Say goodbye to the last of the gravel roads in Warren ounty maintained by PennDOT.
Construction on 6.7 miles over three roads will begin this week starting with 2.2 miles of Grunderville Road.
Full depth reclamation will be used over Grunderville Road, Bimber Rum Road and Cobham Hill Road, as opposed to cold recycled asphalt that has been used by PennDOT on dirt roads over the past 16 years.
Times Observer photo by Ben Klein
Construction on three of Warren County’s last gravel roads maintained by PennDOT has begun. A road reclaimer owned by the contractor for the project is pictured at Grunderville Road.
That means no more dust kicked up when driving down the road, a salt antiskid can be applied in the winter and less maintenance after the upgrade is complete.
According to PennDOT, studies from Penn State Center for Dirt and Gravel Roads show dust from dirt roads can alter the soil chemistry and negatively impact native vegetation. The sediment can also be carried to streams and rivers as runoff.
Cold recycled asphalt paving was not the best option for the project for a number of reasons, Assistant Highway Maintenance Manager Adam Elms said, including the heavy tree canopy on the roads which slows the curing process. To trim or remove trees would be costly and impact the scenic view, he said.
Cold recycled asphalt paving also requires a temporary project site to be set up. Because of heightened environmental concerns with the roads close proximity to the Allegheny River and the use of thousands of gallons of oil added to the asphalt material, the project is better suited for full depth reclamation, Elms said.
There is also the issue of safety since portions of the roadways are as narrow as 16 feet and the cold recycled asphalt paving requires hundreds of truckloads.
"These roads are better suited for another option," Elms said, and that begins with PennDOT prepping the roadways.
PennDOT maintenance crews cleaned ditches, replaced culvert pipes and cut shoulders.
Midland Asphalt Materials, Inc. of Towanda, N.Y., the contractor for the project, then took core samples of the road to determine the proper mixture of cement and additives needed to reach a certain strength.
Then the big trucks come out.
The roadway reclaimer will pulverize the road to a depth of six inches, including all of the surface base and part of the subgrade, Elms said.
A road grader will follow to shape and smooth out the pulverized material. A cement additive is then spread out and a water tanker is hooked up to the roadway reclaimer, which then blends the soil, water and cement additive together.
The new mixture must be compacted, so a pad foot roller makes a pass followed by the smooth drum roller. Final compacting is done within hours of adding the water and cement mixture to complete the process.
The new road then needs to cure and the surface is kept wet by spraying water on the surface. Traffic on the new surface is minimized for five days during the cure time.
The process will be completed twice more over Cobham Hill Road and Bimber Run Road by July 3, Elms said.
PennDOT will then apply a double seal coat to seal the surface in late July.
During construction, transportation through the work zone on each of the roads will be limited to local traffic only. Flaggers will be on site to facilitate local traffic during operations and all other traffic will be required to use an alternate route.