We have a newer home (7 year old.) We just discovered probably a gallon or two's worth of water and black slimy sludge in our utility room. It seems to be centered around our floor drain, but it is kind of hard to tell. It does not smell bad per se - maybe a little greasy or medal-y. We are at a loss - any ideas what this might be?

Most likely, you will need to snake you main sewer line. The black residue is what's left from sewage overflow pushed out from your floor drain. Take care of it in timely manner as this kind of problems don't go away on its own.

If you are handy and not afraid to get dirty, you can do it yourself - or call local sewer cleaning contractor to do it for you.

Let me know if you need help guiding you through snake rental and drain cleaning procedure.

Back to you. Milo