I noticed couple of months ago that our drain in the basement smells bad. We tried to pour bleach in it an then a clear water the smell goes for a couple of hours or maybe the same day only then it comes back. What we could do with its his smell to go and never come back because it's terrible problem and it's irritating and it's not good for the health too as I have two kids wich makes me for concerned

I would advise to contact your water company and they can come out and check the drains out for you but make sure you ask them about charges before hand. It all depends on what water company you are with

Hope this helps