Can you use hedges or water moat as fence barrier around pool?

I have seen hedges around inground swimmingpools. The hedges would have to be the same height as a fence should be, which is 48inches. The problem would be with access. A fence has to have a self closing latchable gate...what does the Hedge row have? Not sure about the water...If someone had to enter the water to gain access to the property then it should be acceptable barrier, but that will depend on standards of insurance companty and BOCA