AUSTRALIAN WATER CONSERVATION AND REUSE RESEARCH PROGRAM

摘要

Security of Australian city mains water supplies is diminishing due to population growth, capped catchments and aquifers, increasing climate variability, lowering of dam spillways, and environmental flow requirements. Yet all capital cities discharge more stormwater and treated sewage than they import from catchments. If irrigation farms had water use efficiencies as low as cities they would be closed. Figure 1 shows the current position, where only 4% of urban roof rainwater and stormwater is harvested and less than 1% of reclaimed water is reused within cities. It also shows a possible future scenario where the draw on catchments could be halved, through a combination of urban water conservation, use of rainwater and stormwater and urban reuse of reclaimed water. Water stresses and physiographic features differ between cities so gross savings and the means of achieving them will also vary. Urban consolidation will also change water usage patterns. Policy changes will be needed to allow water supplies to adapt. Water conservation and reuse to achieve water secure scenarios requires research to underpin policy changes.