Code in our town requires a fence if the pool wall is less than 48" high, ours is 52" and any structure i.e., walls, hills, fences, must be at least 48" away from the water line of the pool.

What the inspectors do is hold one end of a 48" tape measure at the waterline of the pool against the wall and swing it back ad forth, up and down. If it does not touch anything you are compliant with the code.

We layed out the retaining wall and pool so that we would have a minimum of 54" of clearance.