Before and after: See the impact of California storms from space

Satellite imagery from before and after the atmospheric rivers, which are narrow bands of extreme moisture that produce heavy rain and snow, tell the story of a state that has seen devastating flood damage, rising reservoirs, and billions of gallons of water lost to the ocean after a three-year drought.

Destroyed piers and debris everywhere

Strong winds and waves battered the California coastline, toppling trees and scattering debris. At Seacliff State Beach in Santa Cruz County, the waves washed a piece of an iconic pier into the ocean. In nearby Capitola, the wharf could be closed for a year after massive waves up to 35 feet took a chunk out of a pier and left widespread debris.

President Biden toured both areas Thursday along with FEMA Administrator Deanne Criswell. The damage extends up and down the California coastline with statewide damage estimates ranging from at least $1 billion to as much as $34 billion.

32 trillion gallons of water in 3 weeks: California storms by the numbers

From drought to flooded roads and farmland

The National Weather Service reported a statewide average of 11.47 inches of rain between Dec. 26 and Jan. 17, with some mountain locations receiving upward of 30 to 40 inches of rain. In San Francisco, the 18.09 inches of rain from Dec. 26 to Jan. 16 ranks as the wettest 22-day period since 1862. At one point a flood watch covered nearly the entire state.

The flooding washed out roadways and submerged vehicles across the state. One area particularly hard hit by flooding was Elk Grove and the nearby town of Wilton in Sacramento County where evacuation orders were issued. Water rescue teams were mobilized statewide while in rural areas the flooding wiped out crops including wheat and vegetables.

Sierra Nevada slammed with shocking amounts of snow

Satellite images show the dramatic development of deep snowpack across the Sierra Nevada since early November. Snow totals for the season to date have now reached more than 300 inches for many locations with snowpack averaging about 250 percent of normal for the date.

The current snow depth of 100 to 200 inches would melt down to around 30 to 50 inches of precious water needed to further dent California’s three-year drought. The question is how much of this snowpack will survive through the end of the wet season on April 1 and then supply water for the dry season thereafter.

A dramatic reversal for drought-stricken reservoirs

While some California reservoirs remain only about half full, water levels have risen dramatically in the past two weeks, with many running near or above their historical average. Precipitation and temperature trends over the next few months will determine if reservoirs can maintain or build on current levels by the end of the water season.

The Twitchell Reservoir, about 10 miles northeast of Santa Maria, went from less than 1 percent of capacity on Jan. 7 to 33 percent of capacity as of Wednesday, according to the Santa Barbara County Flood Control District. At Shasta Lake, about eight miles north of Redding, the water level is up from 30 percent in October to 54 percent after the recent storms.

The water that got away

As an estimated 32 trillion gallons of water poured down on California, some of it was trapped by dams and reservoirs, absorbed by soil or captured in underground basins. A lot of it, however, flowed into the Pacific Ocean, carrying particles of soil and rock that can be seen in satellite imagery — in this case obtained by environmental journalism professor Tom Yulsman, who wrote about it for Discover Magazine.

The water lost to the ocean represents a real problem for California — a state that suffers from drought much more often than it does floods — which is how to save up more water for the inevitably drier times ahead. Efforts to capture more rainfall, including new storm water management technology, could help, but such projects are years in the making.

Drought is down, but not necessarily out

Soil moisture estimates based on NASA satellite imagery depict a dramatic swing across California from drier than normal in late December to near-record wetness after the storms, as previously parched pastures and forests have been replaced by saturated soils and flooded farmland.

In October, the federal drought monitor classified 41 percent of California in its top two tiers of drought: extreme and exceptional. That number is now zero. However, more than 90 percent of the state is still classified under milder drought levels.

Editing by Jason Samenow and Julie Vitkovskaya. Video editing by John Farrell. Copy editing by Brian French.