Lock and Dam 21 is located in Quincy, Illinois, and is 324.9 miles above the confluence of the Mississippi and Ohio Rivers.
Locking Through: Safety is the prime consideration when locking any type of recreational vessel through a lock. Operators must require all passengers to wear a coast guard approved life jacket. Always wait and then approach the lock away from the posted restricted areas upstream and downstream of the dam. The marking of restricted areas may consist of signs, buoys, aids to navigation, and lights. Do not wait in the path of a towboat leaving the lock. 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. The lock operator will advise vessels whether conditions permit it to approach the lock and moor alongside walls or whether it is to stay clear of the approach. Locking priority will be established as set forth in Navigation Notice 1, which is issued annually. If a delay is apparent, the vessel will be informed of the approximate length of the delay. 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 14. 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. Lock personnel will also be better able to communicate changes of locking order on Channel 14.
- 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. Cell phone usage for lockages is cumbersome to the lock and does not expedite locking. Lock personnel do not carry phones, only radios. Calls are welcomed for safety concerns and general information.
- Pull Ropes: Pull ropes/chains with talkback speaker to sound an alarm letting the lock operator know that you desire lockage, are provided near the end of the upstream and downstream lock guide wall and are found in a ladder recess.
- Once you have made contact with lock personnel you will be instructed by traffic lights, and/or marine radio.
- Light Signals: Red, Yellow, 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. A yellow light means that the lock crew is getting the chamber ready for you. 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 while locking unless you are the only boat in the lock chamber. Bring an adequate amount of line because not all locks provide lines. Do not tie off. Simply take in or pay out line as the water level changes. Use your bumpers.
- Air Horn Signals: Permission to leave the lock shall be indicated by the lock operator by one short blast.
Obey all the instructions of the lock personnel. Your total time in the lock will be approximately 15 minutes. The pool in the lock chamber will be raised or lowered 8.0 to 38 feet depending on which lock you are at in the Rock Island District. When the pool reaches the proper level, the gates will be opened for your departure. Please wait for the operator's signal to release your line and exit the lock at a slow NO WAKE speed.
Locking Times: Mississippi River Locks in the Rock Island District normally operate from early March thru early December. Locks are open 24/7 seven days a week. Locks 14 and 15 also utilize an auxiliary lock that is normally operated from approximately May through September.
Navigating the Channel: Stay between red and green buoys. They mark the river’s navigational channel. The Rock Island District Mississippi River waterway is 313.9 miles long and has 12 locks along the waterway. Its navigation channel varies in width, and it has a minimum depth of 9 feet. Locks 11-18 and 20-22 are 110 feet wide by 600 feet long. Lock 19 is 110 feet wide by 1,200 feet long. Lock 14 and Lock 15 have an auxiliary lock that is 80 feet wide by 320 feet long and 110 feet wide by 360 feet long, respectively.
Upper Mississippi River Locks Contact Information
- Lock and Dam #11 (563) 582-1204
- Lock and Dam #12 (563) 872-3314
- Lock and Dam #13 (815) 589-3313
- Lock and Dam #14 (309) 794-4357
- Locks and Dam #15 (309) 794-5266
- Lock and Dam #16 (309) 537-3191
- Lock and Dam #17 (309) 587-8125
- Lock and Dam #18 (309) 873-2246
- Lock #19 (319) 524-2631
- Lock and Dam #20 (573) 288-3320
- Lock and Dam #21 (217) 222-0918
- Lock and Dam #22 (573) 221-0294