My toilet overflowed the other day and did much damage to a wood floor. The bath tub and shower pan were both dry. I would have thought that the overflow would have run into the tub or shower pan. Why wouldn't that have occurred.

The shower, tub and toilet all drain into a single pipe and then into a holding tank with a sewer pump. The contents of the holding tank is then pumped into a septic tank.

The tub/shower wouldn't get the overflow unless it was downstream from the
Clog. This puts the problem in your toilet bowl or the closet bend. To fix this run a closet auger down the bowl. Regards. Tom

Thanks for the response. However the reason for the flooding was that the sewer pump failed. The holding tank filled and then backed up into the toilet. Why wouldn't the water run into the tub and shower pan?

Thanks for the response. However the reason for the flooding was that the sewer pump failed. The holding tank filled and then backed up into the toilet. Why wouldn't the water run into the tub and shower pan?

To answer your question we would have to be there, check elevations, see if there were check valves on the tub and shower drains etc. I guess it will always remain one of lifes little mysterys. LOL. PS. Glad you located the problem. Tom