rScotty
Super Member
- Joined
- Apr 21, 2001
- Messages
- 9,525
- Location
- Rural mountains - Colorado
- Tractor
- Kubota M59, JD530, JD310SG. Restoring Yanmar YM165D
The whole property drops 26 inches over 330ft back to front. Ditch is about 20-ish inches deep from grade
Hmm.... Such a small slope does make it difficult; not impossible. I wonder if it is possible to deepen the ditch itself? Even a foot would help where you enter the ditch..... I assume that the house itself is in the center of the property? With that small of a drop, knowing the exact drop from somewhere within the middle of the sump pit to the bottom of the ditch is necessary since that is probably the worst case.
For very low flows to work by gravity you would prefer to have smooth wall pipe (PVC) of rather large diameter (6" to 8" probably). You might also want to do what I did - which is to put in additional covered sump pits every 50 feet or so. These I can use for inspection of the flow and also as access for cleaning each 50 feet of drain pipe if needed. And each one could have become a secondary pumping station if I had made a mistake or the pipe settled in the ground or some other unforseeable problem cropped up.
Getting the water from the sump pit to the next inspection sump pit located just past the perimeter of the foundation was the most difficult part for us. I actually ended up with of a series several connected pits under the house to get to that point and all had to be hand dug - some of it by laying in a hole - in the water - just outside the foundation and reaching by hand under the foundation.. Ugly. I hired a young guy and paid him very well for a week of that! Ours is a perimeter foundation; a slab would be more difficult. But anything can be done if you have slope.
I also "spent" a lot of my meager store of available slope in that underhouse area so that I could use smaller (2" PVC) to get the water out to the first outside pit .... which was located just past the perimeter of the foundation. Once there, things were easier. From there I could use a backhoe and larger diameter pipe. And because when digging with the hoe I could see the flow in the bottom of the ditch I was digging, maintaining the slope was much easier too.
rScotty