Rain falls, but hillsides remain in place

The rain was still pounding away Wednesday afternoon behind the added threat of a flash-flood warning for foothill neighborhoods near Station fire burn areas. But as of just before 6 p.m., no damage had been reported in the area.

Though good fortune appeared to be holding for hillside residents, evacuation orders issued Tuesday afternoon remained effective into Wednesday evening for as many as 147 homes in La Cañada Flintridge and 85 homes in La Crescenta.

The National Weather Service reported at 4:50 p.m. that more than 13.5 inches or rain had already fallen since Thursday in burn-affected parts of the Angeles National Forest.

Also on Wednesday, Los Angeles County Supervisor Michael Antonovich declared a countywide state of emergency in order to trigger an assessment of storm damage by state officials that could allow for federal and state assistance if necessary.

An intense group of thunderstorms was predicted to hit hillside areas very early Wednesday morning, but that storm system broke up on approach, blowing east and south to San Bernardino and Orange counties.

“It was really just a blessing,” said L.A. County Fire Department spokeswoman Stephanie English of missing the expected brunt of the weeklong storm cell.

But English and other fire, law enforcement and Department of Public Works officials who were gathered at the coordinated Incident Command Center inside County Fire Camp No. 2 on the JPL campus were urging residents to heed current and future evacuation calls. They emphasized how serious the threat of mud and debris flows from storms is, and will continue to be, for years to come.

“We wouldn’t deploy all this for something that wasn’t very, very real,” English said. “We understand residents are really tired of the message that something very serious could potentially happen, but we want them to know the weather forecasts were dead on. It was a random act of Mother Nature that split those cells off [in other directions] at the last minute.”

Officials were not releasing the locations of homes that were issued evacuation orders by Sheriff’s Department deputies, but many who received them decided to wait out the weather despite warnings.

Though several hillside residents appeared to have left the area before deputies made personal contact, only about a half-dozen of those asked to evacuate chose to comply, said Capt. Dave Silversparre of the Crescenta Valley Sheriff’s Department.

There was little concern for evacuation orders on Tuesday evening among La Cañada residents near the top of Ocean View Boulevard and on Manistee Drive, where the Mullally debris basin is located.

Back in February, a large boulder came down the hillside and choked the Mullally basin, sending a destructive wave of mud and debris toward homes, a pair of which were still under reconstruction this week on Manistee.

“Last time it was OK,” said Ocean View resident Nick Selemi. He continued making dinner despite evacuation calls, and said he would refuse to leave his home. When the Mullally basin overflowed last winter, he said, other residents who had stayed behind then took shelter in his home, which was largely spared from mudflow damage.

Others declined to be interviewed, saying also that they were not heeding warnings to leave.

As Public Works and fire crews continued to monitor conditions near the 28 debris catch basins in the Station fire burn areas, reports as late as Wednesday afternoon were cause for optimism.

The Mullally debris basin that was overwhelmed last winter was no more than 25% full, with others in the area at less than 15% capacity, including the nearby Pickens basin near Mountain Avenue Elementary School, said Public Works spokesman Bob Spencer.

“Following a storm of this length with all the rain we’ve had, that’s fantastic. The debris basins still have lots and lots of capacity,” Spencer said.

Crews have worked since February to clean, repair and expand foothills debris basins.

During this storm, their effectiveness was only bolstered by the fact that not nearly as much debris as expected was coming down hillsides.

“It’s been mostly water so far. When we have steady rain over a period of time — doesn’t matter how long — it doesn’t cause as much of a challenge as when we get dumped on by a lot of water in a very short space of time,” said Spencer.

Thunderstorm pockets did appear to drop short but heavy bursts of rainfall on certain areas throughout Wednesday, flooding portions of some streets, but as of 5 p.m. officials were not forced to respond to any dangerous flood or debris conditions.

Lucy Jones, a chief geologist with the US Geological Survey Office at Caltech and La Cañada hillside-area resident, warned that there’s plenty of debris left up in the burn areas just waiting for a hard enough rain shower to shake it loose.

“What’s important in generating [major debris flow] is the intensity of rainfall, and until this afternoon we didn’t have that much intensity,” said Jones.

While a lot of smaller debris already washed downhill last winter, this week’s rain may just not have been enough to carry down larger chunks of debris that can quickly clog up debris basins.

“What had come down the mountains last time was the fine-grain stuff. The question is whether we’ll get intense-enough rainfall for a long enough time to carry down the [larger debris and] boulders” into basins, Jones said.

Officials are cautioning residents that the dangers of earth and debris movements remain even after this particular storm comes to an end.

“Just because this rain stops doesn’t mean the danger’s over,” said Spencer. “The watershed above us is completely saturated now. The rain isn’t even soaking into the ground — it’s hitting the hillside and skating right off. That can make the hillside very unstable.”