The county has 27 spreading grounds designed to capture rainwater and let it slowly percolate into the ground, to be stored and then drawn out for the summer.
"These basins or these spreading grounds are in areas that are very gravelly, rocky, sandy," said Sterling Kippel, interim assistant deputy director with LA County Public Works. "When we bring in the water it'll slowly percolate, soak deep into the ground and recharge these groundwater aquifers that we have in LA County."
Last winter's intense storms kept the county's groundwater basins well supplied. It was the county's seventh wettest year on record in the last 150 years and more than 200 billion gallons of rainwater were captured - enough to supply 5 million people for a year, Kippel says.
This winter so far has seen a slower start. But the region will see one big storm on Thursday and another over the weekend.
Another source of water for the state is the snowpack in the Sierra Nevada, which fills reservoirs as it melts off after winter.
At this point, the snowpack is below average, but this week's storms should help.
California's snowpack is still below average, but this week's storms should help