I do some light maintenance and yard work in exchange for rent.
The building had some problems with flooding. We have an extensive drain system, but it was a bit clogged. Even after the plumbers unclogged the drain the owner of the property is having a sump pump plus a curtain drain installed.
We have had some dispute about covering/back filling the curtain drain. The contractor is against it. I don't want to insult the contractor or the owner of the property. As the contractor is a friend of the owners. The owner of the property is a very intelligent woman, and if a logical argument is made will likely reconsider. Should a proper curtain drain be covered/back filled or should we really leave a gravel trench in the middle of a yard? I have spent a little bit of time researching curtain drains, and most instructions indicate that the last step is to landscaping fabric, and few inches of soil and some grass. While this will certainly make mowing and autumn leaf removal a pain, I also generally care about the appearance of the property and this decision seems wrong.
the question: to cover/backfill with soil and plant grass or not to cover/backfill a curtain drain
Best Answer
The usual purpose of a curtain drain is to divert (under)groundwater away from a structure. The only reason to not cover it with fabric and a few inches of soil is to capture surface drainage as well. If you need to capture surface drainage, then there must be a significant grading issue that is allowing surface water to stand near the structure.
Such a grading issue should be corrected, in which case the curtain drain could be covered. If for some reason it cannot be corrected, (or this is actually a gravel filled trench drain) then the gravel should be left exposed. It will also need to be maintained so that it does not get clogged with silt and other material carried in surface runoff.
In summary, the proper surface treatment depends on the intended purpose(s) of the drain.