Authorities know where a roughly 25-acre river bottom and grass/brush fire started in Riverbank on Wednesday afternoon, Aug. 20; but the actual cause remains under investigation. The fire was reported shortly after 4 p.m. and broke out near the Stanislaus River on the north side of Highway 108 along Adams Gravel Plant Road.

“It started near a homeless encampment” by the river, said Modesto Fire Department Battalion Chief Jim Black.

Two homes were damaged and one – an unoccupied house in the 4300 block of Mesa Drive in Riverbank – was completed destroyed, as embers from the flame blew across Highway 108 and started fires both on Snedigar Road and Mesa Drive.

“It burned about 25 acres,” added Black. “We had 37 fire engines on scene from several different departments.”

There were also multiple chief officers and two ambulances, along with members of the CERT, Community Emergency Response Team, that responded to provide rehab stations for firefighters.

One firefighter was treated for a heat-related issue and was transported to an area hospital but later released.

Black noted that when the wind picked up, it did blow embers from the fire onto the hillside leading up to the highway from the river bottom area, and crews did an outstanding job keeping the flames from impacting homes in that area. Some embers blew over a half mile away, setting off the fires on the south side of the highway, keeping crews fighting flames in multiple locations.

Some personnel remained on scene throughout the night and into the day Thursday, mopping up hot spots. A portion of Highway 108 between Snedigar and Claus roads was closed for several hours Wednesday afternoon and into the early morning hours Thursday.

Black said crews will continue to routinely check the area for the next few days, and the county’s Fire Investigation Unit is conducting an investigation into the cause of the multi-alarm fire.