LOS ANGELES (AP) — As California residents recount the damage from recent storms, some are counting on stormwater captured by reservoirs, wells, cisterns and underground reservoirs — many of which were built in recent years — for relief in a state locked in decades of drought. To give.
Bank rainwater is a rare bright spot. Heavy rain that killed at least 20 peoplecollapsed hills and destroyed thousands of homes.
Los Angeles County, which has 88 cities and 10 million people, collects enough water from the storm to supply about 800,000 people for a year, said Mark Pestrella, director of the Los Angeles County Department of Public Works.
In the four years since Californians passed a measure that would have invested hundreds of millions each year in building small- and medium-sized infrastructure projects that collect rainwater, growth has been slow but not insignificant, experts say.
A new water project in Santa Monica would capture about 2 million gallons (7,600 cubic meters) of runoff, once it would be treated and used for piped irrigation or pumped back into the city’s reservoir.
The project will ultimately save an average of 40 million gallons (151,000 cubic meters) per year, said Sunny Wang, the city’s water resources manager.
Most of the rainwater in California cities eventually flows into the ocean. In Los Angeles, a complex of dams and paved flood control channels divert water away from streets and buildings and into the sea as quickly as possible. The century-old infrastructure was designed to protect the city from flooding.
From the concrete-lined Los Angeles River alone, 58,000 acre-feet of stormwater that begins in the San Fernando Valley and ends at Long Beach Beach has been sent out to sea by recent storms, said Kerjon Lee, a spokesman for the Los Angeles County Department of Public Works. That’s 20% of Nevada’s share of the Colorado River each year.
“What we’re dealing with is a large number, but the catchment area is a small percentage,” Wang said. “Billions of gallons of stormwater flow into Santa Monica Bay every year, so 40 million sounds like a lot, but it’s the first step to making the additional investments we need to make.”
Santa Monica says the sustainable water infrastructure project is the first of its kind in California. Most people don’t even know it exists.
Hidden under the newly covered parking lot near the county courthouse, the wastewater treatment plant filters and simultaneously filters sewage and sewage, producing water that exceeds state and federal drinking water laws.
County officials say the water is being saved — not only to bolster water supplies, but also to prevent stormwater pollutants from entering the Pacific Ocean.
Pestrella, the county’s public works chief, said the floodwaters held over the past few weeks could be enough to prevent Southern California’s Metropolitan Water District, which supplies major population centers including Los Angeles and San Diego, from imposing stricter water restrictions next spring. and summer.
“We need at least three years of this kind of rain,” Pestrella added, to escape the drought.
Much of Los Angeles’ water comes not from the basin itself, but from an extensive storage and supply system that transports snowmelt from the Sierra Nevada in northern California and the Colorado River to the east.
County officials have invested $400 million in a statewide effort to increase local water supplies by capturing rainwater in more than 100 regional projects over the past two years. Officials say they expect the projects in Southern California to be completed within eight years and provide enough water for 500,000 more people in Los Angeles County.
The county’s long-term goal — within the next 30 years — is to collect 300,000 acre-feet of captured floodwater, or enough for up to 900,000 households annually.
Bruce Reznick, executive director of the environmental nonprofit Los Angeles Water Conservancy, said expanding stormwater harvesting projects in Los Angeles is a “race against time” due to drought and the state’s overstretched water sources. He said a slow permitting process was partly to blame.
“We’re starting to make progress, but obviously we have to do better,” Reznick said. “In the last few years, people have become more and more concerned.”
In the Willowbrook neighborhood of South Los Angeles, Ervin “Magic” Johnson Park sits on a former oil field that has since been partially converted into housing. Now, the 104-acre park has two lakes, a playground, exercise equipment and a community center that also collects runoff from storms.
The renovation was in 2010. Completed in 2021. For most people who walk around the lakes, the park is a great place to simply walk. Canada geese hooted from a small island as ducks circled the lake in pairs.
“It’s nice, peaceful and beautiful,” said retired postal worker Barbara Washington Prudhomme.
She didn’t know about the other benefits of the park – a small structure near the lake is recycling dirty rainwater collected from storms, which can flow into the sea and be used to fill the lake or water the grass.
She was impressed when told of the park’s design, which allows it to hold and divert up to 4 million gallons (about 15,000 cubic meters) per storm.
“If it works, it’s a good system,” she said.
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Naishadham reports from Washington DC
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