Driveway Washout

The recent heavy rains and flooding washed out many gravel
driveways and private roads.


The Westmoreland Conservation District has some tips to help with repairs…and to help prevent repeat problems in the future.

Know where the flow is coming from…and take the necessary steps to get the water off your driveway or road

If water is running down your driveway or road, you can add practices to help direct the water off the road and into the nearby terrain.

If water is running across your driveway or road, you can reduce it by adding pipe, clean stone, and fabric in a trench under the driving surface.

Replace the stone

Most driveway stone is one size – 2B.

If you have a long driveway or access road (e.g., more than 200 feet long), you may want to consider using a custom mix of stones called Driving Surface Aggregate.

Applying this aggregate requires specialized equipment to insure that its five different sizes of stone “lock together” when they’re compacted, and produce the most dense and durable surface possible.

With no waterbars or under pipes, water runs down the driving surface, carrying off gravel and soil and scouring ruts.

The pipe in the lower lefthand corner shows an effective way to keep water off the driving surface by directing it from one side of the driveway or road to the other, underneath the driving surface.



A driveway or road that is well-designed and has the type of features described in this article to reduce the flow of water will require only minimal maintenance.

Putting in a new driveway or access road?

Don’t skimp on the prep work!

Start by carefully evaluating the slope of the area where the road or driveway will be. Also look at the type of area around it (e.g., is it lawn or woods or paved?)…and of course, know what direction the water flows.

Be sure to grade your driveway or road in a way that will cause the water to run off of it and away from your home, business, or neighbor. If you can channel the water into a lawn or wooded area, so much the better.

Add pipe underdrains.

Compact the dirt surface so that it is solid.

Add waterbars, if needed.

Add geotextile fabric to prevent the soil from mixing with the stone.

Add the driveway stone or, if appropriate, the driving surface aggregate (remember the latter requires that you have specialized equipment to install it).

Questions? Contact Rob Cronauer, Watershed Program Manager at Westmoreland Conservation District, 724-837-5271 or [email protected] or Chelsea Walker, Watershed Specialist 724-837-5271 or [email protected]

Technical bulletins and information also are available from The Center for Dirt & Gravel Road Studies (CLICK HERE).