How to install a driveway trench drain

When it rains hard, the water flowing on surfaces like driveways can't soak into the soil. As more water falls and moves across the hard pavements, it accumulates more potential energy. The water's ability to erode gets greater as more water crosses the driveway faster. If you have a steep driveway and it's really raining hard, the force of the water leaving the driveway might be able to move rocks as big as basketballs.

Where does

the water go?

The first thing you need to study is where the water leaves the driveway. Does the water flow evenly across the entire driveway as it hits the soil, or does it get concentrated because of the shape of the driveway to a small area near the edge of the driveway?

If the water flows across the driveway pretty evenly, then you'll want to put in a trench drain. These are long drains that may be 4, 6 or even 12 inches wide at the top and can be as long as 10, 20 or even 30 feet. They work the same way a gutter collects water at the bottom of a roof.

Installing a drain

If the water from your driveway is heavily concentrated in one location, you may need to install a larger rectangular or square area or field drain. These can be round, square or rectangular. You can find them as small as 12 inches by 12 inches and as large as 18 inches by 30 inches or so. You size the drain to handle the flow of water in the worst storm event.

If you plan to have traffic drive over your drain, you really should install the drain on a poured concrete base. You don't want to make the concrete level because the water may decide to not flow into the drain. Be sure you have the drain low enough to capture the water.

Counteract the force

of the water

When the water exits the trench drain through the pipe that connects to the trench drain, it will have more force than the water entering the drain. The trench drain and the pipe concentrate the water. Many people overlook this.

To prevent erosion where the drain pipe ends, you need to create an area of large rocks that will absorb the energy of the water and disperse this energy. As the water splashes against the rocks as it exits the pipe, the rocks act like shock absorbers.

Spread out the energy

This rock area doesn't have to look like an ugly gravel pit. Use some imagination and obtain some larger decorative rocks to create a nice hardscape feature in your yard. Keep in mind that you want the rocks in this area to be different sizes and shapes so the water energy is spread out. This allows the water to get into the top soil and soak naturally back into the ground like it used to before your home and driveway existed.

-- Tribune Content Agency