Solving drainage problems requires knowledge of where the water is coming from and where it can escape to. That would entail knowledge of grading of your lot and surrounding properties. You need to do some research on that and give us something to work with. Look outside the fence and see if water could be coming from those lots. Or is it coming from your lot and being blocked from escape by the wall?

THis is something that should have been addressed at the beginning of this venture . You need to provide a place for water to drain away and when you cover all the dirt with stone that does not happen, Before the garden wall there was some dirt I would guess so that is where the water used to drain . IMO you need to have the garden wall removed and find a way to isnstall some drainage.

Thanks Patricia, So definitively we didn’t get the heads up from the company that did the garden wall. We haven’t planted anything, do you think is this something they could do without removing the garden wall?