Dry wells and channel drains
Hard surfaces and flat lots need different tools. Here's how channel drains, catch basins and dry wells fit in.
Driveways, patios and garage aprons shed water fast. A channel drain, also called a trench drain, is a narrow grated channel set into the pavement that catches sheet flow before it reaches the garage or the house. A catch basin is a box with a grate at a low point in the lawn or patio. Both connect to solid pipe that carries the water to an outlet.
What is a dry well?
A dry well is an underground chamber or gravel-filled pit that holds water and lets it soak into the ground slowly. It's used when a lot is too flat, or too far from a street or ditch, to pipe water anywhere by gravity.
Do dry wells work in Clarksville?
Sometimes, with caution. Two local issues come up:
- Clay soils. A dry well can only release water as fast as the surrounding soil accepts it. In dense clay, that can be slow, so the contractor should test how the soil drains before sizing one.
- Karst rules. TDEC's Underground Injection Control program covers stormwater discharged into the subsurface and modifications of karst features. Ask whether your dry well needs a filing, and never build one into or next to a sinkhole without an engineer and the right permits. Montgomery County requires a 60-foot undisturbed buffer around sinkhole throats, cave entrances and Class V injection wells.
Signs you need a surface drain
- Water running down the driveway into the garage
- Puddles on a patio that slopes toward the house
- Ice forming in the same spot on the driveway every winter
- Erosion at the edge of the pavement
Maintenance
Grates and basins collect leaves, grass clippings and grit. Clean them a few times a year, especially in the fall, and ask for a cleanout or inspection port on any dry well so it can be checked.
The contractor prices the job after walking the yard and seeing where the water comes from and where it can go. We don't quote prices, and any number given over the phone before a site visit is only a rough starting point.
Where we connect you with help
Common questions
Is a dry well the same as a French drain?
No. A French drain moves water away through a pipe. A dry well stores water underground and lets it soak in slowly.
Can a channel drain go across my whole driveway?
Yes, that's a common layout at the bottom of a sloped driveway, as long as it connects to a pipe with a proper outlet.
Related services
More background: Montgomery County drainage guide.
Standing water in the yard or a wet crawl space?
Call now and a local drainage contractor will help you figure out where the water is coming from.