Sonoma Valley thrift store devastated by fire (w/video)

A force of 65 firefighters battled a stubborn, three-alarm blaze at a thrift shop just off Highway 12 in Sonoma on Thursday.

The fire left the concrete block building at 19445 Riverside Drive largely intact, but the roof collapsed and the contents of the Bon Marche Thrift Store warehouse were destroyed, Sonoma Valley Fire and Rescue Battalion Chief John Franceschi said.

Firefighters were unable to breach a corrugated metal subroof between the roof and the interior of the building, the former hatchery of the Nicholas turkey farm converted to a strip mall, he said. Heat and dense black smoke were trapped under the metal sheet, making it difficult to extinguish.

“This fire threw a lot of interesting challenges at us,” Franceschi said.

Employees were holding a meeting prior to opening for business when the blaze erupted in a break room located on a hallway between the thrift shop retail area and the warehouse about 9:30 a.m. One worker grabbed a fire extinguisher and intended to fight the blaze, but was driven back by tall flames, Franceschi said.

The fire quickly spread to the warehouse and office area, but went no farther, he said.

The retail area was not burned, but all the merchandise was ruined by heat and smoke, he said.

Bon Marche is a nonprofit operation that donates proceeds to help women living in poverty in Rwanda.

The fire was under control by noon, and the last engines left the scene at 4 p.m.

Franceschi said the fire crews did “outstanding work” on a blaze that quickly exceeded the resources of the Sonoma Valley department.

The cause is still under investigation but it was “definitely accidental,” he said. Franceschi said he had no estimate of the loss.

Seven command officers, 13 engines, two ladder trucks and two ambulances were involved, with units from Shell-?Vista, Glen Ellen, Kenwood, Petaluma, Santa Rosa and Cal Fire assisting Sonoma Valley.