The Virginia Department of Transportation is testing a way to stretch its maintenance dollars a little further with an experiment on Hogback Mountain Road south of Leesburg.
The gravel road, which leads to Stone Tower Winery, is heavily trafficked, winds over and around hilly countryside, and prone to washing out. VDOT is testing a comparatively new type of road construction—known as full-depth reclamation—on about three-quarters of a mile of that road, starting at the intersection with Rt. 15 south of Leesburg.
“As the name suggests, full-depth reclamation is we dig into the existing roadbed, mix the material with some sort of stabilizer—in this case cement—to stabilize the base underneath, and then put the gravel roadbed back on top,” said VDOT Assistant Director of Transportation and Land Use Sunil Taori. “So it creates stability under the roadbed, so it doesn’t wash off.”
In the case of Hogback Mountain Road, that also means a tar-and-chip hard surface over the road. It also means recycling construction materials right where they are.
“We’re trying to use this treatment on gravel roads to see if we can extend our maintenance dollar, so we don’t have to spend as much of our time and resources maintaining the gravel roads, especially on roads with frequent wash-offs,” Taori said. He said it might mean fewer trips by VDOT crews to pack more gravel and grade on rural roads. The test, he said, will be to see how Hogback Mountain Road handles the winter months.
“Then we’ll see what the results are, and if they are something that we find promising, we could use those in other places, maybe for longer-term treatment, or maybe other applications instead of full asphalt rebuilding,” Taori said.
“There are a couple places where the materials or the process is advantageous,” said Brian Diefenderfer, the Virginia Transportation Research Council associate principal research scientist who co-authored a study on full-depth reclamation in 2011. “One, it’s a cost savings. Two, it’s a way for us to reuse or recycle material, and in some cases, it gives us a better product than what we might ordinarily do.”
In his 2011 study, Diefenderfer found the process showed promise for both saving money and improving roads.
“It’s probably not a fit everywhere,” Diefenderfer said. “It depends on the materials that are underneath. If the foundation has a lot of clay materials, it can be difficult in places.”
Supervisor Tony R. Buffington Jr. (R-Blue Ridge) said he has “a lot of hope” for full-depth reclamation.
“I’m not out to pave our rural roads,” Buffington said. “Our rural roads are a gem, something that we want to save in western Loudoun, but there are some roads that, due to the amount of traffic that they have on them, they need constant improvement.”
He said Hogback Mountain Road, with its steady traffic, hills, and curves, is such a road. If the process works, he said, “it could mean that we found a better solution for when we have to do these improvement along some of our rural roads.”
“Again, I want to make clear that we’re not looking to pave all our rural roads, but if we have to do it—in instances where we have to do it—we want to have the best possible solution that works for everyone, and this does a good job of maintaining the rural, scenic and historic character of these roads.”