Road work along Route 9 in Sullivan and Roxbury is on track to wrap up in spring 2020, according to a N.H. Department of Transportation official.

Work on the slopes along the road to prevent erosion is “substantially complete,” Mark L. Moran, a contract administrator with the department, said via email. Some touch-ups on the slopes may be needed in the event of severe weather, he added.

However, Moran said the replacement of the bridge over Otter Brook could miss its initial Oct. 25 deadline.

“I’m still optimistic but my optimism is waning,” Moran wrote. “Time was lost due to the amount of time it took to install our cofferdam sheeting.”

The work is part of a $13.5 million Route 9 reconstruction project, from the area near Granite Gorge Ski Area in Roxbury to the intersection with Centre Street in Sullivan. Rehabilitation of the Centre Street bridge is also included.

Moran said traffic through the heart of the work zone has been difficult, with tractor-trailer drivers often refusing to use the regional truck detour put in place. The truck detour is meant to keep large vehicles off the narrow roads used to divert cars from the work zone.

“The folks who reside on Valley Road have had it the worst, but I’d be remiss if I didn’t mention the folks in Sullivan who live on Sullivan Road, South Road, Hubbard Road, Centre Street and Sullivan Center Road who have put up with a great deal of truck traffic as well,” Moran wrote. “Folks on Route 123 through Stoddard have dealt with it as well.”

Westbound trucks are directed from Route 9 onto Route 202 in Hillsboro, then to Route 101 in Peterborough to continue west to Keene. Eastbound trucks are detoured to Route 101 in Keene, then to Route 202 in Peterborough and onto Route 9 in Hillsboro.

By the time construction stops for the winter, Moran said, the new Route 9 bridge over Otter Brook should be open to traffic on both sides. Any remaining items will be pushed off until the spring.

While Sullivan’s Little Country Store is still affected by the work, crews were able to remove contaminated soil in front of it ahead of schedule, Moran said.

Jake Lahut can be reached at 352-1234, extension 1435, or You can follow him on Twitter @JakeLahut.