On Sunday, March 26, 2017 at 12:11:55 PM UTC-4, HerHusband wrote:
I just bought an old farmhouse (really good deal) an am going through
all the repairs that need to be done and now have a puzzle.
When a large amount of water is flushed down the pipes (i.e. bathtub
emptying) the basement fills with sewer gas. Found a clean-out cover
rusted out (and now fixed) but still having the gas odor.
I think that when the waste water enters the tank, the gas gets pushed
back. After the fix it has dropped noticeably, but it appears it has
now been directed to the tank vent.
There's still some gas in the basement, and a fairly good stench from
the septic vent, have I been living in the city so long to forget that
this is normal?

What do you mean by the "septic vent"? Normally, your main drain line
should have a vent pipe that runs all the way up to the roof.


Older homes I've seen here, built 1950 and earlier, don't have
a main vent that runs out the roof. They have one on the
sewer line, near ground level, where it exits the house. Then
they have vents for bathrooms and such that do extend out
the roof.