A wildfire in Sand Canyon that menaced a cluster of homes Tuesday was 70 percent contained Wednesday night with full containment expected Thursday.

The fire burned 1,428 acres and had the potential to explode to 6,000 to 8,000 acres before firefighters curtailed its progression, according to the Kern County Fire Department.

The fire sparked at about 1 p.m. Tuesday when a wheel came off a boat trailer on Highway 58. It started in grass and brush along the westbound lanes of the highway one mile east of Sand Canyon Road. The fire grew quickly, spreading into the canyon and up a mountain.

Capt. Derek Tisinger said control of the fire is expected Friday. Containment means a fire line has been established all the way around the blaze. The fire is controlled when firefighters have gone deeper into the fire and mopped up any hot spots, eliminating any chance for the fire to spring up.

On Wednesday firefighters worked on the north and east flanks of the fire, putting a fire line at higher elevations to try to contain the last half of the fire. Tisinger said 512 firefighters from multiple agencies are on scene.

Wednesday morning, 17 Southern California Edison Co. customers still had no power because of the fire, regional manager Debbie Hess said in a voice message. Hess said six transformers need to be replaced and nine distribution power poles and 13 transmission power poles were damaged.

Efforts to repair the damage are being delayed because a bridge was destroyed by the fire, Hess said.

"At this point in time we haven't been able to get back in there to see the extent of the damage to poles," she said.

When the fire first started, 40 structures in the Sand Canyon community were in danger but fire crews and equipment, including bulldozers and helicopters, prevented the blaze from reaching the homes. The fire torched a vacant home, a bridge and 21 power poles, according to the fire department. There are no reported injuries.

The Tehachapi News reported that the burnt structure was a 100-year-old family home on land that once was the Cameron Dairy Ranch. A landmark old boat on the roadside, bearing the title "SS Minnow," was also blackened by the fire.

The paper reported that the asphalt pavement of the Cameron Creek Bridge at the east end of Tehachapi Boulevard collapsed after the wooden portions burned.

Hand crews respond to the Sand Fire fast because of a new fire suppression camp at the old Monroe High School facility on Eumatillia Street.

After a stressful day Tuesday, Janice Luper, who lives on Pine Canyon Road, said life calmed down Wednesday. On Tuesday while roads were closed, Luper waited an hour and a half with her cancer-laden father in the back seat and her daughters home alone before she was given an escort back to her house.

She said her daughters were a bit scared and her father was a little tired, but the family was doing mostly fine. The power was back on, and the fire appeared to be headed in the opposite direction.

"We can smell smoke and some of the ground is still smoldering," Luper said. "It doesn't seem to be a worry for the houses."

-- Californian staff writer Rebecca Kheel contributed to this report.