US states' drones inspect bridges, help predict avalanches

In Utah, drones are hovering near avalanches to watch roaring snow. In North Carolina, they're searching for the nests of endangered birds. In Kansas, they could soon be identifying sick cows through heat signatures.

Public transportation agencies are using drones in nearly every state, according to a survey obtained by The Associated Press ahead of its release Monday.

The report from the American Association of State Highway and Transportation Officials shows a sharp increase in their use over the last few years, reflecting the rapid adoption of the technology by governments as well as hobbyists.

In 2016, the nonprofit group found no state transportation agency was using drones on a daily basis. Now, 36 states have certified drone pilots on staff. When the survey was done this month, all but one state was using drones in some way. Since then, the lone holdout Rhode Island has bought a drone, said Tony Dorsey, a spokesman for the group.

The small, unmanned aircraft are often used for mundane tasks, like inspecting bridges and roads. With sophisticated cameras and thermal technology, they can detect tiny cracks and identify potential potholes before they're visible to the human eye.

Drones have caused their share of headaches for officials over the years as personal devices forced the grounding of planes at airports or those fighting wildfires.

But they also can be useful for work that's dangerous for people.

In Utah, drones record from the air as state workers set off planned avalanches, allowing them to watch the slides close up in real time, said Jared Esselman, director of aeronautics at the state Department of Transportation.

Drones also can measure snow and other elements of the state's rugged terrain to keep them from blocking roads or other infrastructure.

"We can predict not only snow slides, but mudslides and water runoff as the snow melts," Esselman said. "Drones are a perfect tool for any job that is dangerous or dirty."