There has been active law against the discharge of sewage from a vessel since 1972 and is actively enforced. If anyone has knowledge of anyone discharging such into public waters with 3 nm, the USCG will jump right on it and always have. Very serious fines will be imposed! All marinas must post signs stating that it is a "Closed Head Marina", meaning that your discharge valve is required to be in the off postion and locked per USCG requirements. USCG has the right to board any vessel either underway or at the dock for inspection. This feature is one of the first they will look for upon boarding of your vessel. The funny thing is though, that if you pumped out every poopie tank of every boat in the area, it would be the equivelant of 1% of the smallest reported "accidental sewage discharge" as happened at Hewletts Creek. THAT kind of discharge is what causes the problems. No telling how many of those have been unreported.