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What is a French Drain System and How Does it Work?

What is a French Drain System

Washington can be a very damp place. If you need a bit of help drying things out around your yard, you’re not alone. This is why french drains are so popular.

Do you have a permanent damp spot in your yard? Do you always get water in your basement after a heavy rain? The simple solution to help dry things up may be a french drain.

Table of Contents

  • What is a French Drain System 
  • How Does it Work?
  • Building a French Drain System
  • Contact Complete Trenchless

What is a French Drain System? 

Bob Vila tells us that french drain is essentially a ditch in the ground, inset with a perforated pipe under a layer of gravel. The pipe is very important, because it funnels storm water away from where you don’t want it. A common place to want the water diverted away from is along the foundation of the house. A french drain then deposits that water in a more desirable place, like a storm drain or even a rain barrel.

How Does it Work?

Don’t let the word “French” make you feel like this is fancy. This is nothing like a French Poodle or French toast! Think of a french drain like gutters for your yard. While gutters collect precipitation as it runs off the roof, a french drain instead manages water at the ground level. 

Let’s say that after a particularly bad rainstorm, water pools in a low spot on your property. It does this every time. Rerouting the flow of water with a french drain would alleviate this water problem.

Building a French Drain System

First, a trench is dug with a slope in the direction you want the water to go. A slope of one inch for every eight feet in length is generally recommended by experts like Bob Vila. There is a direct relationship between the diameter of a drain pipe and its relative effectiveness, so the trench should be no smaller than 12 inches wide and between 18 and 24 inches deep. 

After digging the trench, it is filled with a few inches of crushed stone. The stone is covered with water-permeable landscaping fabric to discourage any type of weed growth. Then, your crew will lay piping into the trench. Lastly, they will wrap landscaping fabric around the pipe to keep dirt and roots from obstructing the system. Finally, the last step is to infill the trench with gravel to grade. 

Contact Complete Trenchless

Don’t worry that you’ll have to figure out all of this math on your own. Washington homeowners have Complete Trenchless to rely upon!

If you feel there is an area in your yard that is too wet, too often- we can come over and take a look. It’s quite possible you need our professional crew to build a french drain system to alleviate this moisture problem. It’s nothing we cannot handle!


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