Managing Constant Water Flow in a Backyard with a Rock Wall

A constant flow of water emerges from a makeshift rock wall at the base of a slope, turning the backyard into a persistent wet zone. The homeowner needs a solution that protects the house and allows children to use the yard.

Primary Solution: French Drain Behind the Wall

1. Excavate a trench along the top/back side of the rock wall.
2. Install a 4-inch perforated pipe (holes down) on a bed of gravel.
3. Wrap pipe and gravel in filter fabric to prevent silt clogging.
4. Connect to solid pipe that carries water around the yard to a suitable outlet (street, storm drain, or lower area).

Alternative: Surface Swale

If the topography allows, a grassed swale can intercept and redirect the water before it reaches the wall. This is lower cost but requires sufficient slope.

Timing Note

Since it's mid-April, some flow may be seasonal snowmelt. Monitor for a few weeks; if flow persists, install the drain.

Critical Detail

Ensure the outlet is lower than the drain inlet and that the pipe maintains a minimum 1% slope (1 ft drop per 100 ft).