A buddy of mine is trying to determine if his foundation drain is on the outside or inside of his foundation. He has a sump pump in the basement slab with two corrugated pipes draining into it. He needs to tap into one of the pipes to provide drainage for his window well, which is below grade and prone to flooding. Question is, is it more common for the drain to be on the inside or the outside of the foundation? He said him and a buddy dug down to the footer and didn't see a pipe, but I dont believe the dug below the footer.

We bought our house two years ago. This spring, hundreds of little winged creatures invaded our living room. Creatures of the subterranean type. We did what we had to do, which included fixing the grading around the foundation. Previously the soil was up on the stucco by several inches. Now 6" of the foundation is exposed. In one particular area however, the new grading will cause a drainage issue, that I have to fix before the rainy season starts. The area of concern is the roughly 10' x 20' area, surrounded by the house on the top, the fence on the right and the walkway on the bottom and the left. See attached drawing. The mentioned area cannot be simply re-graded to be 6" below the top of the foundation. First, the area already has a slight bump in the middle. Second, I don't want to disturb the tree, the trunk of which is currently covered by soil up to several inches above the top of the foundation. Third, the walkway is slightly sloped up to the right, parts of it are actually higher than the top of the foundation. As the photos shows below, after we pulled the soil back from the foundation, there is now a trench (6" to 1' deep) right next to the foundation. My plan is to start 6" below the foundation, grade the first 1' or 2' away from the house, put in a french drain, and then come back up to the existing grade of the walkway and the tree. The red markings on the drawing above indicate the new drain. Also see section A-A for the gradings (again, new grading in red). I'd connect the french drain into the existing 4" corrugated landscape draining pipe, which is buried on the other side of the walkway. My questions: 1) Is this a reasonable plan? 2) How to drive a 4" drain pipe through under the walkway? Now, while at it, I want to fix one more thing. Some water is running off the slope (see drawing, sloped area is right of the fence). Also, the discharge line from the sump pump (also shown on the drawing) simply discharges water right next to the house, where the fence ends. These make water pool under the fence, next the house. I thought I'll end the french drain pipe with a catchbox under the sump pump discharge, this will hopefully solve the pooling problem. But it raises more questions: 3) Is it a good idea to reuse the perforated french drain pipe to carry the sump pump water away from the catchbox, or should I lay two pipes, one perforated, draining the soil, and one solid, carrying the water from the catchbox? 4) What size/type of catchbox do I use? 5) Contingency planning: if my landscape draining system clogs downstream, now a lot of water from all over the landscape will flow back through the french drain and the catchbox, right to my foundation. I assume a check valve is not the right solution, but what is? Thanks a lot in advance for all the advice! Balint [ATTACH]56927[/ATTACH] [ATTACH]56933[/ATTACH] [ATTACH]56929[/ATTACH] [ATTACH]56931[/ATTACH]