I am contemplating a footing drain design for our existing basement to relieve hydrostatic pressure, however the limitations I am working against include very few options for placement of the sump crock. I am considering placing the sump crock in an area that will not be at the lowest point of the basement floor, but actually, would be near the highest elevation. There is a noted difference in the floor elevation, from lowest to highest points, of about 3-1/4 inches. I am wondering if this would still work, as long as I ensure that the drain tile is sloped toward the sump crock. Would I need to consider using a deeper sump crock? I have read that the sump should be located at the lowest elevation, but our situation may not allow that to be done. How important is it for the sump to be at the lowest elevation?
Another concern I have with this is the relationship of the pipe to the footing. I don't want to slope the pipe the wrong way, if it will compromise the existing soil support of the footing. The plan is to lay the pipe along the side of the footing. I'm not sure what the actual footing height is at this point, and will not be able to determine this until I excavate. I know that I could probably get away with some difference in the relationship of the pipe slope to the footing, however I think that if there is too much difference, to the point that the pipe extends below the footing, there may be structural problems.
Can anyone with experience, give some advice on these issues?