(AP) CORONA, Calif. Nearly 1,000 homes were evacuated Friday from the floodpath of a Riverside County dam after water began seeping through an earthen extension of the dam and authorities released millions of gallons into a river to relieve pressure.
"The water's just seeping through it gradually. No hole, no break," said Lt. Col. John Guenther, deputy commander of the corps' Los Angeles district.
"Right now, there is no imminent danger," he said.
However, Corona authorities, defending their decision to evacuate 508 homes, 330 mobile homes and a recreational vehicle park near Prado Dam, about 50 miles east-southeast of downtown Los Angeles.
The water was seeping through the earth of a coffer dam, a temporary barrier surrounding a construction area, at about 10 gallons per minute, corps spokesman Fred Egeler said.
The original dam structure, which is also made of earth, remained firm but as a precaution, the corp was releasing about 10,000 cubic feet of water per second into the Santa Ana River to relieve pressure on the dam.
"That is easily within the limits of the river itself. We're not going to get any flooding," Guenther said.
Corona Mayor Darrell Talbert said the seepage increased fivefold through the night after it was initially detected Thursday evening.
Corona police Chief Richard Gonzales told dozens residents at a Corona High School shelter they should be able to return to their homes Friday afternoon and defended the decision to evacuate the homes.
"I'm sorry if we woke you up, I 'm sorry if we got you out of your home. ... I wasn't gonna lose any of you, period," he said to a round of applause.
The corps told Talbert that a dam break would wipe out the neighborhoods in 21/2 minutes. "That's not a risk I'm willing to take," he said.
The National Weather Service issued a flash flood watch for areas near the Santa Ana River from the dam in western Riverside County to the river's mouth in Newport Beach.
The water release was to continue for two or three more days while crews worked to halt the seepage, Guenther said.
Heavy rains caused the dam to fill earlier in the week and nearby Corona Airport was flooded when authorities released some of the water. Many buildings at the airport remained flooded Friday, although since the rains stopped several days ago the dam itself was only 41 percent full, authorities said.
Meanwhile, to the north, rescuers were flying in food and medical supplies to more than 100 people trapped in a small Angeles National Forest mountain community by a storm-swollen river that has washed out three bridges.
The raging San Gabriel River has cut off ground access to the approximately 135 permanent residents of Follows Camp, which is tucked into a canyon in the rugged forest about 30 miles northeast of downtown Los Angeles.
"We're completely separated from the rest of the world," said Lt. Tim Dowling of the Follows Camp Volunteer Fire Department.
With supplies running low, a Los Angeles County sheriff's search and rescue team flew in food and medical supplies on Thursday. The rescuers also flew out a heart patient needing special medication and a 10-year-old boy who had been visiting friends when he was trapped in the camp with them.
Elsewhere in the region, officials said they would reopen Highway 101 on Friday. The freeway linking Los Angeles to Santa Barbara was shut down this week by a series of mudslides, and had been used as a staging area during the search for survivors of the massive slide in La Conchita.
The San Bernardino Mountain resort communities of Lake Arrowhead and Big Bear were expecting reduced holiday weekend traffic with the continued closure of Highway 330 and Highway 18 due to storm damage. Crews said the roads, key routes into the mountains, weren't likely to reopen for another week.
In Follows Camp, flooding had damaged several cabins and washed out half of the community's fire equipment, including a fire engine that fell into the river. There was also concern that soil left loose by last year's brush fire could slide down into the camp.
The river's water level had risen 22 feet above normal at one point, but it was slowly subsiding, Dowling said.
"It's been tense around here," Dowling said. "We're running out of food, so when we get our food shipped in it should keep the edge off things."
Dowling said he and many residents are drawn to the community by its rustic beauty. The area was originally populated as a gold-mining site in 1862. Follows Camp was founded three decades later by Ralph Follows, an Englishman who moved to San Gabriel Canyon in hopes of finding a cure for his tuberculosis.
About 200 people rents cabins from the campsite's current owners, Patricia Jones and her two sons.
"It's one of the most beautiful places on Earth," Dowling said. "Now it looks like a martian landscape ... It feels like an end of an era to some degree because it's going to be tough to rebuild."