If there are no sewer gases coming from it now, then most likely it is not tied into your sewer system or it already has a pee trap. I am not a plumber but most of the floor drains I have seen do not drain into the sewer system. They merely seep into the ground. Use a hose and try to run about 3 GPM into the floor drain for about 15 minutes. If it keeps up with the flow, you could use it for a softener drain. I don't think it will.