Lake Mendocino benefits from high-tech weather forecasting system
Lake Mendocino made it through a typically long, hot summer with an abundance of water and now, thanks to an ongoing experiment with high-tech weather forecasting, the reservoir can retain more water through the winter, benefiting people, fish and farmers along the Russian River.
A dollop of spring rain pumped up the 3-square-mile reservoir near Ukiah, and water managers are now hailing the initial success of an experimental program intended to maximize storage in the second largest source of water for more than 655,000 people in three North Bay counties.
“It looks very promising,” said Jay Jasperse, chief engineer at Sonoma Water, the county agency that delivers Russian River water to 600,000 people in Sonoma and Marin counties. Another 55,000 people and nearly 43,000 acres of cropland from Mendocino County’s Redwood Valley to Healdsburg depend on water drawn from the river’s upper reach.
The new water management program, he said, aims to avoid the “mud puddle syndrome” that occurs when Lake Mendocino falls precipitously low in late summer and early fall.
Households, businesses and prime grape-growing areas, including Alexander Valley, rely on the reservoir, which is also the sole source of water needed to sustain federally protected fish in the upper river.
Officials say there are now about 8,000 more acre feet of water in the reservoir than there would have been without the program, which was implemented last fall.
That may not look like much to the casual observer, but it means more water for boaters and anglers on the reservoir and cooler water for the fish — all while maintaining its role in preventing floods.
“It was a doozy of a year,” said Nick Malasavage, chief of operations and readiness at the U.S. Army Corps of Engineers office in San Francisco, which controls wintertime operations at Coyote Valley Dam, built in 1958 on the east fork of the Russian River. “We prefer to keep things boring.”
High water in the lake kept the South Boat Ramp closed into late spring and Bushay Campground at the lake’s northeast end opened only two weeks ago.
Because Lake Mendocino’s primary purpose is flood control, the reservoir is usually held to 60 percent of capacity during the rainy season from November through February.
For the past 60 years, the reservoir’s operating manual has compelled water releases above the reservoir’s mandated wintertime level at 68,400 acre feet, or 22 billion gallons, to ensure there is sufficient space for inflow from winter storms.
Each acre foot is enough to supply an average California household of four for a year.
But that can be a dicey proposition, given the state’s propensity for swinging from flood to drought.
Local water managers haven’t forgotten the bitter experience of December 2012, when an atmospheric river dumped an unwanted 25,000 acre feet of water into Lake Mendocino.
Officials played it by the book, dumping the water down the Russian River as a precaution against more rain.
But the end of that storm marked the start of a prolonged drought that dropped Lake Mendocino to a mere 25,000 acre feet a year later, exposing vast expanses of dry gravel.
Atmospheric rivers, which deliver up to half of California’s precipitation each year, have been both a drought-busting blessing and a flood-causing curse to the Russian River region.