Reuse of Urban Runoff in Australia: A Review of Recent Advances and Remaining Challenges

Abstract

The degradation of aquatic ecosystems due to hydrologic and water quality impacts of urbanization, combined with increasing water scarcity, has generated increasing interest in the harvesting of urban storm water. This paper reviews the rationale for integrated storm water treatment and harvesting and synthesizes recent advances and trends and knowledge gaps that limit its application. Storm water harvesting is shown to be a viable alternative water supply and to provide a potential solution to the increases in runoff frequency and peak flows that occur as a result of catchment urbanization. In general, treatment technologies for storm water harvesting have been adapted from existing "water-sensitive urban design" approaches, with limited use of traditional water supply and wastewater technologies. Risk management is often lacking, in part due to a lack of relevant guidance. Reported performance shows variable levels of potable water savings, with cases of up to 100% substitution recorded. Costs of storm water harvesting systems are shown to be inversely related to their scale. The limited cost data show the importance of context, with the harvested water costing more or less than alternative supplies, depending on the cost of the alternative. Limited data exist on environmental benefits, such as reductions in pollutant loads and flow peaks. Implementation of storm water harvesting systems is impeded by inadequate data on risk, lifecycle costs, externalities, and water-energy tradeoffs. Furthermore, retrofit of storm water harvesting into existing urban areas is proving to be a challenge, creating an urgent need for specific technologies for use in retrofit situations.

“Grand Paris”: regional landscape change to adapt city to climate warming

“…Improving water quality in the whole metropolitan area will mean restoring the urban water cycle, limiting run-off, and encouraging infiltration and evaporation. The Australian concept of "Water Sensitive Urban Design" (Fletcher et al 2010) is a useful guide here. The banks of the rivers and the new wet areas will be accessible to the population.…”

Quality and seasonal variation of rainwater harvested from concrete, asphalt, ceramic tile and green roofs in Chongqing, China

“…Although many solutions have been proposed, there is much interest in the use of roof-collected rainwater. Rainwater harvesting (RWH) in urban areas is a strategy that brings many benefits and could provide solutions to address current water shortages, urban stream degradation and flooding (Fletcher et al, 2008;Van Roon, 2007).…”

An Overview of Hybrid Water Supply Systems in the Context of Urban Water Management: Challenges and Opportunities

“…Stormwater is considered fit to cater for non-potable water demands and is emerging as a viable option to augment increasingly stressed urban water supply systems [84,85]. The other merit is that it slows stormwater flow, thereby reducing peak flows in waterways [86]. Hence, they have the dual purpose to provide water supply as well as reduce urban flooding [87].…”