Earlier this month, the future fell on Los Angeles. A long band of moisture, called an atmospheric river, was thrown into the sky. 9 inches of rain in the city More than three days — more than half of what the city typically gets in a year. This is the type of extreme rain that will become more intense as the planet warms.

City water managers, though, were ready and waiting. Like other urban areas around the world, LA has in recent years been a “Sponge city,” replacing impervious surfaces, such as concrete, with permeable surfaces, such as dirt and vegetation. It also created “percolation fields,” where water collects and seeps into the ground.

With traditional dams and all that new sponge infrastructure, the metropolis captured 8.6 billion gallons of stormwater between February 4 and 7, enough to supply water to 106,000 households for a year. For the entire rainy season, LA collected 14.7 billion gallons.

Long dependent on snowmelt and river water, LA is on a quest to generate more water locally. “There’s going to be a lot more rain and a lot less snow, which will change the way we have snowmelt and water capture,” says Art Castro, manager of watershed management at the Los Angeles Department of Water and Power. “Dams and spillways are the workhorses of local stormwater capture for flood prevention or water supply.”

Centuries-old dogma of urban planning dictates the use of sewers, drains and other infrastructure to direct rainwater away from the city as quickly as possible to prevent flooding. Given the rapid destruction Urban flooding Seen around the world, however, it clearly isn’t working anymore, so Now planners are looking for smarter ways. Seizing stormwater, treating it as an asset rather than a liability. “The urban hydrology problem is caused by a thousand small cuts,” says Michael Kapersky, director of the Wheeler Water Institute at UC Berkeley. “No single driveway or roof in and of itself causes a massive change in the hydrologic cycle. But put millions of them together in an area and it does. Maybe we’re going to put a thousand Band-Aids on this problem.” can be solved by

Or in this case, the sponge. The trick to making a city more absorbent is to add more gardens and other green spaces that allow water to collect in aquifers — the porous underground material that can hold water — that cities need. can pull at the time of Engineers are also greening medians and roadside areas to soak up water that normally runs off roads into sewers and eventually the ocean.

As the American West and other regions dry up, they are looking for ways to produce more water themselves rather than importing it. (This strategy includes, by the way, Recycling toilet water into drinking water So cities reduce water use first.) At the same time, Climate change is supercharging rainstorms.Paradoxically enough: for every 1 degree Celsius of warming, the atmosphere can hold 6 to 7 percent more water, meaning there is often more moisture available for storms to dump as rain. In fact, studies have found that West Coast atmospheric rivers, such as the one just hitting LA, Getting wet.