Fire crews work to construct and strengthen containment lines in the steep, remote terrain surrounding the Chute Fire on July 22. Photo Courtesy of CALFire NEU

YUBA COUNTY, CA (MPG) - A wildfire that began as a small vegetation fire near Dobbins grew to 163 acres, prompted evacuations on both sides of the Yuba-Nevada county line and brought more than 1,200 firefighting personnel to one of the region's most difficult landscapes.

The Chute Fire was first reported at approximately 8:20 a.m. July 13 in Chute Ravine near Dobbins. The cause remained under investigation as of Saturday, July 25. The fire's remote location immediately complicated the response. Crews had to hike into the Yuba River drainage carrying equipment while aircraft dropped water and retardant to slow the fire and assist firefighters constructing control lines in the steep canyon.

By the evening of July 13, the fire had grown to approximately 10 acres with no containment. An update on July 15 revised the acreage to nine acres and reported the fire at 20% containment. The fire remained relatively small for several days before flaring up again July 20. The renewed activity prompted an evacuation order for Yuba County Zone YUB-E098 and warnings for surrounding areas, including zones across the river in Nevada County.

Smoke rises from the Chute Fire above Chute Ravine as firefighters contend with steep slopes, loose soil and dense vegetation in remote Yuba County terrain. Photo Courtesy of CALFire NEU

By Monday afternoon, the fire had grown to approximately 33 acres with no containment. Ground crews, air tankers and helicopters continued working to slow its spread, but progress remained difficult because of the steep slopes, heavy vegetation and limited access. The fire reached approximately 84 acres by July 21. Burning logs, rocks and other hot material rolling downhill, a hazard known as rollout, created the potential for the fire to cross control lines and ignite unburned vegetation below.

Although the fire remained relatively small compared with many California wildfires, Yuba County emergency officials said the large response was necessary because of its potential to spread through fuel-heavy canyon terrain toward populated areas.

The Sacramento Regional Incident Management Team assumed command of the fire July 22. Cooler weather that day gave firefighters an opportunity to strengthen containment lines before hotter and drier conditions returned. By the evening of July 22, the fire remained at 84 acres but containment had increased from 1% to 11%. Crews continued constructing hand lines and reinforcing areas where the fire could potentially escape.

Firefighters conducted a planned firing operation overnight into July 23 to improve the containment line along the river. Under selected weather conditions, crews intentionally burned approximately 41 acres of vegetation between the wildfire and the river. Removing that vegetation created a buffer of already burned ground that could slow or stop the fire's spread. The river also served as a natural barrier and provided firefighters with a stronger containment line.

Firefighters watch as a helicopter supports suppression efforts on the Chute Fire near Dobbins on July 22. Photo Courtesy of CALFire NEU

The operation caused the fire's reported acreage to increase to 125 acres July 23, meaning much of the overnight increase came from the planned operation rather than uncontrolled fire growth. Updated mapping later placed the fire at 138 acres and 15% containment. Residents in nearby areas were advised that they could continue to see and smell smoke from the firing operation and smoldering vegetation within the fire perimeter. Aircraft and CAL FIRE's unmanned aircraft systems also were used to identify interior hot spots through infrared imaging. The steep terrain made it difficult for crews to apply water and fully extinguish those areas.

By July 24, updated mapping placed the fire at 163 acres. Containment increased to 30% by the end of the day as crews continued extinguishing hot spots and reinforcing control lines. Evacuation warnings in Nevada County were lifted July 24. In Yuba County, the original YUB-E098 evacuation zone was divided into two sections. Zone YUB-E098-A was reduced to an evacuation warning while Zone YUB-E098-B remained under an evacuation order.

As of Saturday morning, July 25, the Chute Fire remained at 163 acres and was 40% contained, with 1,233 personnel assigned to the incident. Crews continued strengthening containment lines and extinguishing interior pockets of heat, particularly near the river where hot spots remained closest to unburned vegetation. Fire suppression repair work also was underway, with crews working to reduce erosion and restore areas affected by hand lines, equipment and other firefighting activity.

The Yuba County evacuation order and warning remained in place as of the latest update available Saturday, July 25. The cause of the Chute Fire remained under investigation.

CAL FIRE personnel monitor a planned firing operation on the Chute Fire on July 23, when crews burned roughly 41 acres between the fire’s edge and the river to strengthen containment lines. Photo Courtesy of CALFire NEU