May 2012

Locking through

Pointers to ensure a safe passage

Locking through

The U.S. Army Corps of Engineers offers a few pointers to boaters locking through a dam.

  • Stay between the red and green buoys, which mark the river’s navigable channel.
  • Sit-down personal watercraft operators must wear Coast Guard-approved life jackets and remain seated. Stand-up personal watercraft must tie to an approved vessel, and operators must remain on board the approved vessel.
  • Wait for the green light and the whistle signal from the lock operator before entering the lock.
  • Boats going downstream should stay clear of traffic, 400 feet upstream from the end of the guide wall, while awaiting lockage.
  • When approaching a lock, boats should issue one long whistle blast followed by one short blast no more than one mile from the lock. Pull cords, which sound an alarm to let the lock operator know you desire lockage, are provided at the upstream and downstream ends of the lock wall.
  • Traffic signals guide you at many river locks: A steady red light means the lock master hasn’t seen you; a flashing red light means do not enter; a flashing amber light means approach the lock under full control; a flashing green light means enter the lock.
  • The lock operator may signal you with an air horn: One long blast, enter landward lock; two long blasts, enter riverward lock; one short blast, leave landward lock; and two short blasts, leave riverward lock.
  • Carry aboard at least 75 feet of mooring line to safely tie your boat to the lock wall.
  • When directed, approach the lock slowly with no wake.
  • Turn off your engine during the lockage so exhaust fumes can’t accumulate, and lower the volume on your radios and stereos.
  • Use fenders to prevent damage to your boat and lock walls.
  • When leaving the lock, wait for the lockmaster to sound the all-clear signal before starting your boat. Never start your engine until you are sure your bilge is free of fumes. Hold onto your lock lines until the boat in front of you has begun to move. Leave at idle speed, following the lockmaster’s instructions. Watch for boats waiting to enter the lock.

To learn more, take the Boating on Rivers, Locks and Lakes seminar at a squadron near you.



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Mastering Marlinespike

Hawser bend

Useful for joining two ropes of unequal sizes, the Hawser bend is helpful when joining a light line to a heavy one.


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