CASE STUDY – from the files of Integral…………
When we attended the site, the weather was overcast and raining adding to the heavy rain from the night before. The ground and lawn along the north fence line was saturated and wet with standing water. This condition can and has caused erosion, and can weaken the fence posts, etc. It was also observed that the neighboring property, was much lower and had constructed a retaining wall along the fence line on their property.
The natural run off water is toward the north and east which would account for all the water on the north side of the property line. There have been some attempts at one time to deal with this water because there are catch basins along the property at different intervals.
They are ineffective because:
- They are installed too high (above ground level).
- They are not perforated to allow water to enter below the surface.
- The lawn is not graded correctly for this type of drainage.
The north fence also has soil, mulch, and vegetation against the bottom of it which will shorten its life expectancy by causing rot. The fence needs to be realigned and it should also be raised to allow air to circulate.
The retaining wall on the neighbouring property should have had a drainage system installed on the south side of the wall or drainage ports installed to allow the ground water that can be trapped behind the wall to escape. We cannot verify the construction of that retaining wall; however all the symptoms of a drainage problem exist on the surface of the subject property that lead us to suspect that this is what is causing the problems. An engineering report would have to be obtained to verify this conclusion.
The solution would be to install a drainage system next to the fence on the subject property side along the perimeter to the rear fence line and then take it along the rear fence line to the storm drain at the end of the pavement in the parking area. In fact, the parking area should have the drain moved to the center and the asphalt graded so that the area drains towards the catch basin. This would also resolve the problem in a previous report concerning a neighboring tree with roots extending into the parking area. The drainage system can be done at the same time the fence is removed and realigned due to the narrow passage ways between the patio fencing and the north fence.
The adage “you can pay me now or pay me later” sure applies here. The cost to add drainage at inception would have been less than $5,000, but now putting in the drainage system along with remedial repairs cost more than $50,000.