As the southland was pummeled by the storms last week, Angelenos saw a different Los Angeles River, one that rolls and rages, perhaps reminiscent of the floods that finally prompted the river's channelization.
The storms prompted police to close roads crossing the Sepulveda Basin. Two men and two pitbulls needed rescuing in Cypress Park when they became stuck in a tree as the water rose rapidly. In Boyle Heights, another man needed an extra hand to get out of the water. But, flashier images of swift water aside, there's a more important story that flows along with the currents in the Los Angeles River, one that could help the region cope with its drought problems.
During a storm, the Council for Watershed Health has found that as much as 50 percent of rainfall becomes runoff that gets flushed out into the ocean through the county's 5,000-mile stormdrain system. Along with it come pollutants that many residents just leave on the roadside (such as nearly 1 million cigarette butts on the ground each month, according to L.A. County Department of Public Works estimates in 2010). Residents saw an assortment of trash flow down the river: supermarket carts, plastic bags, shoes and other random detritus.
The sight points to two issues that face Los Angeles during and after a big rainstorm: pollution and water conservation.
First, pollution. Urban runoff is the number one source of pollution in Southern California's waters. Trash ends up in the river coming from all parts of Los Angeles (as you can see if you log onto National Atlas' Streamer). Think twice before leaving a grocery cart on the street or failing to pick up trash on the roadside.
Then, there's water conservation. When filtered and treated, runoff is essentially water that could be used to recharge our local water supplies rather than importing as much as 89 percent from the Colorado River and the Eastern Sierras. It could have supported the needs of 100,000 Angelenos for a year. Instead, it literally went down the drain.
In an article by Jon Christensen and Mark Gold of the UCLA Institute of Environment and Sustainability, the two estimate that three inches of rain in Los Angeles that flowed out to the ocean cost Los Angeles "$176 million a year based on the Metropolitan Water District's average wholesale price for water, which is around $850 per acre foot."
Importing water also has environmental costs, points out the authors. Just three inches of rain that L.A. has to import uses as much carbon dioxide as 80,000 cars a year.
Given this scenario, it seems logical to invest in capturing and storing our water locally. Indeed, more and more projects seem to be on that same track. In Sun Valley, the Elmer Avenue Retrofit Project captures and treats runoff from 40 acres and deposits 16 acre-feet of groundwater back into the local water supply. In Panorama City, the Woodman Avenue Median is already up and running.
Los Angeles has to keep doing more. It has nothing to lose and everything to gain -- more green space, less pollution from moving water, and more water for everyday use.
Photo and video courtesy of Raghu Manavalan.