planning to remodel. every once in a while, I read in the local paper about sewer lines backing up into residences and the mess it causes. and, by definition, the blockage is somewhere downstream that must be found before the mess stops itself in the upstream service taps. furthermore, the homeowner is left to himself and the damages.
question: is there a backflow preventer that can be installed on a 4″ sewer line? or any other way to adress this stinky (allbeit unlikely) problem?
thanks in advance
Replies
Yes there are backflow preventers that go in 4" PVC sewer lines for the reason you cite. Locally they are not required unless the subject house's first floor level (assuming no basement fixtures) is not a certain number of feet above the nearest, downstream sanitary sewer manhole cover. I'd say this situation is what resulted in the situations you read about.
A little trick is that you leave the cap in the yard for the sewer cleanout for your soil line just barely threaded on - that way, if there is a backup and any pressure at all, the cap just blows off and your yard gets fertilized - not your house.
Dirishinme's advice is particularly valuable. Having the soil line cleanout cap just barely engaged, keeping in mind you don't want your lawn soil to seep in there either, will provide the needed weak link outlet. When your neighbour's basements fill with sewage and yours doesn't, you'll know it is time to shovel your way down through your lawn to reset the cleanout cap.
Get the best quality backflow preventer you can, and install it as securely as possible. A municipal backflow builds a big head of sewage ... you don't want the preventer blown off the drain...
Edited 12/26/2004 3:36 pm ET by Pierre1