How it Works: Maintaining a Dirt Road

A real estate agent once told me of a client who rented a house for a month unseen, made ferry reservations, and drove out to Chilmark, only to discover that his Porsche didn’t have enough clearance to get down his mile-and-a-half dirt driveway. Dirt roads do much to give the Vineyard its rural character, but don’t let their natural appearance fool you – they require more upkeep than Joan Rivers.

Richard T. Olsen, owner of Richard T. Olsen & Son Excavating in West Tisbury, has built and maintained more than his share of dirt roads on the Island.

“It’s all about water,” says Richard. “Whether you’re building or maintaining a dirt road, the first thing you have to do is figure out how to get the water to run off.”

Richard explains that if it’s a major job, say for one of the towns, they’ll usually get an engineer involved to mathematically figure out the best drainage systems, but with years of road-building experience behind him, normally he can determine what has to be done just by looking at it.

“Watch the road during a rainstorm,” explains Richard. “That’ll tell you which way the water wants to go.”

But let’s start at the beginning, because if a road is built right in the first place, it will save lots of headaches down the line. The first step, after the land is cleared, is to take the topsoil away so the road is below grade. Then you start building the road back up. Here on the Island, this is usually done with a mixture of clay and hardener, which is the subsoil mixed with sand. You can blend it yourself or buy it premixed through such Island vendors as Richard’s company, John Keene Excavation in West Tisbury, or Goodale Construction Company in Vineyard Haven. The hardener keeps the road from being too dusty.

“In some places up north, more rock is used,” explains Richard, “but since here the rock has to be shipped in, it can get very expensive. You can also use a crushed stone and stone dust mixture, which makes the road more stable. Stones alone have a tendency to roll away.” A less expensive alternative to crushed stones is RAP – reclaimed asphalt pavement – but it’s not as natural as pure stones.

In locations where there’s a lot of beach sand or where it’s particularly wet, a geogrid is sometimes used. A geogrid is a mesh mat that is laid down at the bottom of the roadbed to provide support so you can build up the surface without having to use expensive rocks. Once the hardener and clay is laid down, a tractor with a grading blade planes the surface down on each side, leaving it “crowned” (built up at the center) so the water falls off to either side.

Finally, the road must be packed down. For this Richard uses a double vibratory drum roller – the drums literally vibrate to create a denser surface that can bear greater loads. Generally, two or three passes will do the job.

In an ideal world, once completed, your dirt road would hold up for years, but unfortunately heavy traffic, storms, and harsh winters can produce potholes within a year. “If the road is constructed properly,” explains Richard, “maintenance shouldn’t be too bad, and it’s better to do a little each year than to let it get out of hand.”

The best way to maintain a dirt road is to build up the holes and ruts with hardener, then roll it out. It doesn’t do any good to just scrape the road down, because you’ll eventually end up below grade and have to start all over again.

“Once the wind and water blows material over to the side of the road,” says Richard, “it turns into what we call ‘dead sand.’ Don’t even try to put that back on the road, because it won’t stay put.”

So what’s your rustic roadway going to cost you?

To build a dirt road from scratch, the general rule of thumb (after the land is cleared) is about $25 to $30 per foot. And to regularly maintain a road could be around $2,000 per mile annually.

But the feeling of that warm sand under your bare feet on an August afternoon