Agde Round Lock

The round lock at Agde is a lock on the canal at Agde.

It was built in 1676 and is the only Kesselschleuse with more than two terminals is operating in France. The third connection leads to a branch canal, which thus leads to the lower reaches of the river Hérault and a short way to the Mediterranean.

In the course of the Canal du Midi from the peak height Naurouze in the Thau an intermediate increase is overcome with this lock. This results from the jammed with a weir Hérault. This compared to the incoming channel higher levels of the Hérault is crossed. The increase is in accordance with lock table, up to 44 cm. In the lock Prades on the other side of the river, the corresponding descent takes place.

On connection to and from Beziers (lower panel ) is the Canal du Midi either lower or upper water. It can be locked against a higher ( drive to the Thau lagoon ) or a lower water level ( drive to the Mediterranean) in the lock chamber. For the second case, the lock at this point a second (outer, left) two-wing revolving gate which is closed during downward locks and holds back the water in the Canal du Midi. The first ( inner right) Gate stops - as if closed in the picture - the upward locks in the Hérault jammed the water from flowing out of the lock chamber. The reason for the second goal is that the traditional two-leaf swing gates can only lock in one of two directions. Together, they form an arrow pointing opposite to the direction of flow to be prevented.