angel. As Californians assess the damage from recent storms, some are taking stock of rainwater collected by potholes, wells, underground basins and other water catchment systems, much of it lost in recent years of drought. Designed to provide relief to people stuck in decades.
The accumulation of rain water is one of the few positive aspects of the rains, which have claimed at least 20 lives, caused landslides and damaged thousands of houses.
Los Angeles County, which has 88 cities and 10 million people, collected enough stormwater to supply about 800,000 people for a year, said Mark Pestrella, director of the county’s Department of Public Works.
In the four years since Californians passed a bill to spend hundreds of millions of dollars to build small and medium-sized rainwater harvesting infrastructure projects, experts say progress has been slow, but not negligible. .
In Santa Monica, a new project captured about 7,600 cubic meters of runoff, which once treated is used for domestic needs, irrigation, or pumped back into the city’s aquifer.
Sunny Wang, the city’s water resources manager, said the project would save an average of about 151 cubic millimeters per year at the end.
Much of the stormwater that falls on California’s cities eventually flows out to sea. In Los Angeles, a complex system of dams and paved flood control channels divert water from streets and buildings to the sea as quickly as possible. The century-old infrastructure was designed to prevent urban flooding.
From the Los Angeles River alone — along a concrete-lined channel that begins in the San Fernando Valley and ends at the ocean in Long Beach — 71.54 million cubic meters of stormwater was sent out to sea during recent storms, Kergen Lee said. , the spokesperson said. Los Angeles County Department of Public Works. This is equivalent to about 20 percent of Nevada’s allocation of the Colorado River each year.
“It’s a huge amount that we’re capturing, but it’s a small percentage of the watershed,” Wang said. “Billions of gallons of stormwater enter Santa Monica Bay every year, so 40 million sounds like a lot, but it is just a first step toward more investments we must make”.
Santa Monica says its sustainable water infrastructure project is the first of its kind in California. Certainly most people are unaware that it exists.
Hidden beneath a newly paved parking lot next to a county courthouse, the wastewater treatment plant filters and purifies wastewater along with runoff to produce potable water that exceeds state and federal regulations.
County officials say the saved water is critical, not only to augment water supplies, but also to prevent pollutants carried by that stormwater from flowing into the Pacific Ocean.
The county’s public works chief Pestrella said stormwater collected in recent weeks could be enough to stop the Southern California Metropolitan Water District from hitting Los Angeles, San Diego and other major urban centers in the coming spring and summer. Prevents the imposition of water restrictions. ,
To avoid a drought, Pestrella said, “we need at least three years of this type of rain.”
Most of Los Angeles’ water does not come from its own basin, but from a vast storage and supply system that transports snowmelt from the Sierra Nevada mountain range in northern California and the Colorado River to the east.
County officials say the government has invested $400 million over the past two years in more than 100 regional projects, most of them new, in the state’s efforts to increase local water supplies by collecting rainwater. Officials said they expect the projects in Southern California to be completed within eight years and could provide enough water for 500,000 more people in Los Angeles County.
The county’s long-term goal is, over the next 30 years, to collect 370 million cubic meters of stormwater, enough to water 900,000 homes annually.
Bruce Reznick, executive director of the environmental nonprofit Los Angeles Waterkeeper, called expanding the city’s stormwater harvesting projects “a race against time” because of drought and over-exploited water sources in the state. He said the slow permitting process is partly to blame.
“We’re starting to make progress, but obviously we need to do better,” Reznik said. “In recent years, people have become more and more serious.”
In the Willowbrook area of South Los Angeles, Arvin “Magic” Johnson Park was built on a former oil storage area that was later partially converted into a housing project. The now 104-acre (42 ha) park also includes two lakes, a playground, exercise equipment and a community center that collects storm runoff.
The renovations were completed in 2021. For most people walking around the lakes, the park is a nice place to walk. Ducks swim in the lake while Canadian Geese blow horns from the islet.
“It’s safe, quite peaceful and just beautiful,” said Barbara Washington Prudhomme, a Postal Service retiree.
She was unaware of the park’s other benefits, such as the existence of a small structure near the lake that recycles dirty storm water runoff from storm drains that would otherwise flow into the ocean. That water is now used to fill the lake or water the lawn when needed.
She was impressed when she learned that the park’s design allowed it to capture and divert up to 4 million gallons (15,000 cubic metres) per storm.
“It’s a good system if it works,” he said.