El Nino brings flooding concerns to fire-ravaged areas

A lot of rain this season might be a blessing for the Bay Area, although for some people it could become a curse.

In Lake County, where the Valley Fire ravaged the land, there could be major trouble if a strong El Niño amplifies incoming winter storms. And it's not the only part of the Bay Area that could see landslides and flooding. There are a number of hot spots that have officials worried.

Up from the ashes, into the floods

It's been several weeks after the Valley Fire destroyed Kelly Vargas's home and it's far from over.

"It's been a bit of a challenge," she said.  Thankfully, Vargas just secured a permanent home for her and her sons.

"We have two or three more weeks to wait," Vargas said.

And it's not a moment too soon. The fire may be over, but now floods are the new danger. Heavy steady rain could flood a nearby creek putting Vargas's campsite under water.

Although flash flooding and mudslides are not that uncommon during Bay Area winters, this powerful El Niño forecast is cause for concern. A preliminary report on the Valley Fire region highlights more than 100 potential danger areas encompassing 53 homes, 26 bridges and 12 culverts.

"The Cal Fire report has identified that creek as one that could see increased flows and flooding so we're very concerned," said Scott De Leon, the Lake County Public Works director.

Officials in Lake County are concerned enough that survivors living in tents and trailors may be forced to leave. FEMA is coming to the rescue with 100 temporary homes. Now, the challenge is where to put them. The sites have to be safe, sanitary, secure and away from flood zones. 

"I can't imagine what it would be like to a homeowner who has suffered this terrrible tragedy and then have the fortune of a temporary home and the have that damaged by flood," De Leon said.

Cal Fire and chain gangs are clearing the way, lifting dead trees and debris that could clog the flow.

"So that if torrential rain does come it doesn't jump up any culverts, any rivers, any areas that could back up and flood," explained Cal Fire Captain Mike Parkes.

But little can be done on the burnt hillsides. They're baked, baron and look like slabs of rock.

"Instead of there being vegetation there to soak up the rain, it runs off like would on concrete," said Michelle Mead with the National Weather Service.

And it could bring loose soils running down with it. A hydroseed carpet has been put onto bare hillsides along Highway 175 to help prevent slides, debris flow, and possible low lying 

"Could end up with landslide, debris flow, possible low lying flooding," added Parkes.

The run off from all the burned hillsides that surround the campsite will eventually end up in Putah Creek and that is a big concern. Putah Creek is just one of the areas USGS is monitoring. Also on the list, Cobb Mountain, Middletown, Hidden Valley and Anderson Springs and the stretch of Highway 175 running through the area.

The USGS has also placed new real time gauges in Putah Creek above Middletown, all for early notification.

"We'll be working with them to monitor and predict and keep track of any flood flows in the creek," said De Leon. The National Weather Service is also customizing watches and warnings.

Slipping ground

The Valley Fire area isn't the only problem. Heavy rainfall linked to a strong El Niño in 1997-1998 claimed lives, caused over $150 million in damage and created 300 slides. With a large portion of the Bay Area on sloping ground, if history repeats itself, many spots will be at risk.

USGS will be monitoring the soil in Marin, the East Bay hills and two spots on the peninsula.

"We plug instruments into the ground, into the soil, it's hooked up to data logger, it tells us how wet soil is," said Brian Collins is a USGS engineer. "What we're looking for is to see at what point in the season they're completely saturated. The next storm that comes in might cause landslides."

Then there's coastal erosion. The last El Niño that was this powerful eroded Pacifica's cliffs dramatically. Seven homes fell into the oacean, and 12 homes were condemned.  And the problem stretches all the way to San Francisco.

"Pacifica, Daly City, it's a very very weakly cemented sandstone so stands vertically but doesn't take much to erode it," said Collins.

The thought of another strong El Niño year is bringing a wave of fear that reaches all the way from the coast to the inland areas.