We’ve had to have the RotoRooter guys out twice so far this year, so we took their advice and arranged to have a team come out, excavate a possible blockage in the line and do a “spot repair.” They arrived about 10:30 this morning.
Five and a half hours later, we all know a lot about our sanitary plumbing that we didn’t know before. The house is 100 years old, and it turns out that the sewer main and its associated inputs are also about 100 years old, and the main line is clay pipe. We’ve also discovered three sewer cleanout openings we didn’t know we had, one of which had a lower cleanout lid leading to a flapper valve (meant to prevent backflow from the street into our yard, which is slightly lower than the line in the street).
The expert they sent out (a very experienced supervisor) believes all our backup problems relate to the flapper valve, which had rotted away from its attachment and was rolling around loose on the floor of the main pipe. The expert was quite surprised to find this valve in our parking strip, next to the street; he said they’re usually placed right near the house. But there it is, and they had to dig up about 4 inches of dirt and several Algerian iris plants to expose the cleanout lid.
The good news is that, although there are some minor issues with the main pipe, the flow to the street from the house is unobstructed and the clay pipe is generally intact. Now that they’ve removed the loose flapper, he thinks we should have no more backup issues. The area where we thought we had a blockage turned out to be a junction with a former storm drain, which was patched into the main sewer many years ago, and was closed off and capped by our neighbors more recently, when they redid their own plumbing. So we don’t need anything more now except putting everything back together, re-laying the concrete they dug up beside the house (where the old storm drain was), and leaving all the cleanouts accessible.
And this is a good thing, because if we ever do decide to do a trenchless sewer main replacement, it will require digging up the street out near the main (an Oakland city requirement) at our expense. With traffic management, and repairs to the street. And that will cost us somewhere in low five figures. I asked why they have to dig up the road if the replacement is “trenchless,” and they pointed out that they have to be able to get at all the ends of the line.
If we ever sell the house, we’ll have to do it, because of the local requirement, imposed by the local water company shortly after the major remodel we did in 2012! If we tried to do that remodel now, we’d also have to do the sewer line replacement. Since we don’t plan to move out any time soon, we’ll worry about that later.