Tips For Installing A French Drain System In Your Yard.
A properly installed French Drain System can improve your yard for years to come.
Steps to Install a French Drain:
Identify the Water Source:
Start by identifying the water source and find a place to divert the water to.
Note: Sometimes there is more than one source of water, which can't be identified until the drains are installed and begin working.
Plan for Additional Drains:
You can always add drains later to improve any remaining problem areas.
Check for Utilities:
Before you begin digging, always have the area checked for utilities.
Excavation Process:
Once the area has been checked and marked, you're ready to start digging.
A mini excavator is the best option for excavating the trenches.
Avoid using a trencher with a 6-inch cut; it won't provide a wide enough trench for a long-lasting drainage system.
A 9-inch to 18-inch wide bucket is sufficient.
Trench Depth: The depth will depend on the elevations of your yard, aiming for a minimum slope of 1% (1/8 inch per foot). If more slope is achievable, that's even better.
Installing the Fabric:
Install a permeable non-woven drainage fabric in the trenches.
It's crucial to use the correct fabric; avoid woven landscape fabric, as it won't let water through efficiently.
The purpose of the fabric is to separate the soil from the stone and pipe of your drainage system.
We have replaced many failed systems built without fabric, where the soil eventually migrated into the stone and clogged the system, causing it to fail.
Pipe Installation:
Once the fabric is in place, install the pipe directly on the bottom of the trench.
For most applications, use heavy-duty, 4-inch perforated corrugated pipe made of non-recycled materials.
If needed, more than one pipe can be used in a trench. A 4-inch perforated pipe can move up to 240 gallons per minute.
Secure Connections: All pipe fittings should be secured with tile tape to ensure the connections won't come apart.
Backfilling the Trench:
The trenches are then backfilled with #2 river rock (round rock).
Why River Rock? River rock is chosen over limestone because it does not compact, unlike angular limestone, which will compact.
River rock creates more voids, giving the water an easier path out of your yard.
Be sure to hold the pipe down during the backfill process.
Final Steps:
Backfill the trench to approximately 6 inches below ground level, leaving room for topsoil after the fabric is wrapped.
The fabric is then tightly wrapped over the river rock and pinned.
Trim the excess fabric, leaving no more than 2 inches of overlap whenever possible.
Once the fabric is wrapped, place several inches of topsoil on top of the fabric, and plant grass seed.
Important: The wet soil/clay excavated from the trenches should never be placed back on top of the trenches. It's best to haul it away or completely remove it from the yard.
Additional Considerations:
Primary Use: French Drain systems are primarily used to divert subsurface water.
Surface Water: Yard drain catch basins may also be needed to quickly remove surface water from low-lying areas.
Grading: Grading can sometimes solve surface water problems as well.
I hope that you found this information useful.
Feel free to leave us a comment or question below.
CTX Excavating LLC services Butler County, PA and northern Allegheny County, PA.
Call us today for a free estimate. 724-991-1865
