The N.W.T. Department of Transportation is trying to minimize the roller coaster bumps in Highway 3 between Yellowknife and Behchoko by installing different types of culverts.

The department says the stretch of road is one of the most expensive sections of highway in the territory to maintain because heat from the road melts the permafrost. The ice expands in the winter and melts in the summers, causing the chipseal road surface to sink.

Rick Menard, senior project officer with the N.W.T. Department of Transportation's highways division, says new culverts will circulate less warm air under Highway 3 and hopefully lessen heaves and dips caused by ice. (CBC)

“When I drive down the road here, every couple of weeks, the dips I'm driving over, they move,” said Rick Menard, senior project officer with the highways division.

“It's almost like it's alive. What we're trying to do is stop that movement. The big thing is to try and keep the temperature in the road at a continuous temperature throughout the year.”

Crews are installing new culverts that are half an arch, instead of a round cylinder. Menard said they will circulate less warm air under the road.

Jan Stirling, the site engineer, said they'll be measuring the temperature in the ground around the culverts and monitoring it in coming years.

"We'll be able to tell what type of temperatures there are — are things staying frozen, is the water warming things up — and be able to make some recommendations for other sections of road."

The department says these lessons will help when constructing buildings, airports or the Tuktoyaktuk to Inuvik all-weather road.