Collapsing retaining walls despite sufficient backfill next to water

Issue description

Hello Devs,
the retaining walls collapse immediately when they come in contact with water from one side, even though there is sufficient soil support underneath them. However, this only happens in one direction (on the Armageddon map, easy starting location: the walls that have water on their right side). Walls facing the Ocean, as well as walls with water on the left side, remain stable (I have not tested the land side).

On the water side, I filled two rows outside at elevation +3 with stone and excavated down to -1 (see screenshot), so there was still a height reserve.
Greetings

Save: https://drive.google.com/file/d/1r7O05oKiCqusMrU-QAjuTWZ_HipvOspP/view?usp=drive_link

Reproduction steps

Game version and build number

v0.8.2c (b559)

Operating system

Windows

You should attach a save file.

You should attach a save file.

I tried, but zipped it is 33MB, too large. Sorry.

You should attach a save file.

I tried, but zipped it is 33MB, too large. Sorry.

Link to the cloud.

You should attach a save file.

I tried, but zipped it is 33MB, too large. Sorry.

Link to the cloud.

Of Course, didn't think about it. THX