Durango-La Plata County Airport typically sees a steady flow of airplanes coming and going during daytime operations, including private planes and commercial jets. But as of late, all the activity has stayed on the ground, where a small army of road crews work around the clock to repave the 1.75-mile runway.

The $12.7 million asphalt project has resulted in a 10-day closure of the airport, from Sept. 7 to Sept. 16.

On Thursday, an asphalt milling machine moved slowly along the length of the runway, which is 150-feet wide, removing old asphalt while about 40 trucks hauled it away.

DRO has paused all flights during construction, including cargo, aerial firefighting, emergency medical and military flights.

Director of Aviation Tony Vicari said airport runway maintenance generally happens once every 10 years.

“This runway hasn’t been significantly rehabbed in over 15 years,” he said Thursday. “The asphalt sections on runways are heavily engineered to be able to withstand a lot of landed weight.”

He said the only potential for delay in the project would be if weather forces a work stoppage or if there is an equipment malfunction. DRO and Four Corners Materials have also built redundancy into the project, including an on-site asphalt plant so potential obstacles that emerge do not jeopardize the timeline.

“They ultimately chose the on-site batch plant to maximize the timeline because it cuts down round trips from the batch plant to the job site,” Vicari said.

Crews have been working 24/7 to meet the Sept. 16 deadline.

The project scrapes the existing 3 inches of asphalt off the runway to make way for the new layer. Mounds of old asphalt can be seen sitting around the airport. However, Vicari said the removed asphalt will be reused for airport access roads or taken away by the contractor.

Vicari said around 92% of the $12.7 million project is funded through the Federal Aviation Administration.

“The FAA manages a capital improvement grant system for airports nationwide to invest in critical airport infrastructure that supports the overall National Airspace System,” he said. “Runways are essentially the top priority in terms of funding across the country.”

About $250,000 of the funding came from Colorado Department of Transportation’s Division of Aeronautics and $700,000 came from airport cash funding.

The airport is also taking this chance to redo lights on the runway, switching from incandescent bulbs to LED. Vicari said the change was made to be more energy efficient. After the paving is finished, workers will spend about 20 nights in October grooving the runway for traction. It will take place in late October because the new asphalt needs about 30 days to cure.

The grooving process is slow because it takes time to cut the asphalt with the necessary equipment.

While closed, the airport is making other renovations that would not have been possible while open, including repaving the worn down commercial apron where the planes park on the terminal.

“It’s a difficult surface to work on on a regular basis, because we’ve got aircrafts coming and going all day,” Vicari said. “So the idea of rehabbing active asphalt during times of operation is difficult, if not impossible.”

The airport is also rerouting its fiber-optics service, which is part of a long-term plan for the terminal. That will involve rebuilding some of the existing conduit runs for the system. Vicari said the main purpose is to shift the entry point of the fiber-optic cable.

The closure also gives the airport a chance to make critical repairs to one of its main water pumps.

“We’re actually going to shut down the water system for a couple hours while we change critical components of the distribution pumps, kind of routine stuff in a normal environment,” Vicari said.

The airport will also use the closure to coordinate active-shooter training with staff members and the La Plata County Sheriff’s Office.

“That’s something that we, of course, can do kind of at any point in theory, but it’s a good time when we can pull some of our staff and give them some dedicated time,” he said.

Vicari relied in part on community outreach to decide when the project should be completed. He wanted to make sure the airport closure was not disrupting any major events, such as students returning to Fort Lewis College. He also wanted to make sure the airport was not closed during the peak summer travel and fire seasons.

“We heard very little frustration with dates we chose,” he said. “Of course, there are some individual travel plans that folks had to reconsider. But by setting the dates a year out we provided a long lead time.”

tbrown@durangoherald.com