Safety · Destination Guide
Cold-water wrecks, kelp reefs and Atlantic wildlife across Cornwall's two coasts
Cornwall's main risks are environmental and logistical: cold, Atlantic swell, strong tidal streams, variable visibility, rocky exits, kelp and lines, boat traffic, and weather-driven plan changes. The Manacles and exposed Newquay headlands require local tide knowledge, while harbour areas require strict surface discipline. In a sea emergency, contact HM Coastguard by VHF Channel 16 or dial 999 or 112, provide 100% oxygen when trained and available, and then contact the National Diving Accident Helpline. Conservation means more than not littering: maintain buoyancy over fragile sea fans and anemones, give seals and sharks space, avoid anchoring on sensitive habitat, and leave wreck material in place.
Give 100% oxygen through a tight-fitting mask when trained, keep the casualty comfortable and lying down unless breathing or vomiting requires another position, hydrate an alert casualty, call emergency services, and seek specialist advice. Do not recompress in the water and do not let apparent improvement cancel the referral.
Royal Cornwall Hospital in Truro has a 24-hour Emergency Department for serious and potentially life-threatening conditions. Diving casualties should still enter the coordinated emergency pathway rather than self-driving directly to a chamber. DDRC Healthcare in Plymouth provides specialist hyperbaric support and publishes the National Diving Accident Helpline for England and Wales. At sea, call the Coastguard first by VHF Channel 16 or 999; on land, call 999 for a seriously unwell or rapidly deteriorating patient. Keep dive profiles, gas details, symptoms, first-aid times, medications, allergies, and insurance information ready for rescuers. NHS 111 is for urgent advice when the situation is not immediately life-threatening, not a substitute for emergency activation in suspected serious diving illness.
Strong tidal streams
The Manacles and exposed headlands can run hard outside the planned window. Use a local skipper, confirm slack-water assumptions, carry a DSMB, and do not extend a dive because the wreck is attractive.
Atlantic swell and rip flow
Newquay shore sites may look inviting while still carrying surf, rip currents, surge, and difficult exits. Enter only on locally supported flat-water plans and maintain a south-coast fallback.
Cold exposure
Water can approach 7°C in late winter, and wind chill continues after surfacing. Match suit, hood, gloves, gas plan, hydration, and surface interval to the coldest part of the day.
Boat and harbour traffic
Falmouth is a major working harbour and Newquay or Porthoustock can have fishing, leisure, and working craft. Follow exclusion zones, use surface marking, and avoid surfacing in channels.
The Manacles Marine Conservation Zone sits within a wider Fal and Helford protected seascape that includes SAC, SPA, MCZ, and SSSI designations. Seasearch surveys record dense jewel anemones, pink sea fans, sponges, soft corals, hydroids, kelp, fish, and returning crawfish. These organisms can be damaged by poor buoyancy, fin strikes, grabbing, or careless shot and anchor placement.
Recovered wreck material must be reported to the Receiver of Wreck within 28 days. Protected places are look-but-do-not-touch; controlled sites require authorization. The best default on every wreck is to photograph, record, and leave all material where it lies.
Do Not Do This
Avoid entering when strong tidal streams. Confirm local briefings before committing.
| Contact | Role | Phone | Availability |
|---|---|---|---|
| UK Emergency Services and HM Coastguard | Immediate life-threatening or at-sea emergency; ask for Coastguard when relevant | 999 or 112; VHF Channel 16 at sea | 24 hours |
| National Diving Accident Helpline | Specialist diving accident advice and chamber coordination for England and Wales after emergency services are activated | 07831 151 523 | 24 hours |
| DDRC Healthcare | Hyperbaric and diving medicine center in Plymouth | +44 1752 209999 | 24-hour emergency service; use the helpline pathway for a diving incident |
| Royal Cornwall Hospital Emergency Department | Nearest major 24-hour Emergency Department in Truro | 01872 253111 or 01872 253113 | 24 hours |
| NHS 111 | Urgent medical advice when the situation is not immediately life-threatening | 111 | 24 hours |