I purchased my first house (on city water and sewage system) about 6 months ago and the main sewer drain clogged and backed up through the basement drain within the first week being there. We're talking a couple of showers and some typical toilet use. Plumber used a rooter to clean it and I haven't had a problem since. He showed me using the camera a small dip in the cast iron pipe where he believes the clog was, but other than the pipes being old (house 1963) he says they still have life left. No roots found, and I believe he checked all the way to the end of the pipe (to the street).
My question is: why did they clog for me and not for the previous owners of 30 years (assuming they are being truthful and also based on the rusted shut clean-out access point). Not knowing if/when the pipe is going to back up again still keeps me up at night.
Possible reasons I could come up with:
- The house was sitting unused (how long I am not sure, 1 week if I had to guess) which gave time for gunk to solidify in the slight dip
- Something crawled up the sewer and died in the slight dip
- I introduced something large enough to block the sewer, but I am very aware of what I would put down the drain
The blockage was in a section of the pipe still under the house, maybe 20ft from the clean out access point.
Any thoughts whatsoever appreciated.