The Sivens forest, near Gaillac, is the site of protest by opponents of the construction of a dam on the Tescou, a tributary of the Tarn. In 2015, clashes led to the death of an opponent, Rémi Fraisse, and the abandonment of the project. But the subject of water retention remains relevant, as explained this article from Tarn Libre. It is undoubtedly within this framework that a Temporary Regulated Zone (ZRT) was created above the Sivens forest. It is intended to protect “ aircraft flights without crew on board ". When the ZRT is active, it is prohibited for drone flights.
ZRT Sivens can be activated every day except weekends and public holidays from October 5 to October 29, 2023 from 10:00 a.m. to sunset (08:00 UTC to sunset) and from October 30 to December 22, 2023 from 09:00 a.m. to sunset sun (08:00 UTC at sunset). Then every day except weekends and public holidays from January 2 to February 28, 2024 from 09:00 to sunset (08:00 UTC to sunset)
source: The SIA