We still get asked to bury a French drain on a Mt. Lebanon clay lot with no answer for where the pipe finishes. Clay does not swallow the last inch. If the outlet is the neighbor's yard, the alley, or a low spot that already ponds, we bought a wet trench with a pretty grate.
Eichenlaub will not dig that pipe until the finish is legal and dry. Design and build start with the outlet, not with the catalog drain.
Name the finish before you name the pipe
Stand outside after a gully washer. Watch roof water, the garage apron, and the side yard. South Hills lots often sheet toward a tight property line. A pipe that ends at that line is a lawsuit with extra steps. Borough rules still apply. You cannot improve your patio by making their basement the outlet.
Photograph the puddle, the downspouts, and the fence. Write how long water stays. A dry well in saturated Pittsburgh clay fills and stays full. That is not a finish. A pop-up in a place that already sheds can be. A connection that the borough will not allow is not a plan we will draw.
Clay hillsides lie to a short trench
A French drain on a slope can work if it has fall and a place to daylight that is still on your lot or in an approved system. A flat trench behind a new patio on fill is a bathtub. We have opened those in year two. The stone is wet. The pipe is a souvenir.
Check irrigation overlap. A zone that soaks the same corner every morning will look like a drainage failure. Pair any drain with maintenance that does not bury the outlet in mulch the first spring.
Hardscape that already sheds is an asset. Do not rebuild a walk that worked in order to hide a pipe that has nowhere to go. See the Outdoor Living Studio when the patio itself is the dam. That is a grade conversation, not a sock-pipe conversation.
Keep the neighbor and the street out of the scope
Moving water onto a township inlet you do not have permission to use is not success. Moving it onto a hillside that already slumps is worse. If the real problem is street grade or a shared alley, we will say so. A bed drain will not fix that.
Mt. Lebanon, Upper St. Clair, and Fox Chapel lots all hit this limit in different ways. The clay is the constant. The legal finish is the variable.
Write the outlet on the drawing
Before we trench, we want the outlet, the fall, and restoration on your lot only. If we see a separate foundation issue, it is its own line. Call (412) 767-4769 or contact us with storm photos. More notes live in our articles.