Muddy gravel driveways are one of the perils of rural living. It is possible to have a gravel driveway that remains dry and solid even in the wettest weather. Designing the driveway so that water drains away from the surface is the easiest way to ensure a firm driveway, however, it is possible to make improvements to your existing driveway to keep it dry and trouble free.
Channel water away from the driveway. Water doesn't have to run across the surface of the road to create problems. Water that pools on one side of the driveway can saturate the ground, softening the base under the gravel. When you drive on the softened base, the weight of the car and the spinning tires mixes the base into the gravel, creating mud. Use a shovel or a commercial ditch digger to create ditches parallel to each side of the driveway. Leave a small shoulder between the edge of the gravel and the ditch that slopes downward toward the ditch. This not only prevents water from pooling on the driveway, but also provides a way for water to drain off the driveway's surface.
Add gravel to low spots. Use a shovel to fill in any low spots to prevent them from filling with water the next time it rains.
Create a crown. Once you address the holes and low spots, go back over the driveway adding gravel to the centre of the road. This creates a crown, which encourages drainage into the ditches. If you were building the driveway from scratch, you could create the crown during the excavating work. Adding gravel to create a crown is effective; however, you will periodically need to rake the gravel back toward the centre of the road.
Compact the new gravel. Use a plate compactor, tamping bar or roller to compact the new gravel. This will prevent it from shifting under the weight of vehicle traffic and developing low spots.
Maintain drainage ditches. The ditches running alongside your driveway will require regular attention if you want to keep your driveway in good condition. You may need to rake out leaves in the fall, or pick up branches and other debris after storms. Periodically, you will need to use a shovel to scrape back excess soil that slides down into the ditch, which will obstruct the flow of water.