The County of Los Angeles Depart-ment of Public Works and the Sun Valley Watershed Stakeholders Group, including TreePeople, completed an innovative plan to control flooding in an urban watershed by treating stormwater as a viable resource. Most western US states, including California, are beginning their sixth or seventh year of continuous drought.
Most rainfall in the densely populated urban area collects in storm drains and runs out to the Pacific Ocean. According to the LA County Public Works, a one-inch rain storm can mean the loss of billion gallons of runoff from the LA River watershed. Sun Valley's portion of that water has created chronic flooding that the stakeholders, including government agencies, community groups, businesses and non-profit organisations, intend to tackle at its source.
Their plan to resolve the flooding problem and capture stormwater includes installing systems that mimic the natural functions of undeveloped watersheds by slowing, cleaning, storing and absorbing the water that falls on them. Simple technology practices, such as removing pavement, planting trees and mulching, will be employed. Much of the captured stormwater will eventually replenish local underground water supplies, reducing reliance on the Colorado River, the Eastern Sierra and the Bay Delta, and providing backup water supply in years of scarce rainfall.
Construction of the first project, a stormwater treatment and infiltration facility at Sun Valley Park, is expected to start this summer. For more information, visit the website: www.sunvalleywatershed.org.
