Operating instructions for the various types of lock...
Lock designs and instructions for passing locks
How locks work
See Locking, Sequence from VNF’s film "Navigating on the Canal des Deux Mers"
Different types of lock
The Canal des Deux Mers and its branches have about 200 locks, with many different design characteristics, dimensions, operating mechanisms and structures.
On the Canal de Garonne, the Montech-Montauban branch, the Junction Canal and the Canal de la Robine, the locks are "singles", in other words they are formed by a single chamber.
On the Canal du Midi, Pierre-Paul Riquet designed a series of locks with "multiple chambers", otherwise known as "staircase locks", to overcome the differences in elevation up to the summit level and down to the Mediterranean.
Thus a number of locks are "doubles" (2 chambers), "triples" (3 chambers), "quadruples" (4 chambers), "quintuples" (5 chambers)... and even one "sextuple" at Fonserannes where 6 (originally 7) chambers literally form a staircase of locks.
For operating rules, distinguish between:
1 - Mechanised locks
Locks are passed under the supervision of a lock-keeper. Once the boat has been tied up, the lock-keeper will close the gates and start the lock filling or emptying cycle. Follow his instructions and advice.
2 - Automatic locks
In automated locks, all manoeuvres are performed directly by the boater by turning suspended poles or using a remote control. Lock preparation and passage are controlled by fixed or flashing lights. There are no permanent lock-keepers on site. In case of a mechanical incident or accident, use the "emergency stop" control to stop the lock cycle and call a member of VNF’s operating staff who will come to provide assistance.
View and download brochure Liste des écluses mécanisées et automatisées sur le canal des deux mers (Format pdf - 53.6 kb - 05/11/2009)