ST. PAUL, Minn. - The Minnesota Department of Transportation could soon be going high-tech in its bridge inspections.
The agency is in the midst of a drone study. It's hoping the technology will help save some money and provide another perspective of how our bridges are holding up.
On the side of a pedestrian bridge in Shakopee, engineers are testing out a drone to look at it up close.
Cameras allow inspectors to see the structure in real-time and detect temperature changes in concrete.
"The biggest benefit is just being able to get out into places that we can't get up close without a lot of equipment or a lot of access methods," said Barritt Lovelace, an engineer for Collins Engineers. MnDOT is contracting with the company for drone testing.
For typical bridge inspections, MnDOT uses trucks, which cost about $675,000 each and can reduce or shut down traffic.
Scott Theisen, a MnDOT engineer, said a drone would cost $40,000 and no traffic backups.
The agency believes drones could save time and money if used on bridge inspections, but Theisen stressed that drones would never replace a real inspector.
"Our best detection is still our hands and eyes in the field," he said.
At the very least engineers say drones are an extra tool to see up close.
"There's always more we can do and this is an effort to try and do a better job and try and improve our inspection technique," said Theisen.
MnDOT will begin its final phase of testing drones this Spring and could begin using them full-time next year.
Theisen said one aspect that has limited engineers' use of drones is that FAA regulations don't allow them to be flown above traffic, for now.
MnDOT reports there are more than 20,000 bridges in Minnesota that require inspection.