I don't believe there is any restriction. Back when I first started going to Bay Creek the farthest South I've seen a boat was a section of the creek below Tryon Park. Beyond there, the creek alternates between slow deep moving water and fast shallow water. There used to be an artificial mini-dam sluice at that point preventing larger boats from going further north. That has been removed, slowing the overall flow and allowing a lowering of water south of that point. The gate was essentially at the interface between marsh and light woodland sections of the creek.
I have never seen one due the quantity of kayaking and fishing in the narrow chanel. I would check with park services to be on the safe side.
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