Safety · Destination Guide
Tide windows, chalk reefs and a century-spanning wreck archive on England's south coast
Sussex combines genuine cold-water and tidal risk with legally protected natural and cultural heritage. Use a qualified local operator, preserve a weather reserve day and treat every offshore target as conditional. The safest plan aligns certification, recent experience, gas, exposure protection and decompression capability with the actual site selected after the skipper reviews wind, sea and slack.
Use a torch even by day, maintain close buddy contact and avoid penetrating unstable wreckage unless specifically trained and equipped. Carry at least one accessible cutting tool. Deploy the DSMB early enough for surface cover to track the ascent, but follow the skipper's procedure around a shotline. On drift dives, remain with the agreed group marker. Abort for cold, excessive current, lost visibility, equipment problems or a missed slack.
Signal clearly, protect against wind chill and report any omitted decompression, rapid ascent, neurological symptom, unusual breathlessness or chest pain immediately. For a suspected diving injury, call 999 or the British Hyperbaric Association helpline and follow specialist direction rather than self-driving to a chamber.
Royal Sussex County Hospital serves the Brighton cluster, Eastbourne District General Hospital has a 24-hour emergency department, and St Richard's Hospital in Chichester is the principal local emergency option for Selsey. These hospitals are not a substitute for diving-medicine coordination. The British Hyperbaric Association Diving Accident Helpline, 07831 151523, is available 24 hours and can direct assessment and chamber referral. In a life-threatening or coastal emergency, call 999 or 112 and ask for the Coastguard when maritime rescue is involved. Keep oxygen, first-aid capability, diver details and a written dive profile available for responders.
Short slack and strong tidal flow
Many wrecks, drifts and Selsey sites are practical only around a locally calculated slack. Missing the window can turn a manageable plan into a high-work current dive.
Variable or rapidly lost visibility
Fine sediment, plankton, wind and runoff can reduce visibility to a few metres. Maintain close buddy contact, carry a torch and avoid finning or kneeling into soft seabed.
Cold exposure
Late-winter water can be near 5°C to 9°C, and summer boat wind still strips heat. Plan insulation for repetitive dives and long surface intervals, not only the first descent.
Fishing gear and boat traffic
Wrecks attract fishing activity, and marina, harbor and inshore zones can have frequent vessel movement. Carry an accessible cutting tool and use the surface-marking system specified by the skipper or guide.
Sussex Marine Conservation Zones protect chalk, rock, sand, mud, mixed sediment, peat and clay habitats as well as features associated with native oysters, seahorses and reef communities. Divers should use precise buoyancy, avoid contact with chalk and fragile growth, secure gauges and lights, and never collect wildlife. Do not disturb cuttlefish courtship or egg-laying.
Underwater heritage requires equal care. Do not remove artifacts, tie into fragile structures, force entry or move ammunition. Protected wreck zones can require a licence, and intrusive work at a scheduled monument can require Scheduled Monument Consent. Any recovered wreck material must be reported within 28 days. At Pagham Harbour and Medmerry, obey reserve restrictions, stay away from bird islands and breeding groups, and do not launch prohibited water sports.
Do Not Do This
Avoid entering when short slack and strong tidal flow. Confirm local briefings before committing.
| Contact | Role | Phone | Availability |
|---|---|---|---|
| UK emergency services and HM Coastguard | Life-threatening, maritime and coastal emergencies | 999 or 112; ask for the Coastguard for an incident at sea or on the coast | 24 hours |
| British Hyperbaric Association Diving Accident Helpline | Specialist advice and chamber coordination for suspected diving illness | 07831 151523 | 24 hours |
| NHS 111 | Urgent medical advice when the situation is not immediately life-threatening | 111 | 24 hours |