SCE’s Big Creek Hydro Facility Feels Effects of Punishing Drought
Usually by this time of year, Huntington Lake is full, awaiting the arrival of eager boaters and vacationers seeking refuge from the daily grind.
But this year, because the winter snowpack in the Northern Sierra Nevada mountain rangewas only a tiny fraction of what was expected, Huntington is at less than half its normal level.
“It’s shocking to look at,” said Andy McMillan, a manager of Southern California Edison’s Big Creek Hydroelectric Project, which Huntington Lake is a part of.
Boat docks that should be in deep blue water are now abandoned, surrounded by a vast dry and barren lake bed. For the second year in a row, the lake’s annual High Sierra Regatta, organized by the Fresno Yacht Club, has been scrubbed.
Instead, to take advantage of the acres of exposed, rugged lake bottom, rock crawling, an extreme sport that involves driving four-wheel-drive vehicles over boulders and other rough terrain, has taken its place.
California’s punishing drought hasn’t just impacted recreation. It has affected hydroelectric power generation as well.
Huntington Lake is one of six reservoirs that have provided a seemingly endless supply of water for Big Creek, a system of 27 dams, nine powerhouses and 23 generating units that has been called “the hardest working water in the world.”
But lately, that hard-working water has been told to take a rest.
In a typical June, millions of gallons of water per minute would be cascading over Dam 6 near Big Creek’s Powerhouse 8 on the San Joaquin River. Instead, the dam is now releasing about as much water as a single fire hydrant.
“Only enough water is being released to satisfy environmental requirements,” McMillan said. “We’re trying to store as much water as possible for the late summer months.”
Late summer is when Big Creek will be called upon to meet the peak demand for electricity as sweltering customers crank up their air conditioners, he explains.
But for now, powerhouses that are usually humming with the deafening sound of spinning turbines are eerily silent. Their rpm gauges read zero, as the pipelines that bring massive flows of water to drive huge generators are now empty, except for a few trickles.
As California enters its fourth year of extreme drought, SCE estimates that its colossal 1,000-megawatt hydroelectric facility, which was built in the early 20th century to power L.A.’s expansive streetcar system, will only generate about 18 percent of its normal hydropower output this year.
“We are generating very little power at Big Creek because we’re trying to make judicious use of a limited resource,” said McMillan. “We have one (generator) unit out of 23 currently operating.”
In an average year, hydroelectric power from Big Creek fulfills 5 percent of SCE’s energy needs. This year, it will account for only 1 percent, says Colin Cushnie, SCE’s vice president for Energy Procurement and Management.
“The difference will be met predominantly through generation sourced from clean natural gas,” Cushnie said. Additionally, he said that some of the hydro shortfall will be made up with increased purchases of renewable energy, such as wind and solar, which do not have carbon emissions.
“We’re anticipating a little over 1,000 megawatts of new renewable energy resources coming online this year,” he said. “So we’re losing 4 percent of our total energy supply because of the loss in hydro power, but gaining 5 percent in our renewables capacity.”
Cushnie said California has more than enough generating ability to make up for the loss in hydro, but he’s keeping his fingers crossed for a heavy snow this winter.
“If lake levels fall much lower, there’s really not the ability to move water through the powerhouses,” he said. “So we need to get some meaningful precipitation next year in order to pick up our hydro production.”