I have a 50s built home. The outside sewer line does not have a cap. Instead there is a small hole in the line with a concrete slab laying over the pipe. I recently unclogged the line and now the cover does not keep the water running out. I've lived at the house for ten years without a problem with pipe cover.

The way the cleanout hole was done is kinda rigged, why not dig it out a little and put in the proper fitting, run the cleanout access up to ground level and cap it properly? The way it is now, with any problem downstream from the patch you can have a smelly overflow. And you probably didn't get the line completely clear if the water is backing up and flowing out the hole in the pipe (unless the drain line is undersized or sloped wrong). To be fair, it being wrong for 10 years without a problem doesn't make it right.

Or you can put a piece of curved plastic over the hole and duct tape tightly around the pipe, might last for a while.

[edited to remove mild swear words and spelling errors]



Edited 7 times.