One Month of Rainstorms Boost California’s Water Supply by an Estimated 1 Million Acres

As three raging storms pummeled Northern California in early January, the lakes rose, the floodgates opened, the rivers swelled, and the waterfalls roared.

The landscape that became dry and parched during five years of drought turned into a wet, soggy mess. Trickles of water became surging flows, and floodplains transformed into massive seas of water.

The gallery below of before-and-after images shows the dramatic impact the heavy rains have had on water levels at lakes, reservoirs, dams and rivers across the top half of the state.

The rainfall totals from around Northern California for early January are staggering.

Downtown San Francisco has received 5.53 inches of rain since Jan. 1. The last time the city has seen a number higher than this was 1982 when 7.53 inches fell between Jan. 1 and Jan. 11. During last year’s El Niño year, S.F. had received close to three inches by this date.

More impressive numbers: The coastal range mountains outside Guerneville, where roads and homes went underwater when the Russian River flooded, has received some 21 inches of rain since Jan. 4.

In Downieville, where the Yuba River gushed with a heavy flow all week, some 23 inches of rain were recorded in the past seven days.

The super soakings have filled reservoirs that were mere mud puddles, their cracked lake beds once exposed at the height of the drought that plagued the state for five-plus years and still persists in many regions, especially in Southern California.

The reservoirs in Northern California have gained some million acres of storage in the past seven days, Michael Anderson, a climatologist with the California Department of Water Resources estimates. And total surface storage for the state is roughly 97 percent of average, with the the total storage for the largest reservoirs being at 111 percent of normal.

Lake Oroville, the state’s second-largest reservoir, gained a bit more than 620,000 acre-feet in the first 10 days of January alone.

“That is almost 18 percent of its capacity,” Anderson said. “Since Oroville was about 750,000 acre-feet below its storage limits during flood season (a consequence of the drought), they can keep all that water for future use and largely offset storage impacts from the drought.”

Since January 1, the Northern Sierra 8-Station Index has seen 15.9 inches of precipitation. That number is a measurement of total liquid from rain and melted snow collected at eight stations in the Northern California mountains running from the Cascades to the northern Sierra.

We are already at “almost 32 percent of the annual average of 50 inches,” Anderson said. “As a comparison, in the recent drought, from Jan. 1, 2013 until Feb. 5, 2014 the 8-Station Index only had 16.5 inches inches of precipitation.”

SOURCE: Amy Graff