SEGRA th National Conference, Townsville, QLD. Associate Professor Peter Waterman Dean Barr

Transcription

1 An Assessment Framework for Regional Australia SEGRA th National Conference, Townsville, QLD Associate Professor Peter Waterman Dean Barr

2 Decentralised Water Supply? Traditional centralised infrastructure Dams Desalination plants Sewage treatment plants Waste water recycling plants Decentralised water infrastructure Household rainwater tanks Community/Sub-community rainwater tanks Stormwater harvesting Community roofwater harvesting Community water mining and recycling

3 Australian examples Payne Road, The Gap, Brisbane (22 lots) Household tanks connected to community tanks Filtered and UV sterilised Use of grey water for irrigation Anticipated reduction of mains water use by 60% Warrnambool, Victoria (142 lots) Roofwater harvesting, piped to local reservoir 76% demand reduction expected Coomera, Gold Coast (46,000 houses) District waste water recycling, redistributed for toilet, laundry and external use Household rainwater tanks Homebush Bay, Sydney (2,000 houses) Water mining Toilet flush, laundry and outdoor use 50% reduction on mains water demand

4 Case study: Ridges at Peregian Springs, Sunshine Coast, QLD University of the Sunshine Coast - Sustainability Assessment Commissioned by Sunshine Coast Regional Council Aim: Develop an assessment framework for decentralised water provision usable at local and regional scales. Triple Bottom Line investigation of sustainability Ridges at Peregian Springs as a case study

5 Ridges at Peregian Springs Ridges at Peregian Springs

6 Proposed decentralised system New housing estate of approx. 1,000 dwellings Roofwater harvesting PW supply Sub-community storage tanks Nearby 10 ML reservoir Water mining of sewage trunk Toilet flushing, laundry, external Hybridised with mains water supply and sewage system

7 Roofwater harvesting Rain water collected from roof tops Sub-catchment Storage Tanks Treated Water Storage Mains supply Ridges at Peregian Springs Ridges at Peregian Springs Treatment Plant Peregian Springs

8 Water mining 143 ML/a (A+ Quality) TREATMENT FACILITY Sewer trunk mine RIDGES AT PEREGIAN SPRINGS 180 ML/a (typical sewage water) Treatment waste 37 ML/a (typical sewage water quality + treatment waste) COOLUM STP Discharged to water quality standards COOLUM CREEK

9 Developing an assessment framework Adopted the concept of CCAUD Climate Change Adaptive Urban Development Justin Holbrook of SUDTEC development company. SUDTEC Sustainable Urban Development and Technology

10 CCAUD application of climate proofing additionality in infrastructure sizing diversification of supply sources diversification of demand sources co-location at the demand point of water services infrastructure renewable energy production biodiversity-friendly carbon sinks delivery sourced from local/regional expertise and labour

11 Explored established frameworks Triple Bottom Line (TBL) Biophysical (Environmental) Social Economic DPSIR Model Drivers, Pressures, State, Impact and Response DPSEEA Model Drivers, Pressures, State, Exposure, Effects & Action

12 Conceptual assessment framework IDENTIFY ISSUES CCAUD components Context Policies Sustainability outcomes SOCIAL Human health Urban amenity ECONOMIC Economic Analysis Costs of GHG emissions and water BIOPHYSICAL Climate Change Water supply & demand Wastewater & energy GHG emissions Receiving environment ANALYSIS TOOLS TBL, DPSIR, DPSEEA Life Cycle Analysis (LCA) Economic Tools (CBA, MCA) EVALUATION Synthesis Consultation Community Business Government RECOMMENDATIONS Policy & management Water provision Costs and pricing GHG & renewable energy Wastewater elements Social values Environmental impact & monitoring

13 Identify issues / scoping Drivers 68% Population growth on 2006 by 2031 on Sunshine Coast Changing climatic conditions 30% reduction in rainfall by 2070 No sites available for more dams (Traveston) Costly, high energy, unpopular desalination plants Policy SEQ Water Supply Strategy QLD Government ClimateSmart Adaptation Action Plan SCRC Climate Change Strategy National Water Initiative (COAG) Water for the Future Program (Cwlth)

14 Rainfall projections Sunshine Coast SimCLIM Baseline Annual Rainfall Sunshine Coast SimCLIM 2070 Annual Rainfall Sunshine Coast (worse case)

15 Comparison to CCAUD concept Climate proofing Climate risks considered Additionality in infrastructure sizing Maximise roof surface area, sub-level tanks Diversification of supply sources Mains supply and sewage hybridisation Roofwater harvesting for PW Water mining non-pw Diversification of demand sources Toilet flushing, laundry cold water, external use, drinking water Co-location of supply and treatment infrastructure Water storage, sterilisation and waste water plant in the estate Renewable energy Possible future inclusion Carbon sinks Landscaping in accordance with Planning Schemes Local and regional expertise and labour Support local industry, build experience in sustainable development technologies

16 Social Water security health risks nutritional higher food costs Respiratory dust psychological Regional communities Reduced public amenity Security of public amenity investments parks and gardens recreational areas Reduce risk of supply disruption Disaster risk reduction Ownership of infrastructure (private/public) Acceptability Recycling Water prices

17 Biophysical 50 mm p/a reduction since % rainfall reduction by 2070 Ridges reliant on mains during dry season, net export of water overall Life Cycle GHG emissions greater than mains supply - less than desalination Reduced runoff to receiving environment Reduced point source nutrient load on environment (potential increase of diffuse source needs to be investigated)

18 Economic Net export of water Investment in expansion of services is synchronised with growth of demand Initial assessment suggests cost of supply lower than desalination Fully comprehensive economic assessment is required, not just the direct cost of supply Social cost-benefit analysis Multi-criteria analysis Indirect costs and benefits e.g. value of eco-services of receiving environment, health

19 Recommendations Further consideration of decentralised systems justified Hybridisation with mains supply step towards autonomous systems Value of in-house climate change modelling Further investigation required of changes in diffuse/point source pollution mechanisms Economic analysis must include all direct and indirect costs and benefits for meaningful comparisons to assist in decision making Consider use of chemicals in water treatment in GHG emission calculations and impact of receiving STP and receiving environment

20 Conclusion Climate Change Population and settlement growth Energy provision and GHGs Regional water supply Regional waste water treatment BAU Hybridisation CCAUD Dams, Water Treatment Plants, Main Services Water Supply and Treatment Services WaterMining, Roofwater Harvesting, Storage and Treatment facilities Large scale investment in regional assets, new dams, desal plants Infrastructure Development Small scale decentralised asset investment Non conformity Centralised risk, increased load on assimilative capacity Emerging Policy Direction Receiving Environment Conforms with local, state & federal urban water reform attracting related funding Reduction of risk and pressure Vulnerability & insecurity Urban Water Amenity Security Secure and resilient urban amenity and reduced health risks Increased pressure & risk - Unsustainable Demand on Water Supply and Water Treatment Services Managed, planned, adaptive - Sustainable

21 Questions? Further information: Associate Professor Peter Waterman Faculty of Science, Health & Education Climate Change, Coasts and Catchments University of the Sunshine Coast