Koumac

Before boarding, verify the skipper's weather/tide decision, site briefing, qualifications, buddy procedures, onboard oxygen, reliable communications, evacuation route and insurance. Deverd's reported caves and cavities are an overhead hazard: do not penetrate without separately verified permissions, appropriate specialized training, equipment, supervision and a specific safe plan. The shallow Jardin d'Eden introductory experience is a different product. Reef-pass currents, surface chop, boat channels, coral cuts and changing sea state are relevant. Freediving requires its own trained safety buddy and rescue protocols; snorkeling must not be sold as certified apnea instruction. Avoid swimming near Pandop marina, murky river outlets, after rain, at dawn or dusk, or where closures apply. Consult Australia's New Caledonia swimming advice.

As of an Australian advisory updated August 27, 2026, Koumac hospital was listed for external consultations only; the emergency-service hospital in northern Grande Terre was listed at Kone, and the recompression chamber at Noumea. Older government and local directory pages still mention Koumac emergency services, so the operational situation is conflicting and must not be assumed. For serious illness or suspected decompression injury, call 15 immediately; for maritime response call 16 / VHF 16, identify the boat and position, provide oxygen if trained, and follow medical direction. Medical transfer to specialized treatment may be lengthy and weather-dependent. No confirmed Deverd evacuation time or local chamber was established. Insurance must explicitly cover scuba and any proposed specialty activity, air evacuation and recompression.

Respect Province Nord protected-lagoon and island closures, fisheries rules and community permissions. Its July 3, 2026 access table marked Yan'Dagouet closed to landing in Koumac; statuses change, and a flag or protection net can close part of an otherwise open islet. Threatened fairy terns nest on ground-level sand/coral islets May-September, while other seabirds often nest October-March. Never land near colonies, bring dogs, disturb eggs, touch or stand on coral, feed wildlife, collect shells/coral, or anchor on reef. Check Province Nord's live islet guidance and customary land permissions. UNESCO listing of some New Caledonian lagoon clusters is conservation context, not evidence of unlimited access or a uniform admission fee.