The concept goes by different names, sustainable cities, blue-green cities, LID, One Water, to name a few. Seeing water as one, no matter the source, is the future for many seeking to create sustainable urban water supplies as more areas in the country face chronic water shortages and drought.
Envisioning that stormwater and wastewater are actually assets that can become part of the water supply and at the same time provide ecosystems services, recreational opportunities and boost urban resilience is easy. Technology is moving very quickly. However, the regulatory community hasn’t kept up and implementation is hindered by a web regulations all over the country and the lack of documentation that the approach works. Those are two of the main points in a new report by The National Academies of Sciences, Engineering, and Medicine’s Water Science and Technology Board Using Graywater and Stormwater to Enhance Local Water Supplies: An Assessment of Risks, Costs, and Benefits (2016).
Low Impact Development and stormwater rules in place all other the country are facilitating design and installation of tens of thousands of stormwater BMPs to facilitate infiltration. “Because of the absence of ample documentation of costs, performance, and risks, many utilities are hesitant to integrate the practices into their long-term water resource plans beyond the simplest applications. “
Using stormwater and graywater for residential irrigation holds tremendous potential. However, the report notes that neither graywater nor storm water should be used in arid regions to support landscaping that is not sustainable in the long term. “If water conservation is the primary objective, alternative strategies like designing water-efficient landscapes to reduce or eliminate irrigation should first be examined and would provide much larger reductions in water demand in arid regions.” (January 4, 2016 NewTerrain)
Using Graywater and Stormwater to Enhance Local Water Supplies: An Assessment of Risks, Costs, and Benefits
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