A few meters upstream from this lock is the Déversoir de Villepinte, which allows excess water to flow out of the Canal Du Midi and into the nearby Fresquel Creek. This deversoir can also be used to drain this section of the canal in order to do maintenance work on the canal itself, often done during winter.
The big satellite dishes seen to the north of this lock are used to communicate with French submarines. They are a military installation. Link.
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