Loma Fire: Homes, roads at risk from winter mudslides and erosion

Oct. 22--The firetrucks are gone, but the damage is far from over in the Santa Cruz Mountains area burned earlier this month by the Loma Fire in southern Santa Clara County.

Officials at the Santa Clara Valley Open Space Authority estimate they will have to spend more than $1 million on emergency erosion control work to stop tons of debris from flowing into nearby creeks, killing wildlife and fouling water supplies if there are heavy storms this winter.

Once thick with oak trees, manzanita and knob cone pines, the slopes of Loma Prieta and Mount Chual, where the fire destroyed 12 homes and blackened 4,474 acres, are moonscapes in some areas, primed for winter rains that could, in the worst case, wreck houses that firefighters had saved.

sjm-lomafire-1023-90A team of geologists, hydrologists, biologists and other experts from the state and federal government spent four days last week inspecting the area. Using helicopter flyovers, soil tests, computer mapping, inspections on foot and satellite images, the eight-member group, known as the Watershed Emergency Response Team, plans to issue a report next week showing which homes and roads are most at risk from winter rains.

"If we have normal winter rainfall, the area will probably be OK. But it's intense storms that we're worried about," said Ed Orre, a division chief and unit forester for the Santa Clara Unit of CalFire, based in Morgan Hill.

Orre said the team has identified 35 homes, 11 bridges, seven culverts, seven road areas and eight other structures at particular risk from mudslides this winter. The areas are along Casa Loma Road, Twin Falls Road and other zones that sit below steep, denuded hillsides.

"There are a couple of places we felt were so much at risk that they may need to put up a barrier, like vinyl walls inflated with water, and sandbags, to divert debris flows and mudslides," said Orre.

Other recommendations the group is likely to include are an emergency notification system, like a reverse 911 plan, in case storms this winter are threatening havoc. The group also will recommend a storm patrol during heavy rain events to monitor culverts and streams, and closing trails in some areas.

Researchers on the team concluded that any storm that brings 1 inch of rain per hour over the winter could trigger mudslides that could threaten homes. The heavy rain last weekend, which dumped 10 inches on the Summit Road area, was close, but it never eclipsed two-thirds of an inch per hour, he said.

Because that was the first big storm of the season, much of the water soaked into the parched ground. Cascades of muddy, silted water did pour into Uvas and Chesbro reservoirs nearby, but didn't flood them with dead trees or other debris that could clog outlet pipes or cause other damage, said Aaron Baker, manager of raw water operations for the Santa Clara Valley Water District.

When the post-fire report comes out, the water district may well install rolled straw mats to control erosion in some places, and put boulders, logs or other materials in water courses to slow debris that could wash into the reservoirs, harming drinking water quality.

"It's something we need to do quickly. It's a priority for us," Baker said.

Other agencies also are concerned. Roughly 43 percent of the land that burned during the fire, which began Sept. 26 and ended Oct. 10, was on land owned by the Santa Clara Valley Open Space Authority.

During a visit recently, Andrea Mackenzie, the agency's general manager, pointed to huge ruts, two feet deep, carved in Mount Chual Spur Road during last weekend's storm. She said her agency expects to spend $1 million or more on rehabilitation projects, such as placing erosion control channels in the dirt roads that traverse the remote area, putting up fencing to block illegal motorcycle riders from further damaging burned slopes and re-seeding less steep areas where seeds have a chance to grow without washing away.

"You can't just reseed it and have it magically come back the way it was," she said. "This will be a long-term recovery."

The agency's Rancho Canada del Oro Open Space Preserve, a popular park west of Morgan Hill, was a base for firefighters to sleep, eat and plan their attack. It remains closed until next Saturday, so crews can repair damaged areas.

For some, erosion and mudslides are the least of their worries.

Mike Dudley, 63, is a carpenter who lived on Mount Chual Spur Road for 30 years in a trailer. He said he loved the rural character and the views across the valley to Mount Hamilton. His home burned in the fire, and he lost nearly everything he owned. Sifting through the ashes on Thursday, he said had no fire insurance. Companies won't insure people in that area because of the risk, he said, and now he's staying with family in San Jose, wondering what to do next.

"You have to start all over again," he said glumly. "I'm old. I can only work a few hours at a time. I'm not sure what I'm going to do. I moved up here because I liked the quiet. It was a really nice wooded spot. But now..."

His voice trailed off. He shook his head, and looked at the blackened ground.

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