California Snowpack Breaks Record as Drought Conditions Ease

Vehicles drive as snow falls during another winter storm in the Sierra Nevada mountains in Mammoth Lakes, California, on March 10, 2023. Mario Tama/Getty Images

The snowpack in California is at its highest level in decades, bringing drought relief to several regions as well as concerns about flooding from the upcoming snowmelt.

Electronic readings from 130 snow sensors throughout California show that the statewide snowpack’s snow water equivalent was at 61.1 inches on April 3, which is 237 percent of average for this date, according to a press release by the California Department of Water Resources (DWR). This year’s April 1 result from the statewide snow sensor network was found to be higher than any reading since the network was set up in the mid-1980s.

“This year’s result will go down as one of the largest snowpack years on record in California,” said Sean de Guzman, manager of DWR’s Snow Surveys and Water Supply Forecasting Unit.

However, there is a big difference in snowpack measurements by region. While snowpack in the Southern Sierra is at 300 percent of its April 1 average, the Northern Sierra region—where the state’s largest surface water reservoirs exist—is only at 192 percent.

Since 2006, California has been reeling under severe drought conditions that have led to strict water use regulations and even rationing, especially in urban and agricultural regions. Water reservoir levels had plummeted to low levels statewide.

However, beginning in December 2022, multiple storms hit the state, changing the situation in a span of weeks.

According to data from the U.S. Drought Monitor, 80.56 percent of regions were considered to be under “severe drought” conditions in December. This has now dropped to 1.95 percent.

During the same period, regions classified as “none,” meaning areas not under drought, jumped from zero percent to 55.34 percent.

Filled Reservoirs, Flood Risks

California DWR data shows that many of the major water supply reservoirs were filled close to, at, or above their historical average as of April 3. The two biggest reservoirs, Shasta and Oroville, were filled above their historical average.

Aside from relieving drought, the massive snowpack also poses a flooding risk to several regions in California. Flood risk is now more prominent in regions like the southern San Joaquin Valley, the DWR said.

In the Tulare Lake Basin and Lower San Joaquin River, the DWR’s State-Federal Flood Operations Center (FOC) is supporting emergency flood response services.

“This year’s severe storms and flooding is the latest example that California’s climate is becoming more extreme,” said DWR Director Karla Nemeth.

“After the driest three years on record and devastating drought impacts to communities across the state, DWR has rapidly shifted to flood response and forecasting for the upcoming snowmelt,“ she said. ”We have provided flood assistance to many communities who just a few months ago were facing severe drought impacts.”

Groundwater Situation

While the storms have filled reservoirs and boosted snowpack, groundwater basins in the state are yet to recover. Due to this, several rural areas continue to be stressed by water supply issues—especially the regions where people are dependent on groundwater supplies which have been depleted from prolonged drought conditions.

For instance, the long-term drought in the Colorado River Basin has negatively affected water supply for millions of people in California.

In other regions, farmers are capturing the water runoff for “on-farm recharge” purposes, a practice that involves flooding agricultural land during rainy periods to restore groundwater basins. During drought years, groundwater accounts for up to 60 percent of California’s water supply.

However, some environmental groups have raised concerns about the practice, arguing that “on-farm recharge” could lead to pesticides and other contaminants being flushed into drinking water sources.

The Associated Press contributed to this report.