I think the squirrel had been drinking from the horse tank in the past and we usually kept it pretty full so for whatever reason, the heat maybe, the water level was low and when she fell in it was too low for her to get out. Thank goodness I went out that day and heard her splashing around.
Your use of the hoe was timely. Last year I was trapping squirrels to stop the midnight basketball games they were playing in out attic. One male was particularly aggressive and got out of the trap that was on the back porch prior to my relocating him to another habitat. Anyway, he was going berserk running up and down the screens. I didn’t want to shoot him and I didn’t want to get anywhere near those teeth so I used some bacon tongs to grab that hyper rodent and put back in the trap. That took several attempts and he did manage to scratch me, but he is now enjoying life in a park across town (maybe).