Optimal Water Resource Mix for Metropolitan Adelaide
Susan Cuddy, CSIRO
CSIRO, University of Adelaide, University of South Australia, AWQC, Flinders University, DEWNR
Water Resources Mix for Adelaide
In November 2012, the Goyder Institute for Water Research funded a research programme as a contribution to the building of a strong information base to inform debate on how best to underpin an efficient and sustainable water supply for metropolitan Adelaide, now and into the future, due to the likely impacts of a drying climate and population growth. Metropolitan Adelaide has multiple sources of water – surface water, groundwater, desalinated water, stormwater, roof or rain water, recycled water and the River Murray – that can be utilised and managed for supplying the city’s water needs. Using those sources in combination requires consideration of an appropriate balance across objectives such as supply security, economic cost, social preferences and environmental impacts. The research programme, project U2.2 within the Goyder Institute for Water Research’s urban water portfolio, was designed to explore these considerations through:
engaging with stakeholders to provide an effective communication pathway and an agreed basis for evaluating alternative water supply mixes
providing a model that simulates the supply, demand and stormwater and wastewater discharge dynamics of Metropolitan Adelaide water supply system
developing a multi-objective optimisation methodology to assess trade-offs
monitoring household water use to better predict demand
performing legal and governance analysis in delivering water solutions
conducting economic analysis of the direct and indirect costs of supplying water from the multiple sources
improving understanding of social values and preferences regarding water solutions.
The project team was drawn from researchers at the Universities of Adelaide and South Australia, Flinders University, CSIRO and SA Water, with contributions from EPA, the SA Departments of Environment, Water and Natural Resources; and Planning, and the Adelaide and Mt Lofty Ranges Natural Resources Management (AMLRNRMB). The project concluded in early 2014.
Progress Update and Key Findings
The water sources that are available to manage water supply in the Adelaide's metropolitan region include surface water, groundwater, desalinated water, stormwater, roof or rain water, recycled water and River Murray water. Determining an ‘optimal mix’ of water supply options requires considering the trade-offs between multiple objectives such as supply security, economic costs (financial and externalities), social preferences, and environmental impacts.
The tradeoffs analysis methodology that was developed provides a framework that could be applied to other cities/regions to inform the development of total water cycle management plans. The project is innovative because it is the first time that these methodologies to identify options and evaluate trade-offs have been applied at a city-wide scale. This project identified a range of water supply options and evaluated trade-offs at a city scale that best deliver these multiple objectives. The knowledge gained from this complex research project informed policy development and progression of a total water cycle management plan for Adelaide.
Adoption and Impact
This project informed the development of an integrated water management plan for Adelaide in the following ways:
Two-way engagement with decision makers to ensure that the research is targeted towards key knowledge gaps and there is uptake of the project outcomes to support policy development.
The relationship between water sources, water distribution systems and water discharges at a whole of city scale were described and modelled.
Detailed water use patterns of households were measured and applied to understand water demands at a city scale.
An improved understanding of the social preferences and values regarding water supply options was described.
The economic costs and benefits from different supply options was estimated: including capital, operating, energy usage and externalities.
The health and recreational benefits of green space in urban areas was investigated.
An assessment of the institutional arrangements nationally and internationally that support management of diversified water supplies was documented.
A set of methods for determining the tradeoffs between the multiple objectives of alternative water supply options (water security, economic efficiency, environmental benefits, social values and institutional capacity) was developed.