In order to alleviate the continual water demand increases over the limited available water resources non-traditional sources of water shall be part of supply cycle. Detention basins primarily designed for flood control can potentially become part of the solution once some operational aspects are resolved. This book proposes a framework for conjunctive use of detention basins for water supply purposes. The study behind found that this objective can be achieved by adopting a release rule based on storage level and implemented through a mechanism of two levels of spills: The first spill is aimed to ensure continual release of excess inflows before the reservoir achieves full storage to maintain the ability to mitigate floods. The proposed approach was simulated for Brown Hill Creek detention basins in Adelaide, South Australia, and satisfactory results were achieved. A potential yield equivalent to more than 60% of the annual flow was found to be achievable without affecting floodsmitigation and simulation suggest that the proposed approach can be successfully implemented in similar conditions in Australia and throughout the world.