Waals Coppasing

Issue description

Hi! One of the wall "directions" are bigged, as soon as I excavate to the bottom of the wall (5 levels down - to where you can see the chevron markings) one direction of retaining walls colapses. All three the other directions are fine.

Reproduction steps

Pretty much....

1. build retaining wall
2. Designate mining area
3. Wall colapses as soon as excavotor starts digging.

First noticed this in ocean tiles using amphibious vehicles to remove overspill on the ocean side, all aother waals are fine just 1 direction has the issue. Though it may just be becase of the ocean...bit no, this seems to be an issue after the new patch, in the picture you can see the pre patch wall holding. Only the lower wall is colappsing.

Game version and build number

v0.8.3 b575

Operating system

Windows

Attachments

your walls are too high when the red warning marker shows they are about to collapse. Dig one level less or lower the wall 1 level

You are indeed correct in the above case (I'm an idiot for not noticing this, I have many hours in game...), but it remains a problem here, or is this just intended behaviour, I am trying to create sea walls, you can see in the screenshot that is provided here ... Mining designation height are the same for both walls as is terrain height. Yet the while one wall holds...the other collapses immediately, it is not even necessary to dig to the depth specified before this happens....

I have tried going one level up as well to -2, but this remains the case. All three other directions are fine...