The pristine water of Lake Tahoe is blue and clear. The skies above the lake are another story.
“It is hazy,” Kassandra Sjaarda, who works at Sunnyside Restaurant & Lodge in Tahoe City, said Friday. “We can see the other side of the lake, but it looks like fog is rolling across the lake.”
The haze is an outgrowth of the smoke billowing from the Trailhead Fire, which continues to rage in the rugged, forested mountains between Georgetown and Foresthill. Air quality officials say the smoke is likely to affect air quality through much of the holiday weekend, spilling into the Sacramento Valley and permeating the surrounding foothills.
As of Friday evening, the fire had expanded to 2,551 acres, with just 12 percent containment.
The hazy conditions prompted regional air quality officials to issue smoke advisories through Monday in El Dorado, Placer, Yuba and Sutter counties. The Sacramento Metropolitan Air Quality Management District issued a Spare the Air alert through Saturday, in part because of the smoke.
“It’s pretty widespread impacts, maybe not superheavy impacts, but definitely some smoke is in the air and people are finding some irritation from it,” said Ann Hobbs, an air quality specialist with the Placer County Air Pollution Control District.
While air quality officials say they do not want to discourage anyone from having fun outside this weekend, they advised caution for people sensitive to smoke, including children, the elderly and those with heart disease or respiratory issues. Their advice: If you smell smoke and are sensitive to it, head indoors.
“Just use common sense, and don’t overdo it,” said Pamela Diaz, a spokeswoman for the California Air Resources Board.
The National Weather Service warns of “patchy smoke” in the foothills and around Lake Tahoe through the holiday weekend. But there should be some air-quality relief in store for those who choose to stay in the Valley.
“There is going to be a Delta breeze Saturday and Sunday, and that will help a little bit,” said Lori Kobza, a spokeswoman for the Sacramento Metropolitan Air Quality Management District.
Also helpful: The triple-digit heat that has baked the Sacramento region the past week will ease slightly. In the Sacramento region, temperatures are expected to stay in the low to mid-90s through the weekend.
In the Tahoe area, high temperatures will be in the 70s and 80s, said Idamis Del Valle, a weather service meteorologist. The eastern slope of the Sierra could see isolated thunderstorms Saturday afternoon.
The possibility of dry lightning, combined with lots of people with access to fireworks in dry conditions, has fire crews on high alert, said Cal Fire spokesman Daniel Berlant.
“With the risk of Mother Nature-sparked fires, we can’t afford preventable fires right now,” Berlant said.
Dangers associated with wildfires aren’t the only issues folks enjoying the outdoors need to be aware of this weekend. Two of the region’s largest rivers are going to be getting a gush of cold, swift water.
Starting Friday, the U.S. Bureau of Reclamation increased flows below Folsom and Nimbus dams from 4,000 cubic feet per second to 4,500. The flows will increase to 5,000 cfs on Tuesday. Officials urge those boating, fishing and swimming to be mindful of safety as the flows will be fast and cold.
The bureau said the increased river flows are necessary to ensure water quality in the Sacramento-San Joaquin Delta, to maintain adequate flows to the Pacific Ocean and help satisfy obligations to farm contractors who irrigate with Central Valley Project water.
As the outflows increase, Folsom Lake levels will fall, as they do each summer. The reservoir on Friday was filled to 73 percent of capacity, which is just below average for this time of year.
The Feather River below Lake Oroville also is going to be moving faster and higher than usual, said Ted Thomas, a spokesman for the Department of Water Resources.
He said to expect flows up to 9,000 cfs below the Thermalito Afterbay River Outlet. Thomas said the increased releases from Oroville will help meet water-supply needs downstream.