(KRON) — California’s reservoirs had incredible transformations this winter as atmospheric rivers soaked the state with rainwater.

Impressive new data released by the California Department of Water Resources on Wednesday shows the state’s second-biggest reservoir, Lake Oroville, is currently at 83% capacity, with 2.9 million acre-feet of water. The largest reservoir in the state, Lake Shasta, is at 85% capacity.

San Luis Reservoir near Gilroy is up to the brim, at 99% capacity, while Cachuma Reservoir in Santa Barbara County is at 98% capacity.

The Department of Water Resources wrote Tuesday, “Storms California has experienced this year have led to one of the largest snowpacks on record. While these winter storms have helped the snowpack and reservoirs, we’re preparing with local agencies for the upcoming Spring snowmelt season.”

Reservoirs look dramatically different this April compared to the past three years, when a severe drought left the state parched for water. California relies on the arrival of winter atmospheric rivers as its annual water source. This winter, the state was drenched by more than a dozen.

Reservoir storage statewide is 107 percent of average for April.

“The real challenge as we move into spring and summer though is flooding, significant flooding, particularly in the Tulare Lake Basin,” said Karla Nemeth, DWR director.

The DWR is monitoring lake levels, weather forecasts, and mountain snow levels to optimize operations for flood control, water storage, and environmental protection while also allowing for carryover storage into 2024.

Water managers are releasing water from Lake Oroville at 10,000 cubic feet per second to provide enough storage space for spring snowmelt. Releases are coordinated with the U.S. Army Corps of Engineers and downstream water operators.