posted 5 years ago
Hi Yannick; Welcome to Permies!
I am far from an expert about this, but here are my observations and opinion.... for what they are worth!
From your pictures,it appears that currently all is well? No water issues with the way it is?
I see your concern that some of those stones could roll into your wall and crack it.
If it were me , I would simply fill the gap with clean washed gravel.
Do you need a water barrier between the wall and clean gravel? In my opinion, no you won't.
Rain should simply pass thru the gravel and soak in/run off the same as it is doing now.
Any of the large rocks, might start a slow creep , but will not be able to suddenly crash into the wall.
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