We live in California and this past year, after 6-7 years of drought, we got 40 inches of rain (which is double the amount of rainfall in a normal year), and we had water in the crawlspace under our house. It was never more than maybe a quarter of an inch in some puddle areas, but the ground in some spots was “soupy” like if you’re walking on a beach after a wave goes out. We have very clayey soils in our area and live near a lake.
I spoke with neighbors and they indicated that all of the houses in our area get some water every 7-8 years in times of excessive rain - no one seems to be worried about this but me. I should mention our crawl space is about 5 feet high in some areas, which maybe should have been an indication to us of an issue in retrospect, but we’re on a partial hillside so it just seemed like that was how the house was designed. Our house is nearly 50 years old so if water is an ongoing issue, it hasn’t affected the structural integrity at this point.
Anyway, I had an engineer come out, who said, “this is nothing, you should see other homes in the area” (!) but recommended we put in french drains along the front and back of our house, which we did (fairly huge expense). However, there are still areas that are soupy now – three weeks after the last rainfall. Either there is still just a ton of water in the soils under the house that is making its way out, or the water table (which apparently has risen 50 feet this year) is still high. At the recommendation of the landscaper who did the french drains, we dug a sump pit a couple of weeks ago. Overall the water level is slowly dropping in the pit, but the pit always has water in it. The minute it empties it starts filling again. I think this means the water table is still very high.
My question is - assuming the water table is always there, should we stop pumping? Should we fill in the pit at some point (the water now starts about a foot below ground level) so that the water can just flow downhill under the ground? My son who is in to physics mentioned something about the pump possibly being a “siphon” which would attract water to the pit at all times. I’m not sure we want this forever. Any thoughts? Thank you!
Around here the general consensus is that if the hole never goes dry you’re creating a good path for water to flow toward your house, while if it does go dry the the water may go somewhere else. Since the flow of water underground is highly unpredictable I don’t if that is really true or just coincidental observations.
I’m not sure what you are considering, without a pump you can end up with a lot of standing water. I’m going through this right now with an addition to my house being built. The water table rises here in the winter and spring and I’ve been pumping constantly since December to try to get an idea where the water table is. There’s a deep hole that goes down about three feet below the floor that water continues to enter, but more slowly as each day goes by. I expect it to be dry by the end of June. What happens next winter is a mystery, after years of pumping the water level in the main house has gone down considerably and remains nearly dry except after major storms or snow melts, hopefully in the new part that will happen eventually.
If you dig a pit and it keeps self filling, for the most part, i would say the ground water level or saturation is high. (Hard to say which, i cant physically see your landscape)
Be very hard to change that on a localized basis.
French drains dont do a whole lot when the entire area is saturated.
If it’s only a once per 7 year thing, and your foundation is in no danger, sounds like something you simply deal with?
Kind of sounds like living in florida.
Thristy? go dig a hole in the ground and wait a minute
Thanks for the feedback. Yes, this year was exceptional in terms of our rainfall – the most ever on record. I guess we should wait until next year and see what happens, but I’m just hoping we’re not “pulling” water up from further down.
Spouse has convinced me to stop worrying about this and wait until later in the summer to see where we are. 
I think the question here is what kind of foundation do you have, on what kind of ground. The local standare here would say if your foundation has footers (or 1 foot thick walls), and the ground underneath is stable, and the water level is one foot below the footers for most of the year, then you aren’t gaining anything by constant pumping. If the water level gets higher during part of the year you can just raise the pump or adjust the float valve depending on the type of pump so you aren’t pumping all the time. If it’s a submersible pump it will stop pumping all on it’s own before long anyway.