Understanding the role of alternative water supply in an urban water security strategy: an analytical framework for decision-making

Abstract

Innovative analytical tools are needed to address complex sustainability challenges in securing water supply for water-stressed, expanding cities worldwide. Melbourne's Alternative Water Atlas is a spatial analytical model that integrates citywide data to evaluate the cost-effectiveness of alternative supply options and their environmental and social benefits. This study presents the methodology employed in the Atlas model to evaluate supply options from four sources (rainwater, stormwater, centralized wastewater recycling, decentralized recycling) to meet the long-term water demand for a range of non-drinking uses in Melbourne. The results of the Atlas analysis highlight preferable options at the local scale with regards to multiple criteria, in order to guide strategic decision-making. Site-specificity and transferability of the Atlas approach are discussed. The Atlas approach can serve as a basis for other international locations to build a locally adapted analytical framework to evaluate the potential of alternative supply options to contribute to water security.

Keywords::

• alternative water sources
• decentralized water supply planning
• urban water management
• water recycling
• water security

Acknowledgements

The authors thank John Briscoe for his support through the Harvard Water Security Initiative.

Funding

NSERC (National Science and Engineering Research Council of Canada) for funding the first author's postdoctoral fellowship.