I live in a newer sub-division and my neighbors sump pump drains into a vacant feild behind my house(not his), about 15 ft outside my back property line. We had different builders and mine drains into the sewer. The problem is in the spring or after a real heavy rain, the area around the drain floods and comes into my yard about 3ft in the corner. first, is it legat to drain your pump into a vacant feaild?, and second, does he legally have to fix this problem? I am not sure who owns the property behind us ....