According to Tim Schulte, Richland County engineer, the bituminous pavement on Richland County Highway No. 3 was in very poor condition and because of budget constraints, the potholes were being repaired using aggregate. The road has rolling terrain with several areas of wetland basins on both sides. The wetland areas required numerous grade raise and remained as gravel sections once raised out of the water.
“Typical pavement distresses included transverse, longitudinal and alligator cracking. Numerous potholes and severe rutting were evident throughout most of the project,” said Schulte.
Richland County decided to return the roadway to gravel without reclaiming the existing bituminous roadway. This construction alternative called for placing 4 in. of North Dakota Class 13 aggregate surfacing on the entire 3 miles of roadway and stabilizing this material with Team Laboratory Chemical Corp. ’s Base One Aggregate Base Stabilizer .
“This alternative was the least costly, but the most politically controversial. A public hearing was held to get feedback prior to selecting this alternative. The biggest concern by the public was the loss of a hard surfaced roadway and the potential for dust problems,” stated Schulte. “In preparation for the public hearing, I put together a document showing the costs of maintaining pavement versus gravel, and when it makes sense to pave or de-pave a roadway.” Some of the concerns identified at the public hearing were how the gravel surface would hold up when placed directly over the bituminous. Another concern was whether the moisture would get trapped between the aggregate layer and the old bituminous surface.
“With Richland County’s experience with the base stabilization product, we were confident that we could provide a stabilized aggregate surface over the existing bituminous surface that would shed water and perform like any other gravel surfaced roadway,” said Schulte.
“The County Road No. 3 project was completed on a trial basis. If the project did not go well, we would already have the material in place to reclaim the aggregate and bituminous surface and blend it into a gravel-bituminous mixture for the road surface. The addition of the [base stabilizer] was insurance that the project would be successful,” said Schulte.
Schulte added that the project has been holding up extremely well since its construction in the summer of 2006. In four years, the county has not placed any additional aggregate surfacing with the exception of the areas which have required grade raises due to the ever-expanding wetland basins along the roadway.
