Answer: Based on your description I can think of several possible sources for the water. One is a natural spring. If that is what it is, you might be able to have it capped and control the water that way. A well digging company might be able to help you with that. But if the moisture is there, you will need to direct it or control it in a way that does not cause new problems. Another possibility, although I am sure you have thought of it, is that the pool is leaking slowly and saturating the area. Another possibility is that a drain field for a septic system or a French drain (such as from underground gutters) or the outlet from a sump pump is located in that area. Sometimes the sump pump outlet becomes covered over after many years and nobody realizes or remembers that it is located in a certain spot. I think you still need to identify the source of the moisture before deciding how to control it. Once you know the source, you could consult with your county extension as to how to proceed. In the meantime, perhaps you can fence that area off to keep the dogs out of it and/or train them to wipe their feet (many dogs will do this) before allowing them in the house. I hope this gives you some ideas.
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