2,000 Near Dam Are Evacuated

More than 2,000 residents in Riverside and Orange counties living below the massive Prado Dam were evacuated Friday after engineers detected seepage from the earthen structure, which was holding back near-record levels of water after the region’s recent deluge.

Before dawn, police officers went door to door to 841 homes in Corona warning that the 64-year-old dam on the Santa Ana River was in danger of failing. A neighboring Orange County RV park also was evacuated.

But by midmorning, the U.S. Army Corps of Engineers, which operates and is upgrading the dam, said there was no imminent danger. The seepage, coming from a construction site behind the dam, was “minimal” and had been contained, officials said.

Corona officials, however, were unconvinced. Mayor Darrell Talbert said the evacuations were warranted even if the risk of a breach was small.

“I’d rather be criticized for this than the alternative,” he said. “I can’t jeopardize my residents.”

The city called off the voluntary evacuation Friday afternoon, although the mayor and other city officials urged residents to stay away until Monday, when the water behind the dam was expected to drop to a safer level.

The Prado Dam is visible from the Riverside Freeway, near the Corona Freeway interchange, and is a well-known landmark to motorists because of the 1976 bicentennial mural painted on its spillway. The dam is within a few miles of where Riverside, Orange and San Bernardino counties meet.

A handful of residents decided to return home Friday afternoon, including Rick Wall and his family.

“I’m sure everything’s fine after the chaos of this morning,” he said. “I’ve been getting all the news reports, and I feel fine about returning.”

But several people returned to their homes only to collect a few belongings and said they will wait for the all-clear signal Monday.

“I don’t think [the dam is] going to break, but you don’t want to be stupid,” Tim Lynch said.

The Corps of Engineers detected the water seepage Thursday afternoon when workers noticed growing dark spots on the downstream face of the dam.

They did not notify emergency operations officials in Riverside, Orange and San Bernardino counties until 10 p.m. Thursday. The delay was one reason Corona officials said they were frustrated by what they called poor communication with the federal agency.

“A danger does exist -- the ultimate danger is the dam could fail,” said Corona Councilman Steve Nolan. “If I had kids living in that area, they wouldn’t be back there until Monday.”

The water is coming from a spot at the base of the dam where workers have been building improved outlet gates as part of a $68-million project that will also raise the 105-foot dam’s height by about 30 feet.

To allow for construction, the Corps of Engineers built a 65-foot temporary earthen structure behind Prado Dam. The project is expected to be completed in 2006.

But runoff from the recent record rainfall caused water to rise above the temporary dam and flood the construction area, which is the size of a football field and about 40 feet deep. From the flooded construction area, the water began seeping through the dam, said George Beams, chief of construction for the Corps of Engineers’ Los Angeles district.

To relieve pressure on the dam, the release of water into the Santa Ana River was increased to 10,000 cubic feet per second, the maximum level permitted. On an average day, the dam releases 200 to 500 cubic feet per second.

“If the weather holds, we should have it the level we want it by noon on Monday,” Beams said.

Beams said the water behind Prado Dam stood at 67.5 feet earlier in the week -- 2.5 feet higher than the temporary dam and a few inches lower than the highest level ever recorded, in 1980. The pool of water was so vast that a portion of Corona Municipal Airport, which is in the Prado Flood Control Basin behind the dam, was under water earlier this week.

Beams said the corps made an “economic decision” not to build the temporary dam higher.

“When we’re designing these projects, we are conscious of taxpayer money,” he said. “We made a reasonable judgment to make it the height we made it. Yes, we could have made it 30 to 40 feet higher. But that was millions of dollars more.”

The American Red Cross set up an emergency center at Corona High School to serve evacuees. On Friday morning, more than 190 people passed through. By afternoon, most had left for work or school or to stay with friends or relatives.

Diana Charlnoes awoke about 4:30 a.m. to a neighbor banging on her door in the Green River Village Mobile Home Park in Corona telling her of the evacuation. She and her father, Leonard Gares, who breathes through oxygen tubes, headed for the high school.

“We just grabbed the machine, and all his medicine, a few Christmas presents and pictures and left,” said Charlnoes, 35.

“My dad was frightened. He was yelling at us, ‘Let’s just go! Let’s get out of here.’ He has high blood pressure, so that’s what we did,” she said.

Roger and Debbie Thornhill and their five children, ages 10 months to 16 years, live in the mobile home park in the shadow of Prado Dam.

“It is always in your mind when it rains a lot,” Debbie Thornhill said of the dam. “But when the rain stopped Tuesday, we thought it was all over with.”

When her neighborhood began emptying out Friday, her immediate thought was the deadly mudslide in La Conchita in Ventura County earlier in the week.

“I didn’t know what to grab. I was just worried about my kids,” Thornhill said.

As she dressed her 5-year-old son, Caden, he looked up to her and said, “But I don’t know how to swim.”

“That was just heart-wrenching,” Thornhill said.

Bryan Riedl, a member of the Green River Homeowners Assn., spent part of the day at the Backwoods BBQ restaurant in Corona, waiting for the latest news on the evacuation.

“Somebody’s got to get their act together to determine who is in charge of the dam,” Riedl said.

“Who knows the risk? The police, the Fire Department or the Army Corps of Engineers? Why does it take all day to make that decision? Is it a case of who’s going to be sued?”

Prado Dam was built after a massive flood in March 1938 flood killed dozens of people in Orange County.

The dam, completed in 1941, was the first step in an effort by the Corps of Engineers to protect what was once considered the worst flood plain west of the Mississippi River.

Prado Dam allowed Orange County to be developed as suburbs. Without it and subsequent flood-control projects, a flood the size of the 1938 disaster would put 110,000 acres of Orange County under 3 feet of water and cause $15 billion in damage, officials said.

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Times staff writers Mike Anton, Dave McKibben and Seema Mehta contributed to this report.