A storm dropped nearly two feet of fresh last week in Big Bear Lake, Calif. (CHRISTOPHER WEBER/ASSOCIATED PRESS)
Much of California’s rain washed away

Much of the torrential rain that fell on Southern California last week flowed right into the ocean, just as downpours did before the state’s epic drought.

That approach once seemed like a good idea, as storm drains provided a defense against flooding. But with California entering what may be a fifth year of drought, agencies are slowly moving to capture and store more of this precious resource.

“That was the 19th-, 20th-century thinking: ‘Let’s get that water out of here as fast as possible,’ ” said Deborah Bloome, senior director of policy at TreePeople, a nonprofit that is working to increase rain capture in the Los Angeles area.

Now people are more likely to see a rapidly disappearing flood — nearly three inches fell on much of Southern California last week — as a wasted opportunity.

The State Water Resources Control Board plans to allocate $200 million for such projects. And Los Angeles plans to capture 20 billion more gallons than the 10 billion it collects during normal years.

“This is a source of water that has been neglected for far too long,” said Peter Gleick, president of the Pacific Institute. The institute authored a 2014 report with the Natural Resources Defense Council that estimated that urban California could capture an additional 630,000 acre-feet of rain a year, roughly enough for 1.2 million households. “It is untapped, and it has enormous potential.”

Southern California imports a lion’s share of its water from Northern California and the Colorado River, on aqueducts that stretch hundreds of miles. The drought has slashed water consumption across the state and renewed interest in developing new water sources such as recycling and seawater desalination.

In Los Angeles, the city gutted a 16-foot-wide concrete street median and replaced it with vegetation that captures rain over 111 acres. The $3.4 million project is designed to collect enough water to fill more than 27 Olympic-size swimming pools a year.

Even smaller projects are being eyed. In November TreePeople unveiled a 1,320-gallon home tank that can be programmed to drain before a storm, making room to capture fresh water. The group plans to equip several more houses by next month.

“We want to show folks this works for El Niño,” Bloome said.