This site boasts several engineering structures of great architectural quality. They were built to counter the danger of rising water levels on the Aude river, which had always been an issue. This section of the Canal de Jonction was created in the same area as the flood plains for the river.
This is a lock with a single lock chamber (basin) covering a difference in height of around 3 metres. This lock has an important role to play in ensuring the protection of the Canal de Jonction.
Upstream from the lock, the canal is protected from the high water levels of the Aude thanks to a system of embankments that surround the canal up to Sallèles-d’Aude.
Downstream from the lock there is an area that was designed to be flooded during flash floods: the spillway.
This bridge was designed to provide quick access to all areas of the site, and boasts an elegant architectural style, with a segmental arch and four semi-circular sets of steps at each corner. During flash floods, action must be taken quickly to put the defence mechanisms in place. This bridge is at the downstream end of the lock and so it has a damming role to play when water levels are at their highest.
This monumental building is 30 metres long and it cannot be missed on the left banks of the canal between Gailhousty lock and the Aude river.
The front façade on the canal side features vertical crenellations that plunge down into the water.
At the rear, there are 5 arch openings and the 8-km-long Canal du Gailhousty, also known as 'La Saignée', flows to Capestang lake.
Inside this building there are no less than 15 huge valves. The purpose is not to evacuate excess waters from the Canal de Jonction, but to allow excess waters from the Aude river to pass through. The initial idea was to divert this water that is rich in fertile silt, into Capestang lake so that it would be silted and perfect for crops.
On the façade facing the canal, there is a sculpture of the coat-of-arms of Monseigneur Dillon, the last archbishop of Narbonne, who was behind the construction of the Canal de Jonction. There is also an Occitan cross as a reminder that the Province of Languedoc funded the construction work.
The building also includes lodgings that were originally intended for the lock keeper, also in charge of operating the spillway valves.
On the opposite side of the spillway building, there is a dry dock for boat repair and careening.
How does it work? There is a gate on the downstream corner of the spillway building, and when this gate is closed, the space between the lock and this gate is filled with water arriving from the Canal de Jonction. When it is filled to the maximum level, the careening platform is underwater and boats can be positioned there. The sluices are then opened to empty the chamber. The boat is gently positioned onto the special props. In just a matter of minutes, the boat is then out of the water, and repair work can commence.
This dry dock was created in the 1980s to replace the one in Sallèles-d’Aude, that was destroyed when modernisation work was carried out to extend the locks.