More information is needed to make a good guess, but you should consider a few things then you will know what to ask.
First would be when the problem first started. If only recently and you have been there for some time (several years), my guess would be it isn't groud water.
Next, Is anything different around your house that wasn't so befor the problem arose? This could mean anything from new buildings nearby, road regrading, municipal sewer/drain work, etc. .
Does the problem occur during or soon after a rainy period? Wher do your gutters drain and are those drains clogged (with leaves generally)?
I'm truly sorry that I can't be of more help,and I hope that I have help a little. Ed