Residents in the path of a fast-moving fire that broke out north of Boulder on Wednesday were told that their lives were in danger and they needed to get out — but only some heeded the warning, officials said Thursday.

“We were ordering people to leave their homes,” police spokeswoman Sarah Huntley said of the 11,515 reverse 911 calls and dozens of door-to-door officer checks that were made to houses within the path of the Olde Stage Road and Neva Road fires.

But of the thousands who were warned of the impending danger, officials estimated Thursday that only 1,300 to 1,400 homes were actually evacuated.

“From what we can tell, the people who needed to leave, left,” said Barb Halpin, a Boulder County spokeswoman.

Halpin said the county contracts with the Longmont-based private company, Intrado Inc., which issues recorded messages to residents within defined zones during emergencies.

The first round of 150 calls began shortly before 2 p.m., when an electrical line downed by high winds destroyed a home at 7202 N. 45th St. and spread to a nearby field.

The message, Halpin said, “was essentially that there’s a fire in the area, take your stuff and leave.”

Less than an hour later, the company called an additional 10,842 homes from U.S. 36 east to 63rd Street, including the Lake Valley Estates and other smaller subdivisions, Halpin said.

That message, she said, was that “there’s a wildland fire, we’re calling for a mandatory evacuation. Don’t call 911.”

Because the grass fire was contained relatively quickly, Halpin said, it turned out the 10,000 or so calls for evacuation turned out to be “not as critical” as later calls for evacuation and many residents probably chose to stay put and brave the lingering smoke.

Shortly after a second large fire was reported in the area of Olde Stage Road — about a mile directly west of the first fire — the company made three more sets of calls to a total of 523 homes within a few square miles of the flames. Those calls included the Lee Hill and Dakota Ridge neighborhoods, Halpin said.

The areas that received the calls for evacuation, she said, were based on the speed and direction of the fire and the discretion of emergency dispatchers.

Only land lines and voice-over-Internet-protocol phones were called, because the company doesn’t have the ability to call cell phones.

Marcia Purdy, who owns a house and horses at 5075 Niwot Road, said she didn’t get a call because power in the area was out and she only had cordless phones in the house. She said she chose to stay home even though flames had traveled down a nearby ditch to the rear of her house.

“I’ve lived here 25 years and seen a couple fires,” she said. “This was the worst.”

The Intrado computer system that handled the messages called each number up to five times before giving up, and has the capability to log whether a message was left, if someone answered and listened to the whole message or if someone answered and hung up early, Halpin said.

Those logs, however, were not properly faxed to county officials, she said. The company’s servers also “crashed” when they tried to dial too many numbers at once, so the calls were sent out in smaller batches.

It wasn’t clear Thursday whether those issue had been resolved, she added, but no residents lost out on a recorded message because of the issues. An Intrado spokeswoman could not be reached Thursday by phone.

In addition to the calls, Boulder police and Boulder County sheriff’s deputies went door-to-door in some neighborhoods warning people to leave.

Still, some refused to go.

“We go to doors and we say, ‘you’ve got to get out,’” Halpin said. “If people say, ‘I’m going to stay and die in my house,’ we’re not going to haul them off.”

Sarah Huntley, a spokeswoman for Boulder police, said some officers did encounter stubborn residents.

According to police radio traffic on Wednesday, a firefighter sent to the Joder Arabian Ranch, located near the North Foothills Highway and Neva Road, reported that a woman there was refusing to leave the property even with “flames at the door.”

Boulder Sheriff Joe Pelle said Thursday that some homeowners who refused to leave worked alongside firefighters to create “defensible spaces” and spray buildings with garden hoses. Without that help, he said, some buildings might have been lost.