Motorists traveling on the 22-mile stretch of recently repaved road on U.S. Highway 160 from the east edge of Cortez to the top of Mancos Hill might have noticed coarse and smooth sections of the paving job.
The different treatments are part of a test by the Colorado Department of Transportation to determine which of several treatments are most durable, said Jeff Reichle, CDOT project manager.
CDOT used a microsurfacing on the top surface on about a 1-mile section from the Montezuma County Fairgrounds to the Sleeping Ute Rest Area and again for another mile east of Mancos, Reichle said.
In addition, CDOT used nine different treatments on quarter-mile sections of chip-sealing. The treatments varied the size rock from three-eighth of an inch to a half an inch and also varied the asphalt emulsion blend on the surface treatments.
Different amounts of emulsion were used in sections to determine the amount of emulsion that best avoids streaking, which comes on the highway after heavy use from the tires of vehicles, Reichle said.
“We had different applications per square yard, each quarter-mile section was done differently. You can’t tell by eye. After the chip-seal, we went in and placed posts where the sections changed,” he said.
Lisa Schwantes, CDOT spokeswoman, said engineer teams will examine the test sections quarterly for the next few years to monitor how they are holding up.
The total cost of the repaving project was $2.5 million.
Reichle said motorists can spot areas where smooth microsurfacing was done, and they will notice a different road feel when the road switches to coarser pavement where microsurfacing wasn’t done.
The project also used striping changes to create a new eastbound, left-turn lane onto northbound Montezuma County Road 34, near mile marker 48 west of Mesa Verde National Park.
Schwantes said the left turn lane creates a refuge area where vehicles can wait for oncoming traffic to clear at a troublesome spot in the highway where left-turning vehicles have led to crashes.
The restriping to create the left-turn lane required the elimination of the westbound, right-turn acceleration lane out of County Road 34, she said.