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LA Confidential: Storm Water Can Be an Asset, Not a Liability By Nancy L.C. Steele, Ph.D., Council for Watershed Health, and Mike Antos, Council for Watershed Health OAngeles Bureau of Sanitation uses to track quality as water moves fromThe study instrumented six locations withstormwater capture BMPs on varying land-n June 3, 2010, Los Angeles CityCouncilman Tony Cardenas, Los Director Enrique Zaldivar, and Council for the surface through BMPs into the vadose Watershed Health Executive Director Nancy zone, and to groundwater. This six-year data L.C. Steele cut the ribbon on the Elmer collection effort yielded results indicating Avenue Neighborhood Retrofit Demonstra- it was safe to infiltrate polluted surface tion project. Built through a collaborative runoff. The study found no significant trends partnership of federal, state, and local agen- between water quality at the surface and cies and organizations led by the nonprofit water quality in the subsurface. In some Council for Watershed Health, the Elmer cases, the soil water or groundwater quality Avenue project stands as a prime example of improved from the additional inputs. how working across agency boundaries can These findings led to the Elmer Avenue yield innovative solutions. The street was Neighborhood Retrofit demonstration. The retrofitted to demonstrate green infrastruc- through one residential block and a mid- Council and its partners wanted to show a ture/low impact development techniques block alleyway. The streets were in poor landscape that captured rain as a resource. suitable for an urban residential street. condition and lacked sidewalks, curbs, and What resulted is a 24-house block of The goals include increasing water supply, gutters. Underlying the neighborhood, single-family homes in a primarily Spanish- improving water quality, educating residents, however, is the San Fernando basin from speaking and lower-income community and revitalizing the neighborhood. which the City of Los Angeles draws part that was engineered to capture 16 acre-feet of its drinking water supply. Thus an oppor- Located in the San Fernando Valley just during an average rainfall year. tunity presented itself—solve the flooding north of downtown Los Angeles, the problem by redirecting surface flows under- Today, surface flows are captured along Elmer Avenue neighborhood suffered from ground, replenishing the groundwater and Elmer Avenue through BMPs on public and chronic flooding during even small storms. enhancing the community. private properties. Runoff enters two soft- The community had been developed post- bottom catch basins that capture heavier World War II on an ancient floodplain with The first question that had to no storm drain system. On investigation, be answered, however, was it was discovered that surface water runoff whether it was safe to infil- from 60 acres of land flowed primarily trate polluted surface runoff to augment drinking water aquifers. In 2000, the Council and its partners had initiated the Los Angeles Basin Water Augmentation Study. The study asked a simple ques- tion: Can Los Angeles capture and infiltrate stormwater to replenish groundwater supplies? At the time, both the quality and quantity of storm- water made the answer to this question uncertain. 20 SOURCE summer 2012


SOURCE Summer 2012
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