It’s really hot. What you need to know about staying cool – and saving electricity

Ease off on your dishwasher and other appliances, if you can. California’s heat wave is approaching record proportions, with multiple days of 100-degree temperatures, soaring demand for electricity and rising danger from forest fires.

Caltrans had to repair four lanes of Highway 50 in West Sacramento that apparently buckled under the heat Sunday, while area officials reported that residents were streaming into temporary “cooling centers” that have opened in recent days.

The National Weather Service predicted that temperatures would top 100 degrees every day through Saturday, peaking at 108 on Thursday. That would mean nine straight days of triple-digit temperatures, tying a Sacramento record for June set in 1981. The longest 100-day heat wave in the region’s history was an 11-day stretch in July 2006, the weather service said. Monday’s temperature of 107 degrees broke the previous record for that day – 105 in 1988.

SMUD and PG&E were dealing with scattered blackouts in their service territories, although power had been restored Monday morning to most customers. Lynsey Paulo, a spokeswoman for Pacific Gas and Electric Co., said only 4,200 customers were without power as of late morning – down from 189,000 customers over the weekend. About 3,000 SMUD customers lost power Saturday, but just 7 were without power as of Monday afternoon.

PG&E officials said extreme heat causes havoc with transformers and other equipment, triggering blackouts even if there’s enough power in the system to serve everyone.

“I would anticipate there are going to be additional outages because of the heat,” said Rod Robinson, manager of PG&E’s Vacaville control center. PG&E expects demand to hit 22,900 megawatts Thursday, eclipsing the record of 22,500 on July 25, 2006.

The manager of California’s power grid, the Independent System Operator, said the state expects to have sufficient power to meet anticipated demands of 47,000 or more megawatts Tuesday and Wednesday. That’s a few thousand megawatts shy of the California record for electricity consumption, which hit 50,270 megawatts July 24, 2006. Nevertheless, spokesman Steven Greenlee said the ISO was directing utilities to postpone maintenance in order to have generators ready to handle spikes in demand.

The ISO also issued a “flex alert,” a call for voluntary conservation measures such as turning thermostats to 78 degrees or higher. The alert will run from 2 to 9 p.m. Tuesday and Wednesday.

One complicating factor confronting utility managers: Heat waves also are rolling through the Pacific Northwest and Arizona, two areas that frequently export their surplus electricity to California.

“If these other areas are dealing with their own heat waves, that could lessen imports available to us,” Greenlee said.

The city of Sacramento said 40 people dropped in at a cooling center at the Hart Center, at 27th and I streets, one of three emergency shelters that opened over the weekend.

That center and at least two others – the Wackford Community Center in Elk Grove and Rancho Cordova City Hall – will be open for drop-ins to escape the heat through Wednesday evening.

At the northern end of downtown Sacramento, Loaves & Fishes was handing out bottled water to its homeless clients and urging them to seek refuge at the organization’s library and other indoor venues. The organization was concerned about those homeless Sacramentans who couldn’t make it to Loaves & Fishes because the heat was too extreme.

“When it’s this hot, people often shelter in place; they don’t come here,” said advocacy director Joan Burke. “Often people try to stay low.”

Emergency services workers advise people to check the county’s website for information on the location and hours of cooling centers, and for private drop-in availability at some churches. Those who do not have internet access can obtain the same information by telephoning 211.

County residents took to social media to complain about broken air conditioning units. Emergency officials asked Sacramentans to check in on elderly neighbors and family members, and urged people without air conditioning to drop in at libraries, shopping malls and other public spaces that are air conditioned.

“People are rightfully complaining about the heat,” said Mary Jo Flynn-Nevins, Sacramento County emergency operations coordinator. “It is hot and it is miserable if you don’t have access to air conditioning.

“Drink plenty of cool water,” she said. “Remember that alcohol and caffeine can dehydrate you. Even in a swimming pool, you can get dehydrated. Get that water intake back into your body.”

Emergency services officials also warned people visiting rivers and lakes that the water is recently melted snow and is very cold, and that rivers are running fast. “It is possible to get hypothermia even on the highest day of the year,” Flynn-Nevins said.

The heat brought other challenges to the region. Caltrans officials said it may have caused the concrete to buckle on Highway 50 in West Sacramento. Several slabs heaved upward, prompting the closure of four lanes Sunday evening and night for repair.

No further buckling problems have been reported, but Caltrans crews are watching that section of freeway for potential problems.

Caltrans pavement engineer Chuy Gonzalez said officials will do a more complete inspection of the area later this week. Buckling is rare, but can occur, Gonzalez said, when wet soil under the freeway becomes overheated and expands.

“My best guess would be expansive soil underneath it,” Gonzalez said. “We had a quick transition from rains a few days ago to 100 degrees now.”

Cal Fire, meanwhile, said it issued an alert because of windy conditions that could quickly turn a spark into a significant fire, mostly in the northern Central Valley. Conditions have been made worse by Northern California’s wet winter, which left a blanket of lush grasses throughout the valley, said Cal Fire spokeswoman Lynne Tolmachoff.

“The potential for starting fires in those areas is going to be high,” she said.

Already, she said, Cal Fire has dealt with 1,900 different fires this year, which is more than usual.

Dale Kasler: 916-321-1066, @dakasler

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