A wildfire that surged to more than 45 square miles over the weekend in northern Los Angeles County burned five to six homes and damaged a total of 15 structures, fire officials said Monday.
Firefighters appeared to have made major progress Monday night - the 32,000-acre blaze was 60 percent contained. However, the fire still threatened 275 structures and continued to burn into the night, with full containment not expected until next week.
Firefighters said cool overnight conditions on Sunday helped them gain ground as the Powerhouse fire moved into a flat area with less brush, but winds occasionally picked up Monday as crews protect homes near the high-desert city of Lancaster. A higher level of humidity was helping, fire officials said.
The cost of firefighting efforts was estimated at about $8 million as of Monday night.
The vast majority of the 2,500 residents who were under evacuation orders were allowed to return home. Some, however, were not and remained at an evacuation center overnight.
"You start getting a little tired and weary not being in your own home," said Lake Hughes resident Diane Reeves.
"So far, things look much better than they did yesterday," said U.S. Forest Service Cmdr. Norm Walker said at a 4 p.m. news conference.
He expressed "guarded optimism." Full containment was not expected until June 10.
The fire -- which produced smoke that can be seen as far away as Las Vegas, according to the National Weather Service -- grew in rugged terrain that hasn't burned for more than 80 years near Santa Clarita and spread into the Antelope Valley during the weekend.
Lake Hughes resident Dennis Immel, wearing fire gear he bought as a precaution a few years ago, fought off the fire with two hoses.
"My lungs were on fire," Immel said. "There were those ten minutes there where I really got nervous."
Greg Johnson, his neighbor across the street, wasn't as lucky.
"You see something that was once was beautiful, more or less kind of returned back to the elements," Johnson said.
Los Angeles County Sheriff's Department Lt. Dave Coleman said evacuation orders had been lifted for the communities of Lake Hughes at Lake Elizabeth, where about 1,500 people were affected in total.
The community of about 500 people in Antelope Acres, west of the poppy preserve, remained under a mandatory evacuation order.
Evacuation orders could be reinstituted if winds and fire conditions shift, officials cautioned.
A county public health official recommended those who own private wells in affected areas boil their water or drink bottled water as a precautionary measure. The fire could have damaged well or storage tanks, or a power outage could have allowed lines to be de-pressurized and thus decontaminated.
Viewer Images: Powerhouse Fire
Wind speeds are expected to gust Monday at 20 to 25 mph -- not as powerful as during the weekend, but enough to warrant a wind advisory for the area north of Santa Clarita.
"Things are looking better," said Matt Corelli, of the U.S. Forest Service. "Last night was our best opportunity to make some headway on the fire. A cool mass of air came in, that gave us an upper-hand. The fuel the fire is burning into now is a lot less dense than it was up on the hill."
Temperatures in the high 80s are expected Monday. 
The fire broke out Thursday near a hydroelectric plant known as Powerhouse No. 1 in San Francisquito Canyon, north of Santa Clarita in the Angeles National Forest. Flames exploded over the weekend amid 90-degree temperatures and shifting wind gusts, pushing the fire northeast.
"The wind is dropping, and it allows us to get in and do some damage and go direct on the fire," said Sean Collins, of the Kern County Fire Department.
Three firefighters suffered minor injuries while fighting the blaze. One was injured by a falling rock, another suffered from heat stress and a third was injured by contact with poisonous oak.
Lake Hughes and San Francisquito Canyon roads were closed. Bouquet Canyon and Elizabeth Lake roads were open to residents only.
A Red Cross evacuation center is located at Marie Kerr Park, 39700 30th St. W. Palmdale, 93551. About 140 people were at the site, Coleman said on Monday afternoon.
The Antelope Valley Fairgrounds are serving as a shelter for large animals.
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