A fast-growing wildfire near Pleasanton grew to 700 acres Tuesday evening, threatening structures and power lines and forcing thousands of residents in the eastern San Francisco Bay Area to prepare to leave their homes.
The Little Fire was 0% contained as it continued to burn near Vallecitos and Little Valley roads in rural southeastern Alameda County, according to the California Department of Forestry and Fire Protection.
Firefighters were contending with limited access and hot weather as they attacked the blaze from the ground with engines, crews and bulldozers and from the air with tankers and helicopters. Cal Fire's Santa Clara Unit and the Alameda County Fire Department were operating under unified command.
Additional resources were arriving from neighboring Contra Costa County, including a battalion chief and five engines, according to ConFire.
Evacuation orders were in effect for six zones covering areas near Pleasanton, Livermore and Sunol. Alameda County warned of a "serious threat to life and property" and ordered people in the affected areas to leave immediately.
- California Fire Tracker: The latest on wildfires across the state
The evacuation area encompassed roughly 4,900 residents, according to an estimate displayed on the Genasys evacuation map. It was not immediately clear how many people had left their homes.
Evacuees were directed to use Highway 84, also known as Vallecitos Road, or Happy Valley Road. A temporary shelter opened at the Pleasanton Senior Center, 5353 Sunol Blvd.
In the Avignon neighborhood, Harmit S. Toor said he was gathering essential belongings after his family's home was placed under an evacuation order.
"I am in the middle of evacuating," Toor said. "We're just trying to be as prepared as possible."
Toor said he, his wife and their two sons were taking passports, important documents and other possessions that would be difficult to replace. They planned to stay with his brother-in-law in the Hayward hills.
As they prepared to leave, Toor said he could see smoke and helicopters flying over his home.
ConFire said the wind-driven blaze was advancing toward the Ruby Hill neighborhood, where about 800 homes surround a golf course.
The evacuation orders also affected rural properties where residents and workers were trying to protect livestock.
Renee Turnbull, 64, rushed to Van Dyke Ranch after learning that the fire had started near the Little Valley Road property where her three horses are boarded.
Turnbull said she saw flames burning across the Koopman and Van Dyke ranches and along a fence line bordering the former power plant property, extending to the top of a hill.
Her horses were safe on the opposite side of the ranch, she said, but she had prepared another option if the fire moved closer.
"If I couldn't get them out with the trailer, I was going to ride one and pony the other two across properties," Turnbull said.
Staff at the Club at Ruby Hill was evacuating golfers, restaurant patrons and employees as sheriff's deputies arrived Tuesday afternoon.
"We're just closing down the golf course, the restaurant, all outlets - clearing people from the course and doing the thing," Marcy Davisson, the club's head of food and beverage, said by phone.
During the call, people could be heard urging others to "Be safe!" and asking, "All the kids are gone?" as employees hurried to put away lawn games and clear the property.
Pleasanton activated its emergency operations center as the fire expanded, City Council Member Julie Testa said.
Testa said she could hear sirens from her home and see smoke in the distance.
"It's not as close to my home as I thought," she said.
The fire began shortly before 3 p.m. and grew rapidly as it moved through grass. Incident commanders requested additional engines, bulldozers and water tenders, while aircraft attacked the fire from above.
The fire produced a large plume that was visible from Oakland and other communities across the Bay Area. Satellite data indicated that the smoke rose as high as about 7,000 feet.
No injuries or structural damage had been reported as of Tuesday evening. The cause remained under investigation.
The blaze broke out as temperatures across the inland Bay Area climbed into the 90s. The National Weather Service issued a heat advisory through 9 p.m. for much of the region, with temperatures expected to reach the mid-90s to low 100s.
Humidity was expected to rise Tuesday evening, potentially improving firefighting conditions, though breezy weather was forecast to continue.
Residents were told not to return until authorities lifted the evacuation orders. Alameda County also asked people, when safe, to check on neighbors who might not have received an alert or who could need help leaving.
AC Alert is the mass-notification system used by Alameda County and its cities.
Anthony Edwards and Sarah Ravani contributed to this report.
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