When built correctly and with quality materials, French Drains are a fantastic way to deal with a homeowners water issues.
The first step to installing a French Drain ( after figuring out where the water will end up and how much pipe you will need) is to dig the trench. A sloped trench is dug with an excavator 16” deep and 16” wide.
The trench is sloped so once the system is installed it can help the pipe do its job by bringing water to the discharge station.
What happens if the French Drain System is not Deep, Or Wide Enough
The big void space made by the rock also acts as an underground reservoir for the water entering the trench.
This is particularly helpful when there is heavy rainfall or large amounts of snow melting at once.
Backfilling The Drainage Pipe with Dirt
Why use Round Rock to Backfill A French Drain Trench
When backfilling with 1 ½” round rock, your system will have an ample amount of void space due to the size of the rock that is placed in the trench.
Void space in a trench is important, because the greater amount of void space that is in the trench, the quicker your yard will dry.
Void space allows both the surface and subsurface of your yard to dry out quickly by allowing air movement in the trench, creating an underground drying effect. The water that is on top of your yard is able to go through the round rock, and into the pipe.
Once that water gets into the pipe, the pipe can take it to its discharge station, and your yard will be dry.
Your French drain trench is what sets your entire French drain system up, so it is imperative to do this step properly ( properly excavation width and depth, and proper backfill) so that the rest of your French drain installation is successful.