Does My Yard Need a French Drain in Tennessee? 7 Signs

You likely need a French drain when water soaks into the ground and stays there, such as a soggy lawn patch, a wet spot at the base of a slope, or seepage along a retaining wall. If water runs across the surface or dumps from a downspout, regrading or downspout extensions often solve it more simply.

What does a French drain actually do, and what doesn’t it fix?

A French drain is a trench with a perforated pipe set in gravel, sloped so it carries water away from a problem area. It collects subsurface water, the water that has soaked in and is sitting in the soil, and moves it to a place where it can leave, like a lower part of the yard or a daylight outlet.

What it does not do is fix the reasons water arrives in the first place. A French drain will not stop a roof from dumping water beside your foundation, and it will not reshape a yard that slopes toward your house. It also is not a cure for every wet crawl space. Those problems usually need the surface water handled first, and sometimes a different system entirely.

That is why the real question is not whether French drains work, but whether your water problem is underground or on the surface. If you are leaning toward a drain, you can read more on our French drain service page.

What signs show your yard needs a French drain?

Look for these seven signs. The more of them you see, the more likely a drain is the right tool.

1. Soggy ground days after the rain stops. If an area is still squishy two or three days later while the rest of the lawn is dry, water is being held in the soil.
2. A wet spot at the bottom of a slope. Water moves downhill through soil, and it often collects where the ground flattens out.
3. Seepage or damp soil along a retaining wall. Trapped water behind a wall pushes against it and can cause problems over time.
4. Moss, or grass that thins out and yellows in one patch. Turf that struggles in one zone while the rest thrives often sits on saturated soil.
5. Footprints that fill with water. If you press into the lawn and water fills the print, the soil is saturated.
6. A spot that stays wet even with no downspout or slope nearby. That points to groundwater or a spring-fed wet area rather than runoff.
7. Previous fixes that did not work. If you already extended the downspouts and added soil but the wet spot is still there, the water is likely coming from below or from the side.

Notice that most of these involve water staying in the ground. Water that moves quickly over the top of the yard leaves different clues, such as washed-out mulch, exposed roots, or little channels cut in the soil.

Why does Middle Tennessee clay cause standing water and soggy yards?

Much of Middle Tennessee has clay-heavy soil, and in some areas bedrock sits fairly shallow. Clay holds water and lets it through slowly. When a long rain arrives, the top few inches fill up and the water has nowhere to go but sideways or back up to the surface.

New construction can add to it. Soil is often compacted when a lot is graded, and a thin layer of topsoil gets spread on top. The lawn looks fine, but the ground underneath can act like a shallow bowl. That is one reason yards in growing areas around Murfreesboro, Franklin, and Nashville can drain fine on one side of the lot and stay wet on the other.

Spring is usually when it shows up. The ground is already full from winter, and heavy storms leave standing water that can linger for days. If you only notice the problem in a dry stretch of summer, it is probably not a drainage issue at all.

When is regrading, a swale, or a downspout extension enough?

Start with the simpler fixes when the water is coming from the surface. Here is how to tell them apart.

Downspout extensions

If the wet area sits right below a gutter downspout, and it is worst during or just after rain, the roof is delivering a lot of water to one spot. Extending the downspout several feet away, or piping it underground to a lower outlet, often fixes it. A roof sheds a large volume of water in a short time, so this is one of the most common causes of a wet yard.

Regrading

If the ground slopes toward your house, or there is a low spot that holds a puddle on the surface, regrading may be all you need. The goal is to have the soil fall away from the foundation, so water leaves instead of soaking in next to it. Our Excavation work includes drainage and grading, and it is often the first thing worth checking.

Swales

A swale is a shallow, broad channel shaped into the yard to guide runoff around or away from the house. It works well when a lot of surface water crosses your property from a neighbor’s yard or a hillside. It can be planted with grass, so it looks like part of the lawn.

A French drain tends to be the answer when those steps are not enough, or when the water is seeping up from below or sitting behind a wall. In many yards the best result comes from combining them: fix the surface first, then add a drain for what remains.

How do you check drainage after a heavy rain?

The best diagnosis is free. Go outside during and after a hard rain, and watch.

• During the rain: Note where water flows across the yard, where it collects, and which downspouts are dumping close to the house. Check that gutters are not overflowing.
• One hour after: Puddles that are still there mean surface water with nowhere to go. That usually points to grading.
• Two to three days after: Walk the yard. Soft ground with no surface puddles points to soil saturation, which is where a drain may help.
• Take photos and mark spots. Use flags or stakes at the wet areas, and take pictures from a few angles so you can show a contractor.

Also note the timing. A spot that is wet only after major storms is a different problem from one that stays damp for weeks, and a contractor will want to know which you have.

What should you ask a contractor before they dig?

A good contractor walks the property first, ideally after rain, and looks at the whole picture instead of just the wet spot. Ask these questions:

• Where is the water coming from, and how do you know?
• Would regrading or downspout work solve this without a drain?
• Where will the water go once it is collected, and is that outlet on my property and away from neighbors?
• How will the trench be marked and the utilities located before digging? Calling 811 before any dig is standard practice.
• What will the yard look like afterward, and how is the lawn restored?
• Does my city or county require a permit or have rules about where drainage can discharge? This varies by location, so check with your local codes office.

If you are not sure which category your yard falls into, you can reach out through our contact page and talk through what you are seeing on your property.

Frequently asked questions