More about the Point Pleasant canal: it is a 1.9 statute-mile-long canal connecting the Manasquan River (and Manasquan Inlet) with the northern end of Barnegat Bay in New Jersey. It is an integral part of the Intracoastal Waterway. The 9-knot figure for maximum currents comes from the NYNEX Boaters Directory/New Jersey Harbors cruising guide. Some insight into conditions on the canal can be gotten at www.thehulltruth.com/northeast/99232-point-pleasant-canal.html I could well be wrong, but I'm guessing that there may even be places in Washington with similar conditions: massive powerboat traffic, narrow confining bulkheaded margins, swift currents, chaotic boat wakes.......