Laurie wrote:

Mystery of the day. I was sitting at my desk at home when all of a sudden I
heard the toilet flush - but I was the only one home. Checked the toilet -
no water. Checked the tub - evidence of backup already subsided. Flushed the
commode. Flushed fine, filled fine. Went to back bathroom - same thing.
Flushed that commode - all's well. There was a strong sewer gas smell in the
back of the house. Also noticed water on front porch that appeared to
emanate from drain cleanouts.

Called city water department - nothing going on in this area. Two days ago
we had a day of very heavy rains. I was also doing a load of laundry, but am
pretty sure it was already done when this happened.

Can anyone tell me what has happened? Should I be concerned (other than to
disinfect said tubs?)? Should I take any action (like call a plumber?).

TIA, Laurie


Total guesswork without seeing the actual layout.

My guess: The storm runoff flooded the city sewer system,
causing it to backup into your (and others) sewer lateral
connection.

Either the sewer venting on your house is not working or
(more likely) the flooding rose to a level high enough
so as to block off the vent. As the water rapidly receded,
the force sucked all the water out of the toilet traps
(because the vent was unable to prevent the suction).

Ask around the neighborhood at similar homes at the
same elevation to see if anyone else experienced it.

It's probably a municipal issue and not something
a plumber will be able to do much about.

Jim