When filling the area around the inlet grate temporarily cover the grate to prevent any stones or soil from falling in after installing the french drain.
Installing french drain behind retaining wall.
Water that s allowed to build up behind retaining walls can damage a wall or cause it to give way.
Otherwise water moving down the hill will build up behind the wall and undermine it.
The pipe should rest on the same compacted gravel base or concrete footing that supports the wall.
Learning how to build a retaining wall can be fun with these helpful tips.
If you re building a retaining wall add a french drain behind the first course of stones or blocks.
Typically drain lines are installed at the base of new walls before the soil is backfilled.
This is so that when water gets into the space it does not become bogged down in soil but instead can flow down the wall to the drains or weep holes.
For proper drainage the first 12 inches of space behind a retaining wall should be filled with crushed stone or gravel.
Check out this video for some simple instructions on installing a french drain behind an 18 to 24 tall retaining wall before it is backfilled with dirt.