SAN JOSE, Calif. (KRON) — Torrential atmospheric rivers dropped so much water into California’s drought-parched, thirsty reservoirs that four reservoirs in Santa Clara County are now over 100 percent full.

According to water level data released Monday by Santa Clara Valley Water District:

  • Coyote Reservoir : 111 percent full
  • Uvas Reservoir : 105 percent full
  • Almaden Reservoir : 104 percent full
  • Lexington Reservoir : 103 percent full

These reservoirs are so full that spillways activated at all four locations on Monday releasing rainwater downstream. “They are designed to spill,” Valley Water Communication Manager Linh Hoang told KRON4.

Lexington Reservoir’s spillway is seen on Jan. 16, 2023. (Image courtesy SCVWD)

Lexington rose to over 100 percent during Sunday night’s rainstorm. “Lexington Reservoir began spilling last night, marking the first time it’s been full since Feb. 2019. We’re actively monitoring but are not anticipating downstream overflow issues,” SCVWD wrote.

Chesbro Reservoir is nearly full, at 94 percent, followed by Stevens Creek at 85 percent. Reservoirs’ storage and capacity levels are measured using acre-feet (AF).

(Data via Santa Clara Valley Water District as of Jan. 16, 2023.)

The only reservoir left in the county that is not yet half-full is Anderson Reservoir, in the Coyote watershed. Water managers intentionally keep the water level in Anderson — the county’s largest reservoir — low because of a federal mandate and $1.19 billion seismic retrofit project. “We are retrofitting Anderson Dam for safety purposes and we had to lower the levels,” Hoang said.

Precipitation from Sunday night’s storm turned into a blanket of snow up on Santa Clara County’s highest elevations. Video shot by AIO Filmz revealed that Lick Observatory, which sits on the summit of Mount Hamilton, turned into a winter wonderland.

2023’s wild weather has so far included nine atmospheric rivers, a bomb cyclone, and enough Pineapple Express moisture to break 16-day rainfall records in some parts of the Bay Area.

Even after all of that rain, California is still officially in a drought. The California Department of Water Resources said that none of the state’s major reservoirs are at capacity yet. Some are still less than half full.

Latest major reservoir conditions according to the California Department of Water Resources.

The largest reservoir in the state, Shasta, is at 51 percent of capacity, according to CDWR. “Those biggest reservoirs are just so massive it is probably going to take a while for them to fill,” said Alan Haynes, a hydrologist with California Nevada River Forecast Center.

State water officials wrote, “Since Dec 1, 2022, Lake Oroville has seen over a 100ft rise in elevation thanks to a series of atmospheric rivers that delivered significant rain and snow to the Feather River watershed. However, due to historic drought, most major reservoirs, including Lake Oroville, remain low.”

Major reservoirs in Northern California:

  • Shasta : 51% of capacity, 82% of historical average
  • Trinity : 29% of capacity, 49% of historical average
  • Sonoma : 59% of capacity, 101% of historical average
  • Oroville : 56% of capacity, 101% of historical average
  • New Bullards Bar : 79% of capacity, 124% of historical average
  • Folsom : 51% of capacity, 119% of historical average