Issue
Courtyard seepage from a timber retaining wall is primarily caused by poor or nonexistent drainage systems behind the wall leading to water accumulation hydrostatic pressure and eventual water penetration into the adjacent area.
The property is situated on a modern subdivision and was experiencing seepage water that was accumulating in the courtyard making the entertainment area unusable. The property bordered on a steep section that was retained by a tall timber post retaining wall design.
Seepage water was flowing into the concrete courtyard from underneath the retaining wall causing water to pond and leaving muddy sediment to accumulate around the property.
Solution
The courtyard had an existing stormwater sump which was utilized to drain the seepage water. The existing concrete contours didn’t allow the seepage water to flow into the sump.
The best solution was to implement a surface Channel and Grate design with a subsoil drain to intercept the trapped seepage water and redirect it to a new stormwater sump which was hard piped to the existing sump in the middle of the courtyard.
This was achieved by ‘saw cutting’ the concrete and breaking it up and excavating a drainage trench to install the subsoil drain and Channel and Grate system.
Outcome
The seepage water that was accumulating at the bottom of the retaining wall was able to mitigate into the new subsoil drain system that was then discharged into the stormwater sump.
The added Channel and Grate also provided excess surface water to be easily managed and alleviate any concerns of any water ponding. The courtyard could now be utilized for its intended purposes.