How to set your expectations for your French Drain system

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Picture of Natasha Maerz

Natasha Maerz

Owner/Office Manager

When thinking about what your budget is going to be for a drainage system, you might be surprised that your expectations set what kind of French Drain system you get, and sets what your budget should be. French drain systems are a great way to make your unusable yard usable again, and fix drainage issues, but not all systems are created equally.

When people start thinking about getting a French Drain installed, it is because they realize that their yard is unusable, and stays a soggy mess. Figuring out what your expectations for your French Drain system will help you determine what type of French Drain installation works for you, and your budget.

What determines how dry your yard will be are three things

The type of soil you have

If you have sandy soil in your yard, you most likely are not concerned about getting a French drain installed. Sandy soil allows surface water to penetrate into the ground, and takes excess water away from your yard. Therefore, you will not have pooling of water and will not need to fix any drainage issues. Lucky you!

If you have clay soil, the opposite is happening to your lawn. Water cannot penetrate through clay soil, so it sits as surface water on top of your lawn instead. This causes a soggy, muddy, backyard and landscape. Between children and pets with muddy wet feet running in and out of your house, and canceled BBQ’s, water issues are extremely frustrating, and can cause some major stress.

The health of your lawn

Another factor in how dry your yard will be is how healthy your grass is. Healthy grass roots, plants and vegetation are what help the surface water pass through the clay soil in your yard and into your system. Without an abundance of roots penetrating deep into the clay soil, water will sit on top of the lawn regardless of any drainage system that is put in. The roots from your lawn, and plants, play a vital role in allowing this water to follow the roots deep underground and into your French Drain.

The amount of pipe that is placed in your yard (the French Drain System)

The layout (and amount) of the drainage pipe placed in your yard is important because the pipe that is in the ground absorbs surface and subsurface groundwater, and makes it disappear to the designated area. The more collected water that gets into your system, the dryer your yard will be. This means that the more drainage  pipe that is placed in your yard, the better the drainage system. The best layout is different for each yard and landscape.

So, how does budget affect how dry a yard will be?

As stated above, clay soil is one of the major causes to a yard needing a French Drain. To get a yard that is completely dry, clay soil needs to be removed, and replaced with sandy soil. This option is definitely an investment. Excavating 4” of soil from your entire yard can take a long time, depending on how large your yard is, and hauling soil off site gets pricy, especially when you take into consideration that soil expands 1.3x its size when excavated! Replacing the excavated soil with sandy soil takes time, and again, hauling costs.

If removing your clay soil is not an endeavour you want to take on, you can focus on the amount of pipe that is placed in your yard. Simply put, the more drainage pipe you have in your yard, the faster the water will get to its discharge station. The more pipe you have, the more labor and material costs there will be. To give an example, 100 ft of pipe will cost around $5,000, while 1000 ft of pipe will cost roughly $41,000. That is a huge cost difference, and is going to be based on how big your yard is, and how serious you are about fixing your drainage problems.

Healthy grass is something that takes time, effort, and ample watering, but is something that should not be overlooked if you are truly wanting to fix your water issues. Even a yard with the biggest/best system will benefit for healthy grass. The cost of keeping your grass healthy will depend on what type of grass you have in the first place ( is it fairly healthy, patchy, or non-existent), and how you are going to maintain it. If your grass is already established, the cost of getting your lawn healthy is nothing compared to the benefits you will see when you are able to fully enjoy and use your yard.

When having a French Drain system installed, take the time to really think about what you want the outcome of your yard to be after the project is over. Consider all of the factors (lawn health, soil, and amount of pipe) and really think about how you use your yard, and if you value useable lawn space. Not only will a dry lawn make your yard more enjoyable for everyone, but it will add value to your home.

Curious about the problems with French drains? Read 6 drainage problems you may have and not know about.