Medium Gravel
- Measuring between 3/4- and 1 1/4-inch grade, medium gravel is composed of stone crushed into irregular shapes. It's used to build foundations for pavements because the sharp edges fit snug together when compacted. If drainage is an issue on your dirt driveway, spread a 2-inch thick layer of medium gravel at ground level over the site. Cover the gravel with a 2-inch thick mix of gravel and dirt. Shape the surface into a crown so the lowest point runs along the sides of the driveway. Once the dirt and gravel are compacted, water will naturally flow off the sides of the driveway.