Lock and Bridge Etiquette

Lock and bridge etiquette makes a day aboard safer.

January 12, 2011

A cloud of smoke hung in the lock, thickening until the acrid taste filled our mouths. Our ears came under assault as the gate closed and the water level dropped, transforming the lock into an echo chamber that amplified the rumble accompanying the smoke. Despite pleas from other boaters transiting Long Island’s Shinnecock Canal on that summer Saturday, the skipper of the offending boat refused to kill his idling motors.

Courtesy on the water means more than just throwing the obligatory wave. It’s the backbone of safe operation in the close quarters of locks and bridges.

Kill ‘Em
Exhaust fumes are heavier than air, building up within the confines of a lock before sinking in a toxic cloud atop other boats as the water level drops. So shut the engines off, even if you’re just locking-through for a few minutes.


Most boat engines idle at about 62 decibels (db-A), according to Boating’s test database. But within a lock, the sound reverberates. The sonic waves are amplified as each reflected wave builds up the primary waves, which in turn become more reflected waves. In short, that 62 db-A an engine emanates (which is about the level of normal conversation) can quickly reach 90 db-A, about the level of truck traffic and the threshold at which hearing damage can begin. Besides, it’s annoying.

Many locks are also equipped with traffic lights. Red means stop and stay back a prudent distance; yellow means approach the lock, but do not enter; green means enter the lock.

I see most boaters getting hung up on the yellow light, taking it to mean they can proceed into the lock with caution. Actually, it signals boaters to position themselves to see inside the lock, making sure no boats from the opposite direction have yet to exit, and to anticipate the final approach to tying up against the lock sides. While we’re at it, always pull as far forward into the lock as you can, without going so far as to impede operation of the forward set of doors.


And…They’re Off!
I sometimes wish bridges had traffic signals down on the water. Transiting bridges, I’ve noticed a sort of slow-speed race develop.

The boats begin without leaving wakes. Then, apparently some deep psychological trigger fires the competitive instinct. A skipper realizes that the other boat is going to “beat” him. At this point, some otherwise civilized folks begin increasing throttle in an attempt to pass, as everyone tries to squeeze through the opening. Calls for reason are usually futile: “I’m doing 6 mph…just what the sign says.”

Well, let me tell you, there’s wake-free 5 knots and there’s 5 knots that creates a roiling wave as the transom is pulled down by increased propeller torque. Upset by such a wake, an idling boat can lose control or be carried aside into the bridge or another boat. So hang back, slow down and let the other guy go. Once one boat starts acting squirrelly in close quarters, a domino effect occurs. Better to be clear of that fray.


Courtesy, they say, is contagious. Most boaters exemplify that principle. But a few just don’t realize how much we depend upon each other to act responsibly on the water. So practice etiquette at every turn. It might catch on.


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