My house is built on sandstone. We are high up on the Sydney, Australia coastline 500m from the sea. Fresh water is percolating through the rock under my place. Have removed all rubble & wet sand from under floorboards & am left with three big underfloor puddles on the high side of the house that find their own level & stay there regardless of amount of rain. Lots of houses in this area have the same problem & water seeps down cliffs & pathways. To install a pump inside under new flooring? dig pit outside with ballcock & pump? put down barrier? move house? If anybody has had this problem, I'd love to hear from them.