Coastal waters. In the Great Lakes area, the waters within the territorial 
jurisdiction of the United States consisting of the Great lakes, their 
connecting waters, harbors, roadsteads, and estuary-type areas such as bays, 
shallows, and marshes. In other areas, those waters, adjacent to the shorelines, 
which contain a measurable percentage of sea water, including sounds, bays, 
lagoons, bayous, ponds, and estuaries.