Locks, signalling and operating systems

Traffic lights

Most locks have traffic lights and you will see these on a triangular board close to the lock gates. Green and red are obviously Go and Stop respectively; if you see green with amber this means the lock is readying itself for you.

Do not enter or exit a lock until you see a green light on its own, unless you are following another boat when the light may change as they enter the lock. A photoelectric sensor on the lock wall has detected the passage of a boat and, assuming it is a large one gives following traffic a red light. If the other boat knows you are following they will delay operating the automatic mechanism until you are safely inside.

Be aware that there may be traffic approaching from the other direction or already in the lock and you will need to wait. Stay well back from the lock gates at the side of the canal whilst waiting as it may be a peniche coming out and it will need lots of room until its stern has cleared the lock.

If the lights are not working it means that the lock is out of order or is being controlled by a lock-keeper. There may be two red lights. Moor up and approach the lock on foot. If there is no sign of a lock keeper make sure that you are there during lock opening hours, if so use the intercom or phone to inform the authorities of the problem. Don’t forget to give them the number of the lock and/or the name. In most areas these days the passage of boats is tracked by the authorities and if you do get stuck in a lock, even if you do not call, you will find that someone will come eventually, so - don't panic.

Types of operating mechanisms


The lock keeper in his/her cottage at the lock-side is becoming a rare breed, although there is a lock keeper on site on all the major waterways such as the Rhône and Saône.

On the smaller canals and rivers if the locks are still being staffed you are more likely to find a mobile lock keeper who will travel with you in their little car, or on a moped through a section of the canals. You are expected to help the lock keeper in the smaller locks by operating one side of the lock when your boat is level with the lock quay. This is also a wonderful opportunity to chat to your lock-keeper and add to the enjoyment of your holiday. It is not necessary to tip them but they often appreciate a beer or can of soft drink from your fridge on a hot day. Details of operation of automatic locks will be found on the next page.

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