Retaining Wall Advice

[COpool5]

Looking into an inground pool (14x28', 4-5' deep) and the area we want it in is parallel to an existing retaining wall that probably should be replaced as part of the project. See picture (and excuse the mess in my yard) - the wall is about 2' out of the ground, and the rise between it and the top of our property is about 4'. the pool would go approx where the garden bed starts closest to the wall (so just imagine the garden bed is a 14x28 pool and yes we'd have to extend the retaining wall across the expanse of that back area). Ideally we'd put the pool long edge parallel to the retaining wall as close as possible.

Where I getting conflicting information is the following:
1 - pool builder one (fiberglass) who also does residential and commercial construction thinks the wall should be replaced well before the pool is dug with a 3' concrete footer that is allowed to cure at least 1-2 weeks before the pool project begins, and then the pool edge should be 4-5' from the retaining wall. he also thinks we need to hire an engineer.
2 - pool builder two (shotcrete) who would not do the retaining wall (need to hire it out separately), thinks the pool dig happens first and is not really concerned on the timing of the wall nor the process
3 - A well regarded landscaper said they would do a stacked stone retaining wall that is 6-8" in the ground, no concrete and has no concerns about the wall's performance with a pool edge 3' away.

Feels like everyone has completely conflicting advice. Anyone on here have any thoughts to add to the mix? Thank you!

 

[ajw22]

Do you want a retaining wall that will hold up for 10 years or 50+ years?

Pool builder one is giving you a wall that can last for 50+ years. The retaining wall will likely outlast the life of the fiberglass pool.

Pool builder two does not care about the life of the retaining wall. He build pools and the wall will be someone else's problem.

The landscape guy's stacked stone wall will probably begin shifting within 10 years and you will be rebuilding it.

You should be concerned about heavy storms and rain washing dirt over the retaining wall into the pool. That retaining wall needs to do water management of runoff and direct water away from your pool. You need good engineering, not artful landscaping.

 

[AQUA~HOLICS]

You need to hire an engineer that will specify the requirements for the wall footings and the steel requirements for the pool along with the PSI of the Shotcrete.

 

[COpool5]

thank you, appreciate the responses!

 

[.ben]

For better or worse, many PBs build gunite/shotcrete pools without an engineer (likely they “copy” a design from job to job).

Your backyard is a unique situation which warrants a specific engineered solution from a professional engineer.

I’d lean toward retaining wall first and the larger space between pool and wall, but a local engineer will help you decide.

 

[AQUA~HOLICS]

Steel Engineering firm I use will have the address of the job stamped on the plans that advise ”for use at this location” and is part of the inspection process to get the pre-Shotcrete approval.

Your backyard is a unique situation which warrants a specific engineered solution from a professional engineer

Location of the pool structure along with soil conditions for your area have a direct impact on the steel engineering requirements.

 

[TimZ]

Have you considered having a raised bond beam on that side of a shotcrete pool and using that as the retaining wall? If you're putting the pool as close as possible to the wall it might make everything look more planned out, and then it's one project.