Two small vegetation fires burning along Highway 166 kept the roadway northeast of the Santa Maria Valley closed for several hours Monday, with reopening not expected until 10 p.m.

At approximately 11:15 a.m., personnel from Cal Fire in San Luis Obispo County, the Santa Barbara County Fire Department and the California Highway Patrol were dispatched to the incidents about 20 miles east of Highway 101.

One fire was quickly contained at less than an acre, but a second blaze burning nearby had charred 5 acres by 2 p.m., with the potential of growing to at least 15 acres, Cal Fire officials said.

The blazes for what was dubbed the Twitchell incident were north of Highway 166.

Initially reported to be moving slowly, one fire’s growth prompted the dispatch of additional personnel at about 2 p.m. as crews battled steep terrain in the area.

By 2:30 p.m., firefighters had stopped the forward progress of the fire and contained 20% of the blaze, but continued handling flare ups into the afternoon. By 6 p.m. they had contained 50% of the fire and expected to remain at the scene overnight.

In addition to multiple engines, a number of aircraft, including a Santa Barbara County Air Support Unit helicopter, were assisting on the incident. 

Other crews dispatched for the incident came from Santa Maria, San Luis Obispo City and Los Padres National Forest fire departments. 

Highway 166 is a narrow two-lane road linking the Central Coast with the Cuyama and southern San Joaquin valleys. When fires occur, crews often use lanes for staging equipment due to the lack of room on the side of the highway.

Due to the firefighting activity, officials called for Caltrans crews to close Highway 166 in both directions between Highway 101 and east of Tepusquet Road. 

As of mid-afternoon, authorities said they expected Highway 166 would remain closed until 10 p.m. 

Firefighting personnel and equipment were expected to still be at the scene on Tuesday so drivers should expect delays on Highway 166, authorities said.

— Noozhawk North County editor Janene Scully can be reached at jscully@noozhawk.com. Follow Noozhawk on Twitter: @noozhawk, @NoozhawkNews and @NoozhawkBiz. Connect with Noozhawk on Facebook.