I came home for Spring Break and decided to do some work in the yard for my parents. They had an overgrown/dirt covered flagstone area that was put in a while back because the mulch that was in the area kept getting tracked into the pool.
I decided to fix this up. There was also an issue that after the pool was put in, the sidewalk was sloped towards the house, so the basement wall was leaking a bit (it's painted cinderblock, and the water was coming through the blocks and messing the paint up). So, I decided to do some grading work to fix this problem as well as aesthetically fix the area.
I created a slope away from the home with soil and away from the pool deck as well. This created a low point, which is now the problem. I realized this would be an issue, so I dug a trench about 8 inches deep along this low area and filled it with drainage gravel, just a way to get the water to a deeper soil level quickly and allow it to enter the soil (red clay) at that point. I then covered the entire area with a permeable paver base, cleaned the flagstone, placed them back in and leveled them, and top dressed with a mixture of compost and topsoil. I planted Scotch Moss on top, with the idea that it will spread and act as a live grout for the rocks. The effect was really nice, here is a photo:
Now, of course, right when we finish, a downpour starts, and it's about 15 hours later and it's still pouring. So, my drainage solution has failed, and I'm looking for solutions from you good people here. This is what it looks like after 15 hours of solid rain...
So, the drainage trench is failing miserably. By digging down say...2-3 inches to keep the slope away from the patio, I've created a low point that used to just flow into the bed on the other side of the fence and down the hill.
I can think of two solutions.
A) Re-adjust the entire slope and make it level as it was before, but then the water gathers in other spots...
B) Add a way for the water that is gathering to move through the fence and down the hill. I would assume this would involve either cutting the drainage trench through the fence and sloping it downhill until it meets the downhill slope of the yard, or adding a storm pipe that achieves this same result.
I realize I'm going to lose some, if not all of the Scotch Moss because they can't deal with waterlogged soils...which sucks but I can't really do anything about that now...
Does anyone see anything that would work better than what I have proposed? Will what I've thought of work? Are there any other underlying issues here?
I just felt like I did great work and it looked wonderful and it sucks to see it all underwater like this after all my work...of course it couldn't even wait for the plants to get established. No rain for a week, and then a downpour for hours when I finish....yay.
Thanks in advance for any help.