With El Niño rains returning in earnest, dam operators ramped up water releases Monday from Folsom Lake as a precaution against flooding. They will double the intensity of the releases early Tuesday.
The U.S. Bureau of Reclamation said it raised the release levels to 8,000 cubic feet per second early Monday afternoon, nearly doubling the flow from the weekend. The releases will go to 15,000 cubic feet per second Tuesday morning as a series of winter storms continues to pound the region.
That would be the swiftest release from Folsom since March 2011, when the outflows hit nearly 25,000 cfs.
With more wet weather in the forecast for the next few days, bureau spokesman Shane Hunt said dam operators will continue to watch stormwater flowing into the lake as the week progresses.
“We’ll see how it plays out,” he said. “We may adjust up or down.”
As word got out that the bureau was planning to release more water from Folsom, a Sacramento police helicopter warned campers along the American River Parkway to consider moving to higher ground. Sacramento County officials were considering closing some parkway access points because of flooding concerns.
“The rivers are going to be a little fuller and faster,” said county spokeswoman Chris Andis.
The Sacramento Fire Department on Monday reported that a homeless camp was evacuating with canoes and boats from the same island on Steelhead Creek where the department rescued two homeless campers on Sunday. Later in the day, the fire department reported that it was rescuing two people trapped on an island upstream from the Howe Avenue boat ramp.
Water releases from Folsom have become increasingly controversial, with some area officials saying dam operators should keep as much water in the reservoir as possible as California begins the fifth year of drought. Federal officials, however, say they need to keep Folsom roughly 40 percent empty in winter to guard against flooding, although the percentage varies throughout the season.
Hunt said the bureau began releasing water from the spillway at the top of the dam early Monday afternoon, the first time it had been used in nearly four years. Until now, the bureau has been releasing water through pipes at the bottom of the dam.
Hunt said the use of the spillway doesn’t mean the flood risk has spiked to worrisome levels. Rather, it allows the bureau to keep as much cool water as possible in the reservoir, for use later in the year to help with fish populations and other environmental purposes.
As of Monday morning, the lake was 68 percent full, or 19 percent more full than average for this time of year. Water was flowing in at nearly 26,000 cubic feet per second, or about three times faster than it was being released.
The National Weather Service said rain is expected to continue through much of the week, with a significant storm expected sometime Thursday and on into the weekend. The service said the upcoming weekend could be as wet as last weekend, when the Sacramento area received more rain (1.14 inches) than it did in all of February (0.85 inches). Forecasters said minor flood and travel delays are possible.
Even with the resumption of significant rainfall, it’s unlikely the winter’s precipitation will end the drought. While rainfall amounts vary considerably from city to city, Northern California rainfall as a whole is at 115 percent of average for this time of year. The snowpack, however, is at a statewide average of 82 percent of normal, according to the Department of Water Resources. Historically, multiyear droughts have ended when statewide precipitation hit 150 percent of normal.