replying to SoloMan, soloman wrote:
Now that I am thinking about it, for the past few months, occasionally
there would be a smell in the downstairs level of my home. I tended to
think that it came from the bathroom and/or shower drain. The same drain
that backed up last week.

There is a P trap in there and I would run the water weekly just to make
sure it was filled. But perhaps the plumbing was "slightly" backing up
causing there to be a slight mixture of sewage water in the P trap of that
shower? It definitely never came up through the drain before, but there
was definitely a smell. I remember pouring some bleech down that drain a
few months ago because of the smell. And I remember smelling a smell
Wednesday night, the night before the sewage started backing up through
the drain.

Perhaps this issue was coming for awhile now and finally reached the point
of no return last week.

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