WINDHAM – Motorists are being asked to avoid River Road in Windham next week as state crews get busy filling potholes and ruts along most of the crumbling roadway.

Laying fresh tar about three-quarters of an inch thick will offer a temporary Band-Aid, project managers say, until a full reconstruction of the road takes place in coming years.

According to Ernie Martin of the Maine Department of Transportation, the $200,000 overlay project is termed a “maintenance surface treatment” and will take place along much of the almost 10-mile-long road from North Windham to the Westbrook line.

State crews will begin Monday morning and could possibly be done by Thursday or Friday if the weather cooperates, state engineering technician Ben Johnson said. Johnson said crews will begin at Chute Road at 6 a.m. and make their way south toward the Westbrook line. He advises motorists to avoid the road if they can for the next week.

Johnson, who is managing 102 miles of similar maintenance surface treatments this summer for the state, explained that crews have 500 tons of mix that they are allowed to use per mile. Since River Road is severely crowned and rutted, much of the new pavement will be spread on edges and in grooves, with some of the crowned areas receiving little treatment.

“The goal is to make this plowable and we have to stay on yield, so that means we’ll pave a very thin shim on highpoints and fill in the ruts,” Johnson said.

Johnson said he expects to keep one lane open, “but if (motorists) can avoid River Road, we’d certainly appreciate it,” he said.

Some of the road was reconstructed in recent years, including areas near Thayer’s Store in the Gambo/Newhall section, the intersection with Windham Center Road, as well as the section from Route 202 to Chute Road. These sections, except for the Windham Center Road intersection, won’t receive an overlay next week. Johnson said it is easier for crews to repave the short section at Windham Center Road to avoid jointing.

Since River Road has areas under both state and town control, the town of Windham is taking advantage of the state’s project by paying the crew to overlay areas within the town’s domain. Public Works Director Doug Fortier said the town has estimated the work will cost the town $80,000.

“Math is an exact science; paving is not. But we’re estimating the work to cost about $80,000,” Fortier said. Windham, as of July 1, will have about $1.2 million in its road repair budget if the new budget is approved at town meeting June 18.

Fortier, whose department plows River Road in the winter and maintains about 2.5 miles of urban compact zones in the summer, is looking forward to a smoother ride this winter.

“It should help us immensely. We’ll be able to plow more snow off the road. And this overlay should help smooth it out and hold it together for a couple, three years until they can reconstruct it,” Fortier said.

Regarding the full reconstruction project, Martin said he expects to bid reconstruction of the northern section of the road from Route 202 to the Masonic Hall in North Windham in late winter or spring 2013. The $5.9 million project received the Maine Legislature’s approval earlier this spring and is included in the next biennial budget (2012-2013).

The section of River Road below Route 202 and stretching toward the Westbrook line has yet to receive reconstruction funding. Next week’s overlay will have to last at least four or five years on the lower section, assuming the lower section receives Legislative funding in the next budget cycle.

State Sen. Bill Diamond, a Windham Democrat who lobbied on behalf of the full reconstruction project as a member of the Transportation Committee, said the temporary overlay is “just wonderful,” and that “people should consider this as the start of the entire reconstruction of the River Road.”