Post-Fire Erosion 'Always' a Concern

The Gilman Fire is out but the next hard rain on more than 900 acres of blackened hillsides in the Badlands could unleash erosion more damaging than the blaze itself.

Most of the burned slopes face away from the 60 Freeway. Nearly all of the burned area is charged and aimed downhill towards Gilman Springs Road.

"It's all watershed," Cal Fire-Riverside County Chief John R. Hawkins said Tuesday afternoon, standing next to the eastbound 60 before he went into the burned area. "The dirt all runs downhill if it rains, if we have a heavy rain.

"Could be a summer thunderstorm," Hawkins said. "It could wait until wintertime, but there's always the fear of soil transport downhill during a heavy rainstorm. That's causes, if nothing else, erosion problems down below where it can block roads.

"Here, fortunately, there's no homes, so there's no risk there, but there's always the risk of downstream erosion, particularly in soils like this that are this fragile," Hawkins said.

Asked whether there is concern for erosion impacting the 60, Hawkins looked at the burned slopes facing the freeway and did not hesitate.

"Oh there's a risk here, there's a risk of dirt coming down off the hill here, absolutely there's a risk," Hawkins said. "Here the watershed is pretty short, where it can make its run and move dirt, but it can be very dangerous."

Hawkins came to the 945-acre burned area Tuesday afternoon to see where a Cal Fire captain and three inmate firefighters from Oak Glen sustained minor injuries Saturday.

Hawkins took a shovel with him and used it for balance on the steep, unstable slopes.

When he returned, Hawkins remarked on erosion already evident on the black hillsides.

"This is dry erosion, which is just the weight coming down the hill, pushing the dirt," Hawkins said. "You take that dry erosion and you couple it with moisture, it lubricates the granules of dirt and the hillside can come down."

The cause of the Gilman Fire remained under investigation on Tuesday, a Cal Fire spokeswoman said.

The fast-moving blaze was reported just after 4 p.m. Saturday east of Gilman Springs Road and south of the 60 Freeway.

At one point Saturday, as many as 50 motorists were temporarily stranded on the 60 by smoke and ash. California Highway Patrol officers escorted the motorists out of danger.

The burned area was eventually mapped at 945 acres, and the fire was declared 100 percent contained by 6 p.m. Sunday. It was declared 100 percent controlled at midnight Sunday, according to Cal Fire.

Suppression costs were determined to be $479,000, Cheri Patterson of Cal Fire-Riverside County said.