Three 500-gallon buckets of water from a helicopter helped douse a three-alarm house fire at 1200 Bear Gulch Road on Saturday, June 2. The helicopter drops stopped an intense fire that had spread to nearby trees from becoming a conflagration that involved the forest, Fire Chief Dan Ghiorso of the Woodside Fire Protection District told the Almanac.

"Luckily it's not too dry yet," Chief Ghiorso said. "It didn't run the hills as easily."

One firefighter was evacuated and treated for heat exhaustion but later returned to duty, Chief Ghiorso said. There were no other injuries, he said. The residents were not at home at the time, and there were no domestic animals involved that firefighters were aware of.

The house is a total loss and uninhabitable, but Chief Ghiorso said he could not yet provide a dollar amount as to estimated losses to the structure and the contents. The occupants were renters whose names were not provided by the district.

Also unknown for the present is the cause of the fire. An investigation began today (June 4), well after the fire was out. "It was so hot, we really couldn't get into it," Chief Ghiorso said. A water tanker truck has been on the scene with firefighters "babysitting the fire" since it was first brought under control on Saturday afternoon.

The first call came in around 1:15 in the afternoon. The battalion chief called a second alarm after seeing a column of smoke from the main fire station at 3111 Woodside Road. Firefighters had things under control by about 3 p.m., the chief said.

In all, 71 firefighting personnel and 27 vehicles responded, including support vehicles, from seven firefighting agencies in the county, Chief Ghiorso said. Along with Woodside Fire were firefighters from the California Department of Forestry and Fire Protection, San Mateo County, Redwood City, San Carlos, Menlo Park and Belmont.

A crew of 15 prison inmates dressed in orange and from a camp in Ben Lomond was called in to cut brush to create a dirt perimeter around the fire, the chief said. "They're a great crew. They do great work," he added.

The "hand crew" program is funded by the state and may be in jeopardy as a consequence of Gov. Jerry Brown's so-called realignment program to gradually transfer responsibility for non-violent prison inmates to the counties.

The fire's impact included about an acre of woodland, including vegetation growing close to the house on the uphill side, within the so-called defensible space zone where ignitable vegetation is not recommended. Firefighters cut down one tree that was too damaged to allow to stand, the chief said.

Fire trucks traveling up Bear Gulch Road, a steep, narrow and winding one-lane road, twice encountered traffic coming the other way that had to back up to find a driveway so as to let the fire trucks through, the chief said.

"It definitely slowed traffic down, but not significantly, to be honest with you," he said. "You can find a driveway pretty quickly."

While fighting the fire, deputies from the San Mateo County Sheriff's Office closed a large section of the road -- about 2,000 or 3,000 feet, Chief Ghiorso said.

Fire hydrants, "few and far between" on Bear Gulch Road, supplied water to fight the fire, but pressure fell off at one point and California Water Service Company shut down some areas of service so as to divert an adequate supply to the hydrants, the chief said.

Chief Ghiorso said the helicopter probably filled its bucket from a lake, but said he did not know for sure.

Are you receiving Express, our free daily e-mail edition? See a sample and sign-up for Express.