What is a French Drain?

Looking into a French drain covered in rock

A French drain won’t turn your landscape into Paris, but it will keep it from turning into a lake. Just like your gutters ferry water off your roof, French drains carry it off your property on the ground. 

If your morning stroll involves squishing puddles or a valley in your yard keeps collecting rain, a French drain might be the solution for you. This drainage solution is aesthetically pleasing and great for mildly sloped yards.

How does a French drain work?

A French drain is a fairly simple system for redirecting water away from unwanted collection points. It uses gravity to carry rainfall away from your lawn and down a pipe placed in a slightly sloped trench toward a suitable exit point. 

What are suitable exit points? 

  • Municipal storm drain
  • Rain barrel
  • NOT your neighbor’s yard

A French drain is an underground drainage system because it takes surface water like sprinkler runoff underground to drain it into the soil and carry the remaining water to an exit point.

How to build a French drain

You can get a French drain professionally installed or do it yourself. 

There are four main components of a traditional French drain: 

  • A trench
  • A perforated pipe
  • Landscaping fabric 
  • Gravel

The pipe with holes at the bottom is laid into a ditch in the ground (usually 1-2 feet deep). Landscape fabric lines the pipe and gravel goes on top until the depression is level with the rest of the ground. The landscaping fabric prevents soil and roots from clogging the perforated pipe, and it stops the gravel from traveling along with the water.

French drains need regular maintenance because they’re at risk for clogs. If they’re anywhere near downspouts, add a leaf screen to the French drain pipe for additional protection. They usually last eight to 10 years before they need repairs or replacement.

Different types of French drains

You won’t encounter a lot of different types of French drains. The traditional drain is like we described above: a pipe is laid in a trench and carries water from an undesired location to an exit point.

You also may find a combination of an area drain and a French drain called a modified French drain. This system involves a shallower trench with rock or gravel filler placed all the way to the surface. 

Indoor French drains, also called a weeping tile, drain tile, perimeter drain, or subsurface drain, are available as well. These are installed directly in your basement to redirect water away from your home’s foundation.

Pros and cons of French drains

A French drain is a great solution for some homes, but it has drawbacks, too. Take a look at the pros and cons to help you make your decision, and see a full list of benefits of French drains here.

Pros

✓ Prevents standing water
✓ Aesthetically pleasing drainage solution
✓ They’re durable and can last up to 10 years without repairs
✓ Quick and easy installation
✓ Erosion control
✓ Reduces toxic rainwater runoff

Cons

✗ Digging underground runs the risk of hitting utility lines
✗ They can become clogged without regular maintenance 
✗ Not suitable for properties situated at the bottom of a slope (unless you also install a sump pump)
✗ Requires strong rainfall to carry water successfully to the exit point – not suitable for surface water like sprinkler runoff

FAQ about French drains

1. How do I know I need a French drain?

The first sign you need a new drainage solution is standing water in your yard. Does your lawn feel squishy the day after watering? Are there puddles on the ground or runoff on the driveways or sidewalks? Damage to your home’s foundation or basement is also a sign of a drainage issue. 

French drains work best for properties that have a slope of less than 1.5 inches. If you have a steep slope, opt for a surface drainage system. In this case, French drains can result in water seeping below your home.

2. What are the alternatives to French drains?

There are certainly alternatives if a French drain isn’t suitable for your property. A few options are:

Channel drain: A channel drain (also called a trench drain) usually involves a grate that drains water along the entire length. This is an above-ground drainage system. 
Catch basin: A catch basin is essentially a storm drain that collects water in an underground tank, which is then directed toward a sump, municipal water treatment service, or alternative reservoir. 
Rain garden: A rain garden is a more botanical drainage solution. It’s a collection of water-loving plants installed in a low-slope area. The roots use pooling rainfall, preventing water from sitting at the surface.

3. How much does a French drain cost?

The average French drain costs $4,500 for professional installation. The cost varies depending on the length of the drain — expect to spend $10 to $100 per linear foot to install a French drain.

4. Can I install a French drain myself?

The short answer is yes, if you’re experienced with home repairs, you can take on French drain installation. The most difficult part will be digging the trench — it’s important for safety to have an idea of where electrical lines might be before you start. 

If you’re not interested in breaking out your shovel, contact a professional landscaping team to install a French drain for you. For all your other lawn maintenance needs, including cleaning gutters and downspouts, mowing, and seasonal cleanup, call a Lawn Love pro.

Main Photo Credit: Shutterstock

Rachel Abrams

Born and raised in Gainesville, Florida, Rachel Abrams studied creative writing at the University of Virginia. She enjoys volunteering at her neighborhood community garden and growing herbs in her New York City apartment.