WASHINGTON, DC A March survey of state departments of transportation found that 33 state DOTs are either already using or considering aerial drones for a range of possible cost-and time-saving tasks, including bridge inspections and even helping allocate assets to clear vehicle crashes.

AASHTO, which conducted the survey, reported the results that featured some of the unmanned aerial vehicles and agency officials who are testing their use in official business. Seventeen state DOTs told AASHTO they have researched or used drones, while another 16 say they are considering UAVs for certain tasks. The report, which also named states that are already exploring drone use, drew widespread media attention nationwide.

"That buzzing sound overhead may soon signal the arrival of the 21st-century version of a guy in a hardhat and bucket truck," began a Boston, Massachusetts, -datelined Associated Press story.

AASHTO's announcement cited officials from the Minnesota and Michigan DOTs talking about the benefits UAVs can provide. It also reported that the Vermont Agency of Transportation worked with the University of Vermont using a federal grant to study drone monitoring of rivers to prevent flooding and road damage.

In Minnesota, where the state DOT oversees aviation as well as highway facilities, Director of Aeronautics Cassandra Isackson said, "We've been looking at drones from the perspective of commercial [aviation] operators, businesses, everyone out there using them. The highway side of MnDOT has been exploring them for potential cost savings for things like bridge inspections, surveying and aerial photography."

At the Michigan DOT, Engineer of Operations and Maintenance Steven Cook told AASHTO that UAVs are a safe, reliable, and cost-effective way to monitor traffic flows, obtain photos from inside confined spaces, and gather data on bridge conditions.

"What we found out is that the unmanned aerial vehicle provided a mechanism to keep our workers out of harm's way," Cook said. "A traditional bridge inspection, for example, typically involves setting up work zones, detouring traffic and using heavy equipment. The UAVs can get in and get out quickly, capturing data in near-real time and causing less distraction and inconvenience to drivers."

His department said it could bring substantial savings as well. A traditional bridge deck inspection requires four workers, eight hours and about $4,600, the report said; using a drone takes two operators just longer than two hours, costing an estimated $150.