Ideas un-clogging' return pipe?

Hello! Back after a long hiatus where I just referred to all the notes I had printed out from your forum during the first few years of pool ownership.

But the geniuses who installed our pool halfway in concrete slurry have some of the pipes running underground and some above ground. This year when we went to pour antifreeze into the water return pvc pipes, we would get about 2 cups worth in and then it would spill out. We tried using a manual "snake" to unclog it but to no avail. After much troubleshooting time and even using a hacksaw to remove a chunk of pipe that was above ground to see if we could find the problem, we gave up and figured we would just have to replace the pipe from the return area on the outside of the pool and lay the pipe above ground to the pump come spring.

It is probably a moot point now, since we do have freezing temps, but has anyone experienced this with in-ground piping? Is it likely that some pipe sections came apart underground and are filled with dirt or rodent nests? I hope we figured correctly that since we installed aquadoors on the skimmers and plugs in the return eyeballs that letting the pipes go without antifreeze wouldn't damage the pool itself -- yes?

(As I type this scenario, I realize we are the ones who sound like 'geniuses' for not asking the question when we probably could have done something about it a few weeks ago...) Should we have done anything differently and/or is there anything we should do now?

Thanks!

I'm not real clear on what the situation is -- have you not noticed your pipes being clogged, before now?

Pipes that had separated would not -- typically -- be clogged. Instead, they would 'present' as a MAJOR leak. I've seen pipes be clogged in various ways, but it depends on which pipes these are. Do they 'return' water to the pool, or bring water from the pool to the pump and filter?

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