The Lane Cove River where I moor, an extension of the Harbor, has "Reduced Wake Zones" along it. It is lined with expensive houses both sides, many with jetties and or poles for boats. It is also infested in summer with water skiers, whose reason for being involves creating as much wake as possible, as deep as possible, as fast as possible, plus breaking the rules on towing distances off objects, observers, etc. There is no speed limit, 8kts would probably work. I keep speed down to avoid wake, the sign says to, people live there,some have little beaches, even haulout facilities, lots of boats are on moorings, people go fishing, kayaking, sailing and racing in dinghies,even proper rowing with 8s and other shells.
I suggested to "Roads & Maritime" they either implement a speed limit(which would cure both wake and infestation), or I`d regard it as ok to power up and put out lots of wake. My email was lost for 3 months,(they were about as keen to pick it up as a poisonous black snake) then the local BSO (Boating Service officer) got in touch, decided no action was warranted except to better police the ski boats more, which he has. I still don`t power up, and put up with the ski people, partly for fear of having my boat vandalized later if I take them on. Co-existence I guess, not on my terms.