Skiing in July, dangerous rivers, full reservoirs: What Sierra’s huge snowpack means for summer

More rain is coming to the Sierra Nevada, adding to a bountiful spring that’s left the snowpack at twice its historical average for this time of year. The mountains are holding more snow than they were two years ago, when Northern California was coming off a historically wet winter that officially ended the drought.

But the heavy spring runoff is frustrating some hikers, campers and rafters. And it’s left farmers in part of the Central Valley frustrated that they aren’t getting full allocations of irrigation water despite one of the wettest winters in years.

The National Weather Service said another round of thunderstorms was expected in the Sierra late Monday and early Tuesday, continuing an unusually wet period that’s confounded forecasters and left Sacramento with the rainiest May in its recorded history.

“Sometimes it’s just hard to turn off the switch,” said weather service forecaster Karl Swanberg. He said dry conditions should return to the mountains for at least another week.

The late spring precipitation has allowed two major ski resorts — Squaw Valley and Mammoth Mountain — to remain open, with Mammoth saying it expects to continue daily operations into August. After getting another three feet of snow in May, Squaw plans to stay open weekends through the end of June. It also plans to be open for the 4th of July weekend.

On the other hand, the late snows have created havoc for some campers and hikers. Tioga Road through Yosemite National Park remains closed, putting some of Yosemite’s most popular hiking trails off limits. On average the road opens by May 26, according to park officials, although it stayed closed until June 29 after the drought-busting winter of 2017.

At Sequoia and Kings Canyon national parks, some of the choicest campgrounds haven’t yet.

Meanwhile, the ample runoff has created dangerous conditions on some of California’s swiftest rivers. In early May, the Placer County Sheriff’s Department reported the death of a Sacramento man who fell into the north fork of the American River while rafting near Colfax. His two companions were rescued. None of the three was wearing life jackets, the department said, which said on social media that recreational rafters should consider staying off the rivers through the end of June.

“If you are not an expert at white water rafting, please DO NOT get into the river,” the department said on Twitter late last week, posting a video of its rescue crews in training.. “There are local professional rafting companies which have the experts and equipment to take you out on the water safely.”

The wet winter and spring have done wonders for California’s water supplies.

Most of the state’s major reservoirs are at or near capacity; Folsom Lake is 115 percent of average for this time of year. Lake Oroville is 98 percent full, and the Department of Water Resources said last week that it’s preparing for the possibility of releasing water on Oroville Dam’s rebuilt flood-control spillway this week.

In early April the spillway was used for the first time since the concrete chute fractured in February 2017, leading to the evacuation of 188,000 downstream residents. The crisis has cost the state $1.1 billion, including repair expenses.

But the water supply is a glass-half-empty situation to one group of farmers: those who live south of the Sacramento-San Joaquin Delta and rely on deliveries from the federal government’s Central Valley Project.

In late May the U.S. Bureau of Reclamation announced that those farmers would receive 70 percent of their contracted supplies.

The farmers think they should get 100 percent. “Sitting with an allocation of (70) percent when we are in one of the wettest years on record is just absurd,” said Tom Birmingham, general manager of Westlands Water District, the largest irrigation agency on the west side of the San Joaquin Valley.

In its announcement, Reclamation said water deliveries are constrained “even in above average water years” by pumping limitations that result from the Endangered Species Act, among other things. Heavy pumping in the Delta has been known to kill endangered salmon and smelt.

President Donald Trump’s administration is trying to ease pumping restrictions, in order to deliver more water to Valley growers. The Trump administration’s blueprint for moving more water through the Delta is expected to be released within the next month. Reclamation officials say they think they can pump more water without harming fish, but environmentalists have vowed to fight any efforts to remove limitations.

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