A canal that delivers vital water supplies from Northern California to Southern California is sinking in places. So are stretches of a riverbed undergoing historic restoration. On farms, well casings pop up like mushrooms as the ground around them drops. Four years of drought and heavy reliance on pumping of groundwater have made the land sink faster than ever up and down the Central Valley, requiring repairs to infrastructure that experts say are costing billions of dollars. In wet years, groundwater provides about 40% of the water used in California, but in times of drought, groundwater can amount to 65% of the state's water supply. The slow-motion land subsidence that's occurring—more than 1 foot a year in some places—is not expected to stop anytime soon, experts say, nor will the expensive repairs.
- Last year near Corcoran, the land sank 13 inches in eight months, researchers at NASA's Jet Propulsion Laboratory found by comparing images collected over time from satellites and airplanes.
- Parts of the California Aqueduct, a massive canal that delivers water 400 miles to Southern California, also sank by nearly 13 inches.
- Sinking land has stopped work on part of a historic project to return water flows to an irrigation-depleted section of the San Joaquin River.
"It's shocking how a huge area is affected, but how little you can tell with your eye," says one hydrogeologist. The AP has more
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