I too have the same problem although I think its coming from the sump pump…no one has been able to tell me exactly what causes it.: : We have a developing septic odor problem in our walkout basement level. It comes and goes. We thought it was coming from the full bath down there and so we ran all the faucets, in an effort to eleviate a dry trap problem. It didnt work. We are having a hard time actually locating where the smell is originating. Any ideas?
