Overview
- The prefectures of Gironde, Landes and Pyrénées‑Atlantiques issued high‑risk alerts for baïnes covering Thursday 21 and Friday 22 May and say the danger will persist through Friday evening.
- A baïne is a sand‑cut cavity between the shore and a sandbar that creates a powerful rip current during specific tide hours and can shift location as the seabed moves.
- Lifeguards and SNSM crews are urging people to swim only between the supervised flags, remain calm if carried out to sea, call for help and use the international distress signal.
- Voies Navigables de France highlighted a sharp rise in inland drownings in 2025 and warned that unsupervised swimming in rivers, canals and near locks or dams is particularly dangerous.
- Officials warn that the incoming heatwave will boost beach and river visits, raise the chance of incidents and increase demand on rescue teams and local monitoring.