For the past three weeks, California has been battered by a series of torrential winter storms. Several regions across the state have already surpassed their annual total rainfall since October, and over 32 trillion gallons of rain have fallen since December 26. But despite three of the driest years on record, much of this precious water has been lost to the ocean.

After a certain amount of rain, the soil becomes saturated and cannot absorb any more water. As a result, the rainwater runs off into nearby waterways, often taking some of the surface soil with it. This can be seen in satellite imagery from the NASA Earth Observatory, which shows caramel-colored sediment swirling around San Pablo Bay, fed by a light-brown Sacramento River.

Satellite imagery of California rainwater
A satellite image shows the swirling sediment along the coast of California, following heavy rainfall and flooding.
Joshua Stevens/NASA Earth Observatory

Sediment can also be seen billowing off the West Coast like snot-colored smoke, showing the soil-laden rainwater spreading into the ocean.

Californian cities were historically engineered to divert stormwater to the ocean as quickly as possible to avoid flooding and property damage. But today, this channelized stormwater represents a missed opportunity. For the past three years, California has been gripped by one of the worst droughts in its history, and this stormwater is now seen as a precious resource worth harnessing.

As of Thursday, California is free from any areas of “extreme” drought—as classified by the U.S. Drought Monitor—for the first time in years. Just three months ago, 41 percent of the state was in this category, and 17 percent was classified as being in “exceptional” drought, the highest drought intensity that the Drought Monitor reports. However, despite the recent rainfall, 92 percent of the state is still classified as being in at least “moderate” drought.

NASA’s satellite image does show some good news, in the form of snowpack in the Sierra Nevada.

“There is a tremendous amount of snow this year, so that’s very encouraging,” Donald Bader, the Lake Shasta area manager for the U.S. Bureau of Reclamation, previously told Newsweek. “That will come down later in the spring when it starts warming up, so we can anticipate that and add that to our [reservoir] storage volumes because we know we’ve got that extra storage sitting up there in the mountains.”

The satellite imagery below shows the comparison between the snowpack on January 23, 2022, and on January 17, 2023:

California satellite image in January 2022
NASA satellite image of California January 2023
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The California Department of Water Resources has calculated that the mountain snowpack across the state sits at 248 percent of its historical seasonal average, with some areas in the southern Sierra Nevada at 292 percent.

On its own, the current weather will not be enough to bring California out of its long-standing drought, but it is a hopeful start.

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