Why Did My French Drain Pop Out of the Ground?

Frost Line

• The frost line is the point in the soil that divides the soil above, which will freeze in the winter, and the soil below, which will not freeze. It is possible that if your french drain has not been installed beneath the frost line, the expanding of the frozen soil has forced the drain up out of the ground. Local municipal codes should be checked, but generally speaking, it is not necessary to install a french drain beneath the frost line unless these sorts of problems, or cracking pipes, become an issue.

Settling

• Once your french drain is installed and gravel is filled in around the pipe, the gravel will be subject to some settling. This may make it appear as though the drainpipe is rising up through the ground. If more gravel is not placed on top of the existing gravel as it settles, the drainpipe may indeed begin to rise after heavy rainfalls. Add more gravel of the same size to your drain and keep doing so until it all settles.

Backfill Material

• Using gravel or coarse sand in your french drain is of the utmost importance. You need to maintain a porous consistency to the backfill that is placed on top of the pipe to allow water to pass through freely. If you simply fill in your drain with soil, you will clog the drainpipe and may see the pipe rise and pop out of the ground. Remove the fill and use washed gravel or very coarse sand as your fill material.

Roots

• Tree roots can easily damage or force your french drain pipe up out of the ground. When installing a french drain, care should be taken to locate it far away from trees, which may have roots that would interfere with the drainpipe. If a french drain must be installed near trees, dig out around the trench and remove any roots you find. Trees use their roots to seek water, and placing a french drain anywhere in reach of a tree will mean frequent maintenance for your drain.