Lock and Dam 24

Lock and Dam 24Locking Through: Safety is the prime consideration when locking any type of vessel through a lock. Operators must require all passengers to wear a Coast Guard approved life jacket. As you approach a lock on the Upper Mississippi River, you must inform the lock operators of your desire to pass and they, in turn, will indicate to you when it is safe to proceed into the lock. There are several methods of communication with the lock personnel, as follows.

  • Radio:  Is the preferred method of making contact with the lock on the Upper Mississippi River. If your vessel is equipped with a two-way radio, please establish contact with the lock on VHF (FM) Channel 12. The lock will then move you to their working channel. Do this well in advance of your arrival at the lock so that the passage of all vessels may be facilitated, and allow the operator time to prepare the lock.

  • Cell Phone: Cell phones may be used to contact the lock when within sight of the lock. Please keep in mind lock operators are very busy and are not always able to answer the phone.

  • Pull Ropes: Pull ropes which sound an alarm letting the lock operator know that you desire lockage, are provided at the upstream and downstream ends of the lock guide wall.                                                                                                       

  • Once you have made contact with lock personnel you will be instructed by traffic lights, air horn signals, and/or marine radio.

  • Light Signals: Red and green signal lights are located at both ends of the lock. A red signal indicates that the lock is closed in your direction and you should wait for the lock operator to give you the green light before you proceed into the lock. The green signal means that you have been cleared to enter the lock chamber, unless you have been informed by the lock operator that you are required to yield to a commercial vessel. Proceed only when the signal light is green and enter the lock at a slow NO WAKE speed. The lock personnel will direct you toward one of the lock walls. You are required to catch and tend a line on one of the floating mooring bits. Furthermore, many Mississippi River locks utilize a strobe light at the lock to signal recreation type vessels that the lock is ready for entry. Such lights are used exclusively to signal recreation craft.

  • Air Horn/Whistle Signals: Vessels desiring passage through a lock shall notify the lock operator by one long blast followed by one short blast of a horn, whistle, or megaphone, when within one mile from the lock. When the lock is ready for entrance, the lock operator shall reply with  one long blast of a horn, whistle or calls through a megaphone to enter the landward chamber or two long blasts of a horn, whistle, or calls through a megaphone to enter the riverward chamber in the case of twin locks. When the lock is not ready for entrance, the lock operator shall reply by four or more short distinct blasts of a horn, whistle, or call through a megaphone (danger signal). Permission to leave the lock shall be indicated by the lock operator by one short blast in the case of a single lock or to leave the landward chamber in the case of twin locks. Two short blasts indicates permission to leave the riverward chamber in the case of twin locks.

    Obey all the instructions of the lock personnel. Your total time in the lock will be approximately 30 minutes. The pool in the lock chamber will be raised or lowered about 15 feet depending on which lock you are in on the Upper Mississippi River. When the pool reaches the proper level, the gates will be opened for your departure. Please wait for the lock operator's signal to release your line and exit the lock at a slow NO WAKE speed.

    Lockages for pleasure craft will be conducted upon request, however, any transiting craft take priority. If no other traffic is present at the lock, the pleasure craft may be locked as soon as feasible in the auxiliary lock. If a delay is apparent, the pleasure craft will be informed of the approximate length of the delay. The lock operator will advise the pleasure craft whether conditions permit it to approach the lock and moor alongside walls or whether it is to stay clear of the approach. Pleasure crafts may be locked through with transiting crafts at the lock operator’s discretion.

    Navigating the Channel: Stay between red and green buoys. They mark the river’s navigational channel. The Upper Mississippi River is approximately 670 miles long and has 29 locks along the river. Its navigation channel is at least 300 feet wide at all points, and a minimum depth of 9 feet. Lock & Dam 24 and Lock & Dam 25 have a single lock chamber that is 110 feet wide by 600 feet long. Melvin Price Locks & Dam and Locks 27 each have two lock chambers that are 110 feet wide by 600 feet long and 110 feet wide by 1,200 feet long.


    Upper Mississippi River Contact Information:

    Lock & Dam 22 – 573-221-0294

    There is NO Lock & Dam 23.

    Lock & Dam 24 – (573) 242-3524

    Lock & Dam 25 – (636) 566-8120

    Melvin Price Locks & Dam – (618) 462-1713

    Locks 27 – (618) 452-7107