Australian Water Management Review Vol 2 2013 | Page 14

Our cities are indeed water supply catchments with the combined total of wastewater and stormwater available in most Australian cities exceeding demand [source: Prime Minister Science Engineering and Innovation Council Working Group (2007), Water for Our Cities: building resilience in a climate of uncertainty, a report of the PMSEIC Working Group, June 2007]. stormwater runoff; and this improved quality enables stormwater to be a significant additional source of supply, particularly for non-potable uses. The establishment of a network of blue-green corridors provides the supplementary drainage system for safe flood conveyance while fostering highly connected spaces for improving and/or returning biodiversity to our cityscapes. The issue of urban heat is growing in its significance. The recent State of Australian Cities report predicts that heatwave-related deaths will more than double over the next 40 years as a result of climate change, ageing population and population growth. Trees and water bodies (lakes and wetlands) have been shown to be a significant cooling effect during the day. Current research within the CRC for Water Sensitive Cities suggests that this cooling is independent of other influential factors and that for each 10% increase in tree cover, the consequential reduction in land-surface temperature is found to be between 0.5°C and 1°C. Furthermore,