 So I would take a very careful look at that hose valve and make sure, or really any other place on the hose, sometimes when you have sections of hose that come together, it can be leaking from those sections which are just not noticing it. Make sure that when you open up that hose valve on the outside that there's no other water coming out except through the end of the hose where it should be coming out. Because I suspect that there's some leakage there and it's getting into the ground and that's what's showing up in the basement as a leak.