Integrated water cycle management: analysis of resource security

This paper summarises a systems analysis of the impact of Integrated Water Cycle Management approaches on the security of regional water supplies. The synergistic impacts of supply and demand management approaches on the security of regional water supply systems can be accurately evaluated using a combination of non-parametric regional demand methods: the PURRS lot scale water balance simulator and the WATHNET network linear headworks modeal. The systems methodologies described in this paper have widespread application. A case study analyses regional water security in the greater Sydney region to demonstrate the capability of the methodologies. The use of different pump marks for extractions from the Shoalhaven River, various frequencies of water restrictions, rainwater tanks and demand management measures has been investigated. An increase in acceptable frequency of water restriction to 5% and a pump mark of 70% will defer the requirement to augment the water headworks system by 26 years. The use of demand management measures alone will not defer augmentation whilst installation of 5kL rainwater tanks for hot water, toilet, laundry and outdoor uses can defer augmentation beyond 2090. A Pareto diagram is employed to examine conflicting environmental and economic objectives