand is not forecast to grow Table 11 shows by year 2030 the PWSR demand in the Northern and Southern systems is forecast to increase by 5,760 ML and 990 ML respectively. Page 24

25 Table 11: Forecast Future Urban System Demand Year (ML) Climate Scenario COLIBAN NORTHERN URBAN SYSTEM S1 - Baseline climate 18,350 23,360 34,300 S2 - Wet climate change demand 18,350 S3 - Median climate change demand 18,350 24,110 36,650 S4 - Dry climate change demand 18,350 24,110 36,650 S5 Return to dry weather 19,860 25,300 37,100 COLIBAN SOUTHERN URBAN SYSTEM S1 - Baseline climate 5,350 6,130 7,620 S2 - Wet climate change demand 5,350 S3 - Median climate change demand 5,350 6,340 8,150 S4 - Dry climate change demand 5,350 6,340 8,150 S5 Return to dry weather 5,830 6,690 8,320 Rural demand is not forecast to grow in the next 50 years above the baseline rural demand of 15,900 ML (100% rural allocation). Rural demand is generally split 7,370 ML in the Northern system and 8,530 ML in the Southern system. Modernisation of the rural sector commencing in 2012, may result in greater take-up of water entitlements and deliveries to rural properties, brought about in part by greater volumes of water trade, but this potential greater use would be offset by improvements in system efficiency and reduced losses. The total forecast system demand is the combination of the urban and rural demands. The forecast demands are shown in Table 12. The rural demand comprises 29% of the current Northern demand and this is forecast to reduce to 16% by the year The rural demand comprises 61% of the current Southern demand and is forecast to reduce to 51% by the year Table 12: Forecast Future Urban & Rural System Demand Climate Scenario Year (ML) COLIBAN NORTHERN URBAN & RURAL SYSTEM S1 - Baseline climate 25,720 30,680 41,570 S2 - Wet climate change demand 25,720 S3 - Median climate change demand 25,720 31,430 43,930 S4 - Dry climate change demand 25,720 31,430 43,930 S5 Return to dry weather 27,230 32,600 44,400 COLIBAN SOUTHERN URBAN & RURAL SYSTEM S1 - Baseline climate 13,880 14,630 16,100 S2 - Wet climate change demand 13,880 S3 - Median climate change demand 13,880 14,840 16,630 S4 - Dry climate change demand 13,880 14,840 16,630 S5 Return to dry weather 14,360 15,190 16,790 TOTAL COLIBAN URBAN & RURAL SYSTEM S1 - Baseline climate 39,600 45,310 57,610 S2 - Wet climate change demand 39,600 S3 - Median climate change demand 39,600 46,270 60,560 S4 - Dry climate change demand 39,600 46,270 60,560 S5 Return to dry weather 41,590 47,790 61,190 Page 25

26 Figure 9 shows the forecast urban and rural demand for the Coliban Northern system over the next 50 years; the dashed line is the forecast urban demand only. Figure 10 shows the forecast urban and rural demand for the Coliban Southern system over the next 50 years; the dashed line is the forecast urban demand only. Coliban Northern system Forecast Demand Forecast Demand megalitres per year Baseline Demand Urban & Rural Median Climate Change Demand Urban & Rural Return to Dry Demand Urban & Rural Baseline Demand Urban Return to Dry Demand Urban Figure 9: Forecast Coliban Northern demands Coliban Southern system Forecast Demand Forecast Demand megalitres per year Baseline Demand Urban & Rural Median Climate Change Demand Urban & Rural Return to Dry Demand Urban & Rural Baseline Demand Urban Return to Dry Demand Urban Figure 10: Forecast Coliban Southern demands Page 26

27 7. Supply Forecast The forecast supply is the average annual available supply (or amount of water) that is sustainably available each and every year whilst meeting target levels of service. Modelling, undertaken by the CSIRO and provided as part of the DSE WSDS Guidelines, forecasts the impact of the various potential climate scenarios on catchment run-off and the inflow to storages. REALM modelling, undertaken by PBJ & Associates Pty Ltd, provides forecasts of supply reliability and performance of the Coliban Northern and Coliban Southern systems under various demand, climate change conditions and operational arrangements. The estimated annual available supply for the Coliban Northern system is 30,000 ML to 32,000 ML comprised of: 22,700 ML from the Goulburn system via the Goldfields Superpipe; the volume of water that can be taken from the Goulburn system is only limited by the capacity of the Goldfields Superpipe as even in the driest of years in the last 10 years, Goulburn water was readily available 2,500 ML from the Campaspe system 2,000 ML of recycled water 3,000 ML to 5,000 ML from Lake Eppalock The available supply for the Coliban Southern system is based on the inflows to the Coliban Headworks Storages and is estimated to be approximately 11,5000 ML and declining to approximately 7,500 ML by year 2060 under a median climate change scenario. Forecast supply for the Coliban system is shown in Table 13. Table 13: Estimated Future Supply Climate Scenario Year (ML) COLIBAN NORTHERN SYSTEM S1 - Baseline climate 30,000 32,000 30,000 32,000 30,000 32,000 S3 - Median climate change 30,000 32,000 30,000 32,000 29,000 31,000 S5 - Return to dry weather 30,000 31,000 30,000 31,000 30,000 31,000 COLIBAN SOUTHERN SYSTEM S1 - Baseline climate 11,000-12,000 11,000-12,000 11,000-12,000 S3 - Median climate change 11,000-12,000 11,000-12,000 9,000 11,000 S5 - Return to dry weather 7,000 7,500 7,000 7,500 7,000 7, Headworks Storage Evaporation The major headworks storages of Lake Eppalock and the Coliban Headworks Storages incur significant loss of water through evaporation. This demand on water resources is influenced by seasonal and operational conditions - evaporation is most severe in the warmer months and varies significantly depending on the storage level surface area. The evaporation at Lake Eppalock and the Coliban Headworks Storages is a significant draw on water resources and is taken into account in the determination of the water available from the headwork storages. Lake Eppalock also experiences poor water quality (blue-green algae and naturally occurring mangagese) which can limit the ability to take this water. Annual evaporation loss ranged from an estimated maximum of 13,170 ML in 2010/11, when the storages were full, to a minimum of 2,100 ML in 2006/07 when the storages were near empty. The estimated major storage evaporation loss for the last 11 years is shown in Figure 11. Page 27

28 Coliban System Headworks Storages Evaporation Loss 14,000 Headworks Evaporation Loss ML 12,000 10,000 8,000 6,000 4,000 2, / / / / / / / / / / /11 Evaporation Headworks Figure 11: Coliban System Major Storage Evaporation Loss 2000 to Catchment Management Coliban Water is the land and catchment manager for the Coliban Headworks Storages catchments. The performance of these catchments in terms of runoff and yield can be varied by changes in the amounts and timing of rainfall as well as potentially by the level and type of development of the catchment. Coliban Water should continue to manage in a proper and orderly manner development within Declared Water Supply Catchments to protect raw water supply through available planning and policy channels and funding initiatives. These could include the likes of catchment protection guidelines, joint working with neighbouring water businesses and our local catchment management authorities, implementing State planning policy frameworks, participating in local planning policy reviews and the funding of catchment management programs. Page 28

29 8. System Performance Evaluation The following options have been assessed to determine the impact on system reliability: Demand Options o Revise restrictions policy Base Case (Stage 1-4 restrictions), maximum Stage 3 restrictions, maximum Stage 1 restrictions; o Reduce rural demand through rural system modernisation; o Reduce rural demand through buyback or rural water shares Supply Options o Reinstate the full capacity of Malmsbury Reservoir; o Purchase additional water from the Goulburn System; o Extend the Goldfields Superpipe to supply Castlemaine and Coliban Southern system rural demands. The arrangement of the Coliban system allows water to be transferred from the Coliban Headworks Storages to supply demand in the Coliban Northern system. However, there is no infrastructure to transfer water from Lake Eppalock to supply demands in the Coliban Southern System. As a result, the yield (or reliable supply) of the Coliban Southern system limits the reliability of the entire Coliban system Southern Coliban System To assess the maximum achievable supply reliability of the southern Coliban system, simulations were run assuming no water was transferred to the northern system via the Coliban Main Channel. Key Assumptions Southern urban and rural demands are supplied from the Coliban Headworks Storages only. Bendigo and Northern rural demands are supplied from Lake Eppalock and the Goulburn system via the Goldfields Superpipe. Restrictions are based on Coliban Headworks Storage levels Rural allocations match urban restrictions. Reliability is determined from annual restrictions. Impact of Climate Variability To assess the impact of climate change, the current configuration of the Coliban Southern system was assessed for the no climate change, +1 o C and +2 o C climate change scenarios. The Coliban Southern system has sufficient capacity to meet the 2030 demand under the +1 o C climate change scenario. Impact of Reduced Malmsbury Capacity The impact of the reduction of the storage capacity of Malmsbury Reservoir has an insignificant impact on the reliability of the Coliban Southern system or the minimum storage levels reached for the 2030 demand with no climate change. Maximum Stage 3 Restrictions Under the maximum Stage 3 restrictions option, the 2030 demands can be supplied under the +1 o C climate change scenario. However, under the +2 o C climate change scenario, despite being able to meet the required reliability in terms of the number of restrictions, the system fails as it runs out of water. Figure 12 shows the impact of Stage 3 maximum restrictions and the potential minimum level of Coliban Headworks Storages; under a 2 degree climate change the storages could empty at year Page 29

30 Figure 12: Coliban Southern system Impact of Stage 3 Maximum Restrictions Reduced Rural Demand A reduced rural demand was set with an approximate 44% reduction in the total rural demand in the Coliban Southern system. Simulation showed the system has sufficient capacity to meet the required reliability for the 2030 demand and +1 o C climate change scenario. Summary of Coliban Southern System Assessment of the Coliban Southern system shows that it can supply sufficient water to meet the forecast 2030 demands under the +1 o C climate change scenario with a maximum Stage 3 restrictions. A 44% reduction in rural demand would allow the system to meet the desired reliability for the maximum Stage 1 restrictions options under the o C scenario. Without this reduction, restriction levels beyond Stage 1 are required on occasions. However, by 2060 the Coliban storages either fail by running to empty or drop to extremely low levels when water restrictions are limited to no worse than Stage 3. In these circumstances more severe water restrictions, Stage 4, would be necessary in order to avoid the possibility of complete storage failure. The reduced capacity of Malmsbury Reservoir has a minor impact upon the reliability of the Coliban Southern system; however it does improve the minimum storage volumes, which may be important during periods of severe drought Coliban Northern System Pumping from Goulburn System Simulations were undertaken to determine a suitable trigger level at which pumping from the Goulburn system should commence; based on these simulations, an initial Goulburn Trigger level in Eppalock of 30GL was adopted. Revised Restrictions Policy The impact of revised restrictions policy on the volume of water pumped from the Goulburn system was assessed for the maximum Stage 3 and maximum Stage 1 restriction options by comparison with the base case scenario (Stage 1-4 restrictions). Under the base case option the Page 30

31 maximum annual diversion from the Goulburn system was limited to 22,706 ML, corresponding to the current number of high reliability water shares held by Coliban Water, and was unlimited under the other options to ensure this did not restrict the pumped volumes. Increases in pumped volume from the Goulburn system are required of up to 26% by the year 2030 when compared to the base case. Assumptions Coliban Northern system The following assumptions were made as part of this assessment: Northern urban and rural demands are supplied from Lake Eppalock and the Goulburn system via the Goldfields Superpipe; Trigger level for pumping from the Goulburn System based on a 30 GL storage level in Lake Eppalock; Transfers from the Goulburn system can only be made during the irrigation season (August 15 to May 15); Coliban Water can only access its share of the capacity of the Goldfield Superpipe; Restrictions are based on Coliban Headworks Storages levels and are uniform across the Coliban system; Rural allocations match urban restrictions; Reliability is determined from annual restrictions. Conclusions Coliban Northern system From the results of this assessment of the combined Coliban system it can be concluded that with additional Goldfields Superpipe capacity: A restriction policy with maximum Stage 1 restrictions can be achieved for the northern system; and, There would be additional costs for water purchase during extended drought periods. It should be noted that additional capacity in the Goldfields Superpipe may be available if Central Highlands Water are not transferring water and by pumping outside of the traditional irrigation season Combined Coliban System As the Coliban Southern system cannot be supplied from the Goldfields Superpipe, sufficient water must be retained in the Coliban Headworks Storages to supply the demands in the Coliban Southern system with the required reliability. This can be achieved by restricting transfers from the Southern to the Northern systems. Conclusions Coliban System From the results of this assessment of the combined Coliban system it can be concluded that: The Southern Coliban Trigger level needs to be set higher than 50 GL in order to achieve the required system reliability of 95%. Refer to Figure 13. Increasing the storage capacity of Malmsbury Reservoir from the currently restricted 67% back to 100% would result in the average annual availability of 2 GL (approximately) being available for transfer to the Northern Coliban system. Page 31

32 Figure 13: Coliban system Supply Reliability Extension of the Goldfields Superpipe to Castlemaine Simulation runs concluded that the pipeline extension does not significantly improve the reliability of the Coliban Southern system. Under certain operational conditions the Pipeline does improve supply security and allow the Coliban Headworks storages to be operated at a marginally lower level and thereby transfer up to a further 2,000 to 3,000 ML on average to the Northern system. The approximate shortfall in available supply over the next 50 years and the forecast supply reliability are shown in Table 14. Table 14 shows that a continuation of the baseline and median climate change climate conditions would result in high supply reliability with a low probability for the requirement for additional supplies over the next 20 years. With regard to the median climate change scenario, the supply reliability ay year 2030 is estimated to be at least 97% with a probability of water restrictions occurring three years in 100 years. This indicates that the shortfall in available supply is required infrequently and no more than three years in 100 years. Page 32

33 Table 14: Maximum Shortfall in the Supply-Demand Balance and Supply Reliability Year 2011 Year 2030 Year 2060 Climate Scenario Shortfall (ML) Supply Reliability Shortfall (ML) Supply Reliability Shortfall (ML) Supply Reliability COLIBAN NORTHERN SYSTEM S1 - Baseline climate Nil 100% Nil 99% 10,000 to 96% 11,000 S3 - Median climate change Nil 100% Nil 99% 13,000 to 15,000 94% S5 - Return to dry weather 10, % 2,000 to 3,000 COLIBAN SOUTHERN SYSTEM S1 - Baseline climate Nil 98% 3,000 to 4,000 S3 - Median climate change Nil 97% 4,000 to 5, % 13,000 to 15,000 98% 4,000 to 5,000 97% 6,000 to 7, % 97% 96% S5 - Return to dry weather 7, % 7, % 9, % to 8,000 to 8,000 to 10,000 Page 33

34 9. Demand Reduction Measures Coliban Water will continue to work with the community and pursue efficiency measures within the Coliban system to achieve demand reduction which can be permanent or temporary in nature. Demand reduction measures that provide on-going and continuous improvement to water reliability are described below Permanent Water Saving Rules (PWSR) PWSR were introduced by the Victorian Government in March 2005 and came into force following the lifting of water restrictions in the Coliban Northern system and the Kyneton system (part of the Coliban Southern system) in January 2011 and shortly after in the Castlemaine system in March The rules are designed to have customers permanently conserve water by requiring them to adopt some basic common sense water conservation measures. It is expected that PWSR will reduce 'unrestricted' demand, as experienced in the late 1990s, by 15% to 20%. An allowance of approximately 15% was factored into the assessment of the future Coliban system demand. The extent of actual water savings attributable to PWSR will be better understood with the evaluation of demand over the next four to five years Reduction of Operational Water Operational water is generally about 20% of the total raw water demand and has varied from 2,300 ML to a maximum of 5,800 ML. Typical annual losses are 4,000 ML comprising 1,200 ML required in the operation of the water treatment plants at Bendigo, Castlemaine and Kyneton, approximately 900 ML loss through evaporation at service basins, 700 ML channel loss in the transfer of water to service basins and 1,400 ML loss in urban distribution systems. To address water distribution losses, Coliban Water will continue its leakage reduction and water main replacement programs to replace old mains that are susceptible to bursts and leaks and adjusting pressures where this is appropriate and may assist. These programs are expected to save 10% of the distribution losses over the next 20 years. These estimated savings would amount to 150 ML in the Northern system and 40 ML in the Southern system. It is assumed that there are no savings in treatment plant process operational water or evaporation at major service basins Reduction of Rural System Losses Losses have been as much as 10,000 ML in years of 100% allocation (2000/01) to 1,200 ML in a year of emergency supply (2006/07). Channel re-lining works and operational improvements together with a lower take-up by customers of rural water has resulted in reductions in channel losses but are still significant and estimated to be between 6,000 ML and 7,000 ML when there is a 100% allocation of rural water. These losses are being addressed in the project for the modernisation of the rural sector. The first stage of the Rural Modernisation project is planned to commence in 2012/13 and involves piping open channels within the Harcourt rural system. Over the next 20 years, the rural modernisation project is estimated to provide estimated water savings of up to 6,000 ML. Some of these water savings may be offset by rural customers utilising more of their water allocations Water Saving Incentives and Community Education A number of water saving incentives and education programs have been in place during the last five years to achieve permanent behavioural change in community water consumption. Incentives and scheme have included the fitting of efficient water fixtures, such as low-flow shower roses and taps, in new dwellings and the water-efficiency labelling of water using appliances such as washing machines. Page 34

35 Other schemes have provided rebates for households and organisations involved in water smart programs such as the retro fitting of existing dwellings and the maintenance of efficient garden irrigation systems. These programs and other options such as grey-water re-use, installation of rain water tanks, continued improvement in the efficiency of appliances and fixtures are expected to continue to change the behaviour and volumes of community water consumption. A 10% reduction in demand spread over the next 50 years has been assumed in the water demand projections for these continued water efficiency savings Pricing Incentives Increases in the customer's water price can have an influence on reducing consumption. Price increases implemented over the last ten years may have influenced customer behaviour and thereby reduced overall demand. Similarly, any future price increases could be expected to further reduce demand. Any demand reductions that do occur are considered to be included as part of the 10% reduction in demand as outlined in the above Water Saving Incentives and Community Education programs Summary of Demand Reduction Measures Demand reduction measures that have not been considered elsewhere are estimated to save an additional 3,000 ML to 3,700 ML and comprise: Northern System: Up to 2,500 ML water saving in channel losses over the next 20 years with rural channel modernisation program; and 150 ML water saving with reductions in water distribution system losses over the next 20 years with main replacement and leakage reduction programs. Southern System: Up to 3,500 ML water saving in channel losses over the next 20 years with rural channel modernisation program; and 40 ML water saving with reductions in water distribution system losses over the next 20 years with main replacement and leakage reduction programs. Page 35

36 10. Additional Supply Measures Temporary Water Market The purchase of temporary water is an appropriate response if water shortages are likely to be infrequent. The Coliban Northern system has a forecast supply reliability of around 97% at year 2030 with water restrictions in three years out of 100 years. In these circumstances, for the next years, the purchase of temporary water is only required in those years when water restrictions are worse than Stage 3. This option is therefore likely to be a cost effective means to meet target levels of service. Some 34,000 ML of temporary water was purchased in the three year period from 2007 to 2010 and a return to similar dry conditions would result in the potential to purchase comparable volumes of temporary water. By 2030 and under median climate change conditions, the requirement for temporary water, for the Coliban Northern system, is estimated to be low. The need for temporary water is estimated to be necessary three years in 100 years. The provision of temporary water is not applicable to the Coliban Southern system Permanent Water Market The water market can be used to purchase permanent water entitlement to meet the supply shortfall. Permanent water entitlement is subject to annual allocation and is therefore not guaranteed to be fully available every year. The volume of permanent water entitlement to be purchased approximates to be about twice the volume of the supply shortfall in order to ensure that there is sufficient available water in most years. In the next 20 years the supply reliability is forecast to be at least 97% (no worse than Stage 3) for the baseline climate and median climate change scenarios which means that additional water is required in only 3% of years. Under these circumstances, the purchase of permanent water would be an inefficient use of water resources and not cost effective. However, supply reliability declines marginally after the year 2030 and the purchase of permanent water sources may then be appropriate. The volume of permanent water is estimated to be of the order of 2,000 ML to 5,000 ML at year 2030 and increasing to 20,000 ML to 25,000 ML by year A return to the dry conditions of 2002 to 2010 would accelerate the need for additional permanent water Connect Castlemaine to Bendigo This option would provide a pipeline connection from Bendigo to Castlemaine to provide greater water security to the Coliban Southern system in times of severe water shortage. However, this option does not provide additional water but rather allows for the distribution of the existing available water to where it is most needed Additional Use of Recycled Water Class A recycled water from the Bendigo Recycled Water Factory, located at the Bendigo Water Reclamation Plant, already provides for substitution of potable water by supplying to business, rural and residential customers on the northern side of Bendigo. Further opportunities should continue to be sought for use of recycled water where it can regularly and reliably substitute for potable use. Page 36

37 10.1. Additional Water Private Rain Water Tanks At present, recommendations from the Department of Health is that water for potable purposes should come from a reticulated potable supply where one is available rather than from rainwater tanks. Many households in the Coliban system most likely use rain-water tanks for non-potable purposes which effectively reduce the demand on the potable system. A restriction relating to rain water tanks is that they are reliant on local rainfall and shortages of tank water associated with low rainfall are highly likely to coincide with any shortage that may occur in the Murray River system. To be effective in significantly reducing potable demand, rainwater tanks have to be of a larger size and appropriately used. Tanks and plumbing associated with such systems are also expensive Alternative Water Sources An Alternative Water Atlas is being compiled that will identify and communicate potential sources of alternative water that may form part of the future supply-demand balance. The objectives of the Alternative Water Atlas from the Water Supply Demand Strategy Guidelines (DSE, 2011) are to: Identify the volumes of stormwater, recycled water and other alternative water sources available within the works of the Corporation (including wetlands and retardation basins) and/or local council; Help to inform future opportunities for the use of treated stormwater, recycled water and other alternative water sources in the control of either a water corporation or local council; Some of the alternative sources identified through the development of the Alternative Water Atlas are included in the assessment of options where a supply-demand shortfall exists. Page 37

38 11. Water Quality Measures The water treatment plants within the Coliban system are generally able to meet required customer water quality standards, even when the source water is of poorer quality than normal such as through the recent dry period. The Department of Health is also increasing the standards it expects for treated water quality including meeting a TDS (salinity) level of no more than 500 mg/l by The Coliban system WTPs may require some minor upgrades to achieve required water quality standards into the future. Page 38

39 12. Options Analysis Demand Reduction Demand reduction measures as listed in section 9 are in progress and have been taken into account in the forecast future demands. These include an estimated 10% reduction in household consumption spread over the next 50 years due to permanent changes in customer consumption behaviour and the implementation of future technologies Additional Water The water market can be used to purchase temporary and permanent water entitlement to meet the supply shortfall Options Summary The long list of options to address possible future water needs is attached as Appendix 2. Table 15 details those Coliban Northern system options that have been short-listed as the preferred options to meet future shortfall in demand over the next 20 years based on a consideration of the social, environmental and economic costs and benefits. Table 15: Water Supply Strategy Coliban Northern system Coliban Northern System Short List Options Strategy Source of Additional Water Item Project 9.2 Reduce Operational water Less than Additional Supply Demand Balance Benefit ML to 200 ML saving by Rural Modernisation Up to 2,500 ML savings when fully Total Additional Water i l d Other Projects if Required 10.1 Purchase Temporary Water 10.2 Purchase Permanent Entitlements Shortfall at Year 2030 Median Climate Change (ML) Implemented and Committed Projects Total Additional Water Up to 1,700 ML per Restriction Return to Dry (ML) Up to 1,700 ML per Restriction Only required in times of severe water shortage Project Summary Already Implemented Already Committed Project Status Ongoing; to maintain and improve system efficiency Improve rural efficiency by 50% or more by year 2030 Cost Benefit/ Cost (ML/$1m) Project Status < $ Preferred option. Purchased as and when required to avoid harsh restrictions As needed As needed < $2, Applicable in period 2030 to 2060, if required. 2,000+ 4,000+ Based on the above, the priorities for future additional supply to the Coliban Northern system, if required, would be: 1. Continue the main replacement and leak detection programs 2. Proceed with the Rural Modernisation project 3. Purchase Temporary Water, as needed 4. Purchase Permanent Water, as needed, generally beyond Page 39

40 Beyond the timeframe above, projects that may be required are to either extend the period of access to the Goulburn system and/or augment the Goldfields Superpipe. Table 16 details those Coliban Southern system options that have been short-listed. Table 16: Water Supply Strategy Coliban Southern system Coliban Southern System Short List Options Strategy Source of Additional Water Item Project 3,600 8,000 Implemented and Committed Projects 9.2 Reduce Operational water Additional Supply Demand Balance Benefit Up to 40 ML saving by Rural Modernisation Up to 3,500 ML savings when fully Total Additional Water 3,540 3,540 i l d Other Projects if Required 10.3 Connect Castlemaine to Bendigo Total Additional Water Shortfall at Year 2030 Median Climate Change (ML) Return to Dry (ML) Improve security against severe water restrictions Project Summary Already Implemented Already Committed Work to commence in Improve rural efficiency by 50% or more by year 2030 Cost Project Status Ongoing; to maintain and improve system efficiency Benefit/ Cost (ML/$1m) Project Status Preferred option to improve water security to Coliban Southern system Based on the above, the priorities for future additional supply to the Coliban Southern system, if required, would be: 1. Continue the main replacement and leak detection programs 2. Proceed with the Rural Modernisation project Page 40

41 13. Management of Risk and Uncertainty General The use of the water market to supplement supply is considered the lowest risk and cost option. Coliban Water s Coliban entitlement is approximately 0.5% of the total Goulburn system entitlement. The very relatively small volumes of water that we may be after should be able to be easily secured from this large market Murray Darling Basin Plan The Murray Darling Basin Authority has responsibility for developing the Murray Darling Basin Plan, which will guide the management of water resources across the Basin s four states and one territory. The Plan builds on and complements previous water reforms and contributes to the Authority s vision for a healthy working Basin. The Basin Plan aims to balance the water needs of the environment and other uses, through the establishment of new limits (known as sustainable diversion limits, or SDLs) on the volumes of water use in systems and regions. The draft Basin Plan identifies the following additional water needs to be recovered for southern catchments relevant to Coliban Water s systems: Wimmera-Avoca 23 GL Campaspe 12 GL Loddon 10 GL Murray 63 GL (This volume is expected to be met through NVIRP 2) Goulburn-Broken 99 GL (This volume is expected to be met through NVIRP 2) However, to meet the needs of the River Murray, a further 971 GL needs to be recovered. This volume would need to be recovered from somewhere within the southern Basin catchments that regularly flow into the Murray and there is flexibility as to where this water comes from. Coliban Water would likely only be affected by Basin Plan implications in the irregular times that it wishes to access the market to supplement low allocations or reservoir inflows. Due to the very small fraction of total system water that Coliban Water would be seeking, it is reasonable to assume that in all but the worst scenarios that there would be at least some water available. There is some risk relating to how much of the 971 GL may be sought from the smaller catchments upon which Coliban Water relies and what may happen if the proposed Murray- Darling Basin Authority voluntary buy-back process does not achieve the targeted volumes. From Coliban Water s perspective, the Campaspe and Loddon systems may be the catchments of greater concern to be more closely monitored into the future. Most of the aspects of the Basin Plan are presently not intended to take effect in Victoria until 2019 and as such there is time to monitor, contribute to and further assess the likely future impacts of the Basin Plan over coming years. Water Supply Demand Strategies are next due for renewal in 2017 which will be the appropriate time to incorporate any required changes. Page 41

42 14. Proposed Actions The WSDS proposes the following actions for the Loddon system Short-term Actions The actions proposed for the period covered by WaterPlan 3 (2013 to 2018) and WaterPlan 4 (2018 to 2023): Continue to manage in a proper and orderly manner development within Declared Water Supply Catchments to protect raw water supply through available planning and policy channels and funding initiatives; Implementation of the rural modernisation program to commence in 2012/13; Continue with the main replacement and leakage detection programs to minimise nonrevenue water; Continue to seek further opportunities for use of recycled water where it can regularly and reliably substitute for potable use; Use the temporary water market to address possible water shortfalls in the Coliban Northern system, and Consideration of a pipeline connection of the Coliban Southern system to the Coliban Northern system (Castlemaine Link) if required Long-term Actions The actions proposed for the period to 2060: Continue to manage in a proper and orderly manner development within Declared Water Supply Catchments to protect raw water supply through available planning and policy channels and funding initiatives; Continue with the main replacement and leakage detection programs to minimise nonrevenue water; Use the permanent and temporary water market to address possible water shortfalls in the Coliban Northern (and Southern) systems; Increase Goldfields Superpipe transfer capacity by: o Extending the period of access to the Goulburn system, and/or o Augmenting the Goldfields Superpipe; and Consideration of a pipeline connection of the Coliban Southern system to the Coliban Northern system (Castlemaine Link) if required. Page 42

43 15. Community & Stakeholder Engagement The Water Supply Demand Strategies are key strategies for a water business that guide the level of service to our customers and drive augmentation works to enable us to have available required supplies to meet demands. We recognise the importance of implementing a community engagement program that: Inspires confidence in the process and our ability to manage water resources now and into the future; Promotes acceptance and understanding of our plans; and Provides information that supports communities understanding and ability to have informed input. Some of the methods that have been utilised in engagement around the development and finalisation of this WSDS, or have fed into the WSDS, were: 2009 region wide Understanding our residential customer research project. This included focus groups and mail survey with willingness to pay a key focus; 2011 surveys sent to all 66,000 residential customers and 5,000 non-residential customers; Attended and presented to community groups upon request; Held public meetings in the Loddon system which had been particularly heavily impacted through the drought; Meetings with individuals and groups who came forward offering suggestions and comments relating to particular systems and towns; Website posting of a five year progress review of WaterPlan 2055 (Coliban Water s 2005 WSDS); Website posting of draft strategies requesting comments and feedback; Direct mail to almost 100 key stakeholders directing them to the website and requesting comments and feedback; Sending out hardcopies of the WSDS draft reports upon request; Presentations to Coliban Water staff of draft strategies requesting comments and feedback; and Presentations and strategy sessions with the Coliban Water Board leading up to WSDS endorsement. The feedback received and conversations had have been useful in informing development and in finalisation of our WSDS. There have been no major issues or suggestions raised significantly affecting the outcomes and recommendations of the WSDS with feedback received suggesting a high level of support for the direction proposed by Coliban Water and articulated through the strategies. Page 43

44 APPENDIX 1 Alternative Water Atlas Coliban System Summary Page 44

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