Sub-regional Total Water Cycle Management Plans for South East Queensland

Transcription

1 Sub-regional Total Water Cycle Management Plans for South East Queensland Patricia Hurikino Department of Energy and Water Supply Sanja Oldridge Sprout Water Management

2 Framework - Sub-regional TWCM Plans Principles Natural cycles minimising the alteration to natural flow and water quality Sustainable limits ensuring that the volume of water extracted from a source is sustainable for the community and environment Demand management reducing demand by minimising water use and losses and maximising efficient use/reuse Diversity in new supplies considering all potential sources Water quality managing water cycle to preserve water quality

3 Sub-regional TWCM Plans Project Developed 2 key development areas of: Ripley Valley 4,680 ha area 5km SE of Ipswich CBD Palmview and Caloundra South 926 ha and 2,310 ha south of Caloundra. Approach Stakeholder involvement - brought along the journey Systematic and transparent approach identify constraints and opportunities Project specific MCA Financial analysis - selection criteria project specific to identify preferred option Pathways for implementation identified

4 Methodology

5 Step 2: Technical assessment

6 Step 3: Develop options

7 Methodology

8 Results Robust planning process - can be used for future plans to inform water service infrastructure needs in other catchments The plans nominated water supply option with the capacity to supplement conventional supply at least overall cost investigated issues that have potential to impact on future water supply planning e.g. water quality upstream of a potable water supply

9 Research support During the development of the Sub-regional TWCM plans linkages to the program and research was undertaken through the Urban Water Security Research Alliance. The Alliance explored and expanded on the scope and effectiveness of the assessment methods. A number of applications were investigated resulting in some promising developments - such as Ipswich average end-use consumption (ie Beal et al. 2010) adopted as an estimate of water demand for different end uses, and to allocate water supply quantities. The work and can be accessed through the Urban Water Security Research Alliance website ( Beal, C., Stewart, R., Huang, T South East Queensland Residential End Use Study: Baseline Results Winter 2010 Urban Water Security Research Alliance Technical Report No. 31

10 Case study Ripley Valley Urban Development Area Year 2015 (0 4 years) 2021 (5 10 years) 2057 (Ultimate) Dwellings developed 2,375 9,000 50,000

11 Stakeholder consultation Workshop Purpose Inaugural workshop Identify the broader stakeholder group to be engaged Confirm or identify previous and existing planning processes for the study area Present an overview of the vision and goals for the project Confirm and define significant TWCM drivers for action Introduce the program and agenda for future Planning Workshops with the Advisory Group and consultation with the wider stakeholder group Confirm or identify information requirements 1 st Options workshop Provide background information required to select eight portfolios of water supply options for further assessment in consultation with Advisory Group. 2 nd Options workshop Identify eight water supply options (based on the technical assessment outlined in the briefing paper) for further assessment Identify selection criteria for MCA and financial assessments Multi Criteria Analysis workshop Cost Benefit Analysis workshop Implementation Pathways discussions Carry out the Multi Criteria Analysis to identify three water supply options for the Ripley Valley development area. Discuss probability percentages with STAG to verify the most likely overall cost outcome for each option Identify of the most suitable water supply option Identify the most appropriate implementation pathway (ie who will lead the next step of investigation, and who is responsible in their jurisdiction to take it further)

12 Summary of Advisory Group drivers Cost affordability and financial viability Environmental the effects of rapid development on environmental values Water water security and stormwater management water security and stormwater management Community community wellbeing and outcomes optimisation Flood hazard management minimising developmental impacts Timeline balance and prioritisation TWCMP implementation realising practical results Climate change variability/uncertainty long and short term

13 Considerations Climate change: CSIRO and Australian Greenhouse Office implications for water supply systems Environmental: Essential Habitats and Essential Regrowth Habitats Regional Ecosystems High Value Regrowth Vegetation Koala Habitat Value Data Queensland Heritage Register Wetland Management Area Protected Areas of Queensland Acid Sulfate Soils EPBC Act Protected Matters Report Water Quality Bremer River environmental values and water quality objectives

14 Considerations Relevant planning policy documents

15 Water consumption targets SEQ Regional Plan Residential consumption target will be 230 litres or less per person per day on average across the region Efficient water use must be considered as part of planning new communities and designing new buildings Water sensitive urban design options to achieve the targets include internally connected rainwater tanks, communal rainwater tanks, stormwater harvesting, and dual-reticulation recycled water systems Queensland Development Code (QDC) Class 1 buildings connected to a reticulated town water supply system provided by a water service provider registered under the Water Act 2000 has a minimum storage (ie water reuse) capacity: Water savings targets of 70 kl per year for new detached houses and 42 kl per year for other new Class 1 dwellings apply in Ipswich City Council

16 Water quality management Current water distribution regulatory requirements (ie Water Supply (Safety and Reliability) Act 2008 ) stipulate the water quality risk management approach for the following: Recycled Water Management Plan required under the Water Supply (Safety and Reliability) Act 2008 enables operation and management of water quality for the dual reticulation schemes in Queensland Drinking Water Quality Management Plan required under the Water Supply (Safety and Reliability) Act 2008 enables operation and management of water quality for the water supply schemes in Queensland, including stormwater harvesting for potable use

17 Water demand estimates Undertake breakdown of the various land use categories within the developments Undertake further breakdown of each land use category within the developments Convert the above components into equivalent persons (EPs) Calculate the ultimate water demands based on EPs and desired standards of service (DSS) for the development, expressed as L/s Calculate water demands based on the ULDA population projections (by applying the DSS to the population projections) and tabulated for comparison against the ultimate land use-based demands Water demands EP Average Daily Demand (L/s) Average Daily Demand (ML/d) Ultimate Demands 130, The ultimate demands for the Ripley Valley can be expressed as the following average demands for the whole of the development: 552 L/ET/day or 230 L/EP/day

18 Potential water supply sources Current potable water supply Southern Regional Water Pipeline (SRWP) considered an ultimate off take flow for the Ripley Valley of 59.5 ML/d under peak month conditions (44.0 ML/d average) Sufficient capacity in the SRWP to meet the projected bulk water demands The SRWP as designed can satisfy water demand from the Ripley Valley UDA (at 2031), for all potable and non-potable uses Roofwater harvesting Demands met Volume of reuse per year Land use (%) (kl/ha) Industrial 92 1,007 Public Services 62 1,188 Residential Town Centre City Fringe Rural Residential

19 Potential water supply sources Stormwater harvesting Catchment 60% reliability 80% reliability Area (ha) Annual demand Storage area Volume kl Storage area m 2 m 2 Volume 1 3, ,196 8, , , , ,043 10, , ,358 3 n/a n/a n/a n/a n/a n/a , , ,353 5 n/a n/a n/a n/a n/a n/a 6 1,900 67,129 4,200 88, , ,500 67,853 6,500 89, , , ,786 30, , ,510 9 n/a n/a n/a n/a n/a n/a 10 11, ,674 37, , , , ,958 65, , , , ,059 35, , , , , , , , , ,052 19, , , , , , , , , , , , , , , , , , ,000 57,946 20,000 76, ,265 kl kl

20 Potential water supply sources Groundwater The Ripley Road sandstone aquifer on the north eastern side of the project area seems to be a possible source for groundwater exploitation although in general the groundwater seems to be of poor quality across the project area Recycled water An indicative percentage of 35% (ie of the total water demand) is assigned for the recycled water supply Purified Recycled Water The Western Corridor Recycled Water Project (WCRWP) has the ability to supply a total of 185 ML/day of Purified Recycled Water, some of which can be used within the Ripley Valley development area

21 Water supply and demand summary The Ipswich average end-use consumption (ie Beal et al. 2010) was adopted as an estimate of water demand for different end uses, and to allocate water supply quantities. End-use Water demand Available water supply sources (L/p/day) Rainwater tanks Stormwater Recycled water Current harvesting o potable Indoor potable demand Indoor nonpotable demand Outdoor nonpotable demand o potential potable sourced if treated to potable water standard supply to meet the demand Beal, C., Stewart, R., Huang, T South East Queensland Residential End Use Study: Baseline Results Winter 2010 Urban Water Security Research Alliance Technical Report No. 31

22 Water supply options Nominated by Advisory Group Options End-use Descriptions 1. Conventional water supply incl. roofwater Roofwater to supply toilet and lot irrigation. Potable water source for the rest (ie bathtub, tap, dishwasher, shower and clothes washer). Conventional water supply (incl. building code requirement via lot based roofwater harvesting - rainwater tanks) 2. Conventional supply (incl. roofwater) + stormwater harvesting (eg open space irrigation, streetscapes) 3. Conventional supply (excl. roofwater) + supplementing with stormwater harvesting to homes and open space 4. Conventional supply (incl. roofwater) + purified recycled water (PRW) for nondomestic commercial uses 5. Conventional supply (incl. roofwater) + purified recycled water for public open space irrigation 6. Conventional supply (incl. roofwater) + purified recycled water for public open space irrigation and lot irrigation. 7. Conventional supply (excl. roofwater) + locally treated wastewater to Class A+ (dual reticulation) to homes and open space for irrigation and non-potable use 8. Conventional supply (incl. roofwater) + locally treated wastewater to Class A+ (dual reticulation) for open space irrigation and remainder of available water for Irrigation of ha on Swanbank. Roofwater to supply toilet and lot irrigation. Potable water the rest (ie bathtub, tap, dishwasher, shower and clothes washer) + opportunity to harvest and supply water for open space irrigation. Potable water supply for all end-uses + opportunity to harvest and supply water for open space irrigation. Roofwater to supply toilet and lot irrigation. Potable water source for the rest (ie bathtub, tap, dishwasher, shower and clothes washer) + PRW for commercial aircon units and commercial gardens. Roofwater to supply toilet and lot irrigation. Potable water source for the rest (ie bathtub, tap, dishwasher, shower and clothes washer) + PRW for open space irrigation Roofwater to supply toilet. Potable water source for the rest (ie bathtub, tap, dishwasher, shower and clothes washer) + PRW for open space irrigation and lot irrigation. Recycled water (Class A+) to supply toilet, and lot and open space irrigation. Potable water source for the rest (ie bathtub, tap, dishwasher, shower and clothes washer) Roofwater to supply toilet and lot irrigation. Potable water source for the rest (ie bathtub, tap, dishwasher, shower and clothes washer). Recycled water (Class A+) to supply open space irrigation and irrigation of ha on Swanbank. Option 1 + stormwater harvesting Conventional water supply (incl. building code requirement via stormwater harvesting to homes and open space) Option 1 + PRW for commercial aircon units and commercial gardens. Option 1 + PRW open space irrigation. Option 1 (excluding lot irrigation) + PRW for open space and lot irrigation. Dual reticulation scheme (incl. building code requirement via recycled water Class A + reuse) Option 1 + Class A + treated effluent for non-residential irrigation

23 Selection criteria Nominated by Advisory Group Objective Criteria Measures Quantitative & Qualitative Technical Flexible to staging Adaptable to technological change Reliability of water supply Practicality of operation Optimised usage of potable water supplies Spatial layout of infrastructure and development Linear network vs grid network LOS, redundancy, system components capable of operating in varying combinations ULDA targets are met Systems simple to operate and capable of operation of sufficient regularity to maintain water quality Potable water only used for potable uses as much as possible Environmental Micro climate controls-heat Challenge of dispersive soils Environmental compliance (legislative) and licence requirements Carbon footprint Achieving the SPP water quality requirements SPP Healthy Waters Water supply quality Ability to meet license requirements and practicality of maintaining licenses (eg decentralised treatment) Carbon footprint of operation (ie include treatment, transportation, chemical transport, waste removal etc) Social/ Community Community benefit of green spaces Affordable housing UQ study of long term sustainability in Ripley Valley (potential measures) Social acceptability willingness to pay/using recycled water Simplicity of system for use Appropriate location of infrastructure with respect to residents and community facilities Noise, odour, vehicular traffic, lighting and surrounding land use impacts from infrastructure

24 Selection criteria Nominated by Advisory Group Objective Criteria Measures Quantitative & Qualitative Health & Safety Green spaces value of trees to reduce respiratory illness Disease and pest control eg: mosquitos External benchmarking to socio economic Level of impact from transport, storage and application of chemicals on-site in treatment process Economic Water quality Compliance with state policies/guidelines (drinking and recycled water, SPP) National guidelines (stormwater harvesting) Micro climate controls-heat Use of chemicals in treatment Waste product disposal Timing and staging of appropriate works (efficiency of network rollout) Water affordability to consumers Cost benefit analysis (triple bottom line) Consistency of income stream/return to investment Alternative water supply for any proposed area needs to be on a commercially viable basis (revenue) Level of impact from storage, transport and disposal of waste materials from treatment process Operating costs Capital costs Prudency and efficiency Levelised costs Climate Change Resilience Risk Scale of communal solutions vs risk to Council Asset handover (Queensland Urban Utilities/Ipswich City Council) Commercial imperative Practicality of ownership/governance/interactions between parties

25 Multi Criteria analysis Multi Criteria Analysis (MCA) is a process for weighing up alternative options or actions against each other, in order to arrive at the best alternative. Range of scoring are as follows: Description Score Against objective -5 Fails objective -2 Does not apply 0 Partially satisfies objective 1 Meets objective 2 Exceeds objective 3 STAG identified the shortlisted options as follows: Option 1 Conventional water supply including roofwater (ie business as usual option) Option 5 Conventional supply (including roofwater) + purified recycled water for public open space irrigation Option 2 Conventional supply (including roofwater) + stormwater harvesting (eg open space irrigation, streetscapes)

26 Financial assessment High level cost estimates were carried out in relation to a set of confirmed selection criteria. Some were developed in a workshop environment and others generated in-house for scrutiny by the Advisory Group. Tasks: Collate and prepare background information Adapt financial assessment selection criteria Develop spreadsheets including costing of each selection criteria allocated to cost adverse or benefit, and associated probabilities to come up with the most likely overall cost outcome for each option Discuss probability percentages with STAG to verify the most likely overall cost outcome for each option Identify of the most suitable water supply option Financial assessment criteria Economic Lifestyle benefit Water quality Captured in Environmental and climate change Climate change impact Community expectation Security of adequate supply Efficiency of operation Ownership issues/risk Legislative requirements

27 Project outcome Ranking Water supply option Most likely overall cost outcome 1 Conventional supply (incl. roofwater) + purified recycled water for public open $952,110,942 space irrigation 2 Conventional water supply incl. roofwater $1,026,872,479 3 Conventional supply (incl. roofwater) + stormwater harvesting (eg open space irrigation, streetscapes) $1,045,667,881 The preferred water supply option for Ripley Valley a hybrid of two water supply options: Conventional supply (including roofwater) for residential use to QDC standard Combination of purified recycled water (PRW) for public open space irrigation and commercial use + stormwater harvesting (eg open space irrigation, streetscapes) The implementation pathway assessment identified the following: The ULDA will take a lead role in adapting the SR TWCMP recommendations to feed into a broader TWCM context The SR TWCMP may be subject to changes based on review and investigation from further work in a TWCM context

28 Thank you for your attention.