Noirmoutier-en-l'Île tide times

The Passage du Gois is passable for approximately two hours on either side of low water — roughly four hours per tidal cycle. The exact times shift each day because low water is approximately 50 minutes later every 24 hours, and the range varies across the spring/neap cycle. For the authoritative crossing schedule, go directly to the official SHOM publication or the Vendée département's Gois information service. Never cross outside the published window: the tide returns quickly and the causeway floods faster than most people expect.

The causeway floods completely on a spring high tide — the water depth over the road can exceed 1.5 m at the lowest point of the Gois. Refuges (échappées) are positioned at intervals along the causeway: tall platforms accessible by ladder where stranded pedestrians can wait above the water. Vehicles cannot be saved once the flood reaches wheel height. Emergency services respond, but recovery is not guaranteed before the vehicle is submerged. The practical answer: use the official SHOM crossing schedule and leave a safety margin.

Fleur de Sel de Noirmoutier is a hand-harvested sea salt — the thin crystalline crust that forms on the surface of salt pans in dry, sunny, lightly windy conditions. Paludiers (salt workers) skim it from the evaporation basins using a wooden rake called a lousse. The harvest season runs June to September, depending on weather. Noirmoutier's salt pans (marais salants) occupy the island's eastern marshes; the flooded basins fill from the sea via sluice gates, and the tidal cycle regulates the water exchange.

Mean tidal range at Noirmoutier is approximately 4.0–4.5 m, slightly lower than the 4.5 m at Saint-Nazaire because the island sits on the outer Vendée coast rather than inside an estuarine funnel. Spring tides push the range to around 5.0 m. Neap tides drop to approximately 2.0–2.5 m — on small neaps, the Gois crossing window expands and the tidal exposure of beaches is less extreme. The tidal type is semidiurnal: two high waters and two low waters per day.

Tide predictions on this page come from Open-Meteo Marine models (±45 min, ±0.2–0.3 m). For the Passage du Gois crossing schedule specifically, use the official SHOM Gois publication — it is the only authoritative source. For boating around the island, the Fromentine channel, and Baie de Bourgneuf, use current-edition Navicarte charts and SHOM tide tables referenced to the Noirmoutier or Saint-Nazaire gauge. Do not navigate these shallow, current-prone waters on app predictions alone.