I purchased a home this past summer on the south shore of Long Island (south of Merrick Rd for those of you familiar with the area). I had no known issues in the basement until the heavy rains and snow we experienced this year. I was re-doing the basement anyway, so ripped up the nasty carpet and paneling that was there. I did not see any cracks in the foundation or floor, but quite a bit of effloresence on the foundation walls. It's a little hard to tell where water comes in, but it seems like it is near the seam and/or coming up from the floor. I'm pretty sure I have a high water table (there is a creak across the street and south shore LI in general has high water tables). In addition to this occassional water getting in, the humidity level down there is extremely high. I have a dehumidifier that does the job and I am amazed at how much water it sucks in, even after the summer.
There is a sump hole on the exterior of the home along that foundation wall. After inspection and concerns, I ended up replacing both the pump (with a brand new Ridgid) and the electrical outlet itself. Ironically, whenever I do get water it seems to be right in line with where this sump hole is on the outside of the home. I have tested the pump numerous times by pouring a bucket of water down there and it seems to work properly.
Not sure how to fix the problem, hoping to get some advice before getting carried away. There is a gutter drain on that side of the house that I will definitely put a concrete slab under and try and run further from the house (I do notice it pools up a bit over there). I can also do a bit of regrading, but the house overall is not at a low point, so maybe a few yards of soil right up against the house. I called in a professional who wanted to add a french drain system on the inside. That won't stop the water from getting in though, and I don't think I even get enough water to warrant the investment (not even enough to use a wet vac, a mop suffices). Aside from dealing with the grading and the gutters, I think I should dig up the pipe that runs water from the ground into the sump hole to see if it is clogged with sediment. That's a good amount of effort, so if you have any advise before I grab my shovel I'd greatly appreciate it.
Personally, I think any water is too much water. Am I just going to have to live with the fact that I get a little water sometimes? My plans for down there once I get this resolved is to add a layer of self-leveling compound followed by tiling. In all honesty that might make it high enough where I will never see water again, but not sure if I should do all that before addressing this issue.
Thanks in advance for all those with suggestions.