If you have drainage problems, digging a hole and filling it with rocks is not going to take care of it. Nothing worse than a hole filled with water, rock, and chicken poop.My thoughts are that this would improve general drainage around the coop
Better to deal with it on the surface by keeping run off water away from coop with gutters, slopes, swales, berms, etc.
Posting some pics of the area might help garner any drainage issues you have.
Apron around the outside of coop/run are the best way to deter diggers.
Good examples of anti-dig apron installation.
https://www.backyardchickens.com/threads/wire-around-coop.1110498/#post-17093528
https://www.backyardchickens.com/threads/new-coop-project.1169916/page-2#post-18481208
Oh, and..... Welcome to BYC! @IslandChickens12356
Where in this world are you located?
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Please add your general geographical location to your profile.
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