A gravel trench with a job to do
A french drain is a trench lined with filter fabric, filled with washed gravel, with a perforated pipe running through it. Water in the soil takes the path of least resistance, finds the gravel, drops into the pipe, and runs downhill to somewhere you chose instead of somewhere you did not.
It is not a cure for every wet yard. It is the right tool when water is sitting in the soil or coming at you from a slope. If your problem is water running across the surface off a roof or a neighboring lot, surface grading and downspout extensions often fix it for a fraction of the cost.
French drain pricing in DFW
| Item | Typical range |
|---|---|
| French drain (installed) | $25 to $35 per linear ft |
| Typical residential run | $2,500 to $4,250 |
| Downspout tie in, each | Added per connection |
| Cutting through existing concrete | Added separately |
These are typical installed ranges for the Dallas and Fort Worth market. Your exact number depends on the run length and where the water can legally go, which is why drainage work is always quoted after someone walks the yard.
When a french drain is the answer
- Water stands in the yard for a day or more after rain. The soil is saturated and has nowhere to drain. This is the classic case.
- A slope sends water toward the house. An intercepting drain across the slope catches it before it reaches the foundation.
- One corner of the yard stays soft all year. Usually a low spot with clay under it holding water like a bowl.
- Water is pushing against a retaining wall. Drainage behind a wall is not optional. It is what keeps the wall standing.
- Not the fix: sheet flow off a roof. Extend the downspouts first. That is cheap and it often ends the problem.
- Not the fix: a yard with nowhere lower. A flat lot with no legal discharge point needs a dry well or a pump, not a longer trench.
If you are not sure which of these describes your yard, start with why your yard holds water, which walks through how to read the problem before you pay to solve it.