BRADY TWP — Motorists using Route 8 in northern Butler County will have a scenic detour through Slippery Rock this summer.

Route 8 will close Monday morning between Route 173 at the Old Stone House and Route 108 for a project to replace the bridge carrying Route 8 over Slippery Rock Creek.

The state Department of Transportation’s posted detour will use Route 173 and Route 108. The about 8-mile detour will direct traffic through the borough, which is home to Slippery Rock University. The detour will be in place until the work is done, which is expected to be October.

This $1 million bridge replacement is being done by JET Excavating.

Borough Mayor Ron Fodor said the increased traffic could cause heavy congestion during the remaining weeks of the school year.

“Certainly as long as the students are there, it’s going to be tough,” Fodor said. “It’s going to be worse during the graduations for the high school and the university.”

About 10,000 vehicles travel on Route 8 at the 173 intersection each day, according to PennDOT statistics. About 6,600 pass the Route 108 intersection on Route 8.

About 11,000 vehicles pass through the Route 173 and 108 intersection daily in Slippery Rock, according to PennDOT.

Fodor said that number drops significantly during the summer when most SRU students are away.

“Traffic isn’t bad when the students are not in town,” he said.

Fodor said he doesn’t anticipate traffic to be a major problem in the borough during the summer, especially when compared to road work elsewhere in the region.

“The little inconvenience in Slippery Rock is nothing,” he said. “And I don’t know of any other solution.”

Fewer than 5,000 vehicles per day typically drive on the soon-to-be closed section of Route 8.

That closed 6-mile stretch of Route 8 will remain open to local traffic, according to Deborah Casadei, a spokesman for PennDOT.

Other traffic will be directed to stay on the posted detour, which uses state roads.

“We try to use state roads for detours,” Casadei said.

Ralston, Kiester and Branchton roads connect either Route 173 or 108 to Route 8 along the posted detour, and they will be open.

PennDOT also continues more work on two other areas of Route 8 near Butler.

Just north of the city, half of the ramps connecting Route 8 to Route 422 are closed for the summer while those ramps are redone.

Just south of Butler, crews are repaving stretches of Route 8 at night.

Those two areas of work will complete the projects that began last summer. Shields Asphalt Paving is handling the $3 million projects.

PennDOT also plans to begin curb replacement projects in Butler this summer.