Safety · Destination Guide
Marlborough Sounds Picton And Lermontov Wreck New Zealand
Temperate reef life, sheltered inlets, and New Zealand's most famous wreck dive
Updated Feb 13, 2026 • 21 sources
Safety And Conservation
The Marlborough Sounds can feel sheltered, but they are still open water with fast weather changes, cold temperatures, and busy marine traffic. Use local operators for site selection, treat wreck penetration and currents with respect, and build conservative surface support into every plan. Conservation rules are a core part of the experience, especially in marine reserves and around sensitive seabird colonies.
Top Risks
- Primary risk: Cold-water exposure and afterdrop
- Secondary risk: Tide-driven currents and unmarked reefs
- Emergency contact: Emergency Services (111)
- Safety overview: The Marlborough Sounds can feel sheltered, but they are still open water with fast weather changes, cold temperatures, and busy marine traffic.
Dive safety
- Treat cold exposure as part of your dive plan. Most divers use a 7mm wetsuit or a drysuit, plus hood and gloves.
- Carry and know how to deploy an SMB. The Sounds are a working waterway with fast boats and limited sightlines around headlands.
- For Long Island-Kokomohua and other outer-Sounds zones, expect tide-driven currents and the possibility of unmarked reefs and choppy water in strong wind.
- Wreck penetration on the Lermontov should only be attempted by trained teams with redundant gas, reels, lights, and clear separation and exit protocols.
- If a site feels "off", call it early. Cold water punishes decision fatigue.
For any life-threatening emergency, call 111 (New Zealand emergency services). For diving-specific incidents, contact the Diver Emergency Service (DES) on 0800 4DES 111 (0800 4337 111) for expert coordination and recompression guidance.
Hyperbaric support is not located in the Sounds itself. Christchurch has a 24-hour acute hyperbaric service for New Zealand south of Taupo, and DES can coordinate referral and evacuation pathways based on your location and condition.
Carry DAN-style dive accident cover or equivalent insurance that includes evacuation, and keep a written emergency plan on the boat.
Snorkel and freedive safety
Cold-water exposure and afterdrop
Water temperatures around 13°C to 18°C can still sap energy, especially on repeat days. Dress for the second dive of the day, keep windproof layers for the boat ride, and treat warmth as a safety system.
Tide-driven currents and unmarked reefs
DOC warns of unmarked reefs, tidal changes, and strong currents around charted rocks in parts of the Sounds. Use local operator briefings, plan entries and exits carefully, and do not push sites in strong wind.
Boat and ferry traffic in narrow channels
The Sounds are a working waterway. Always assume boats are moving fast around headlands. Divers should carry an SMB and deploy it early, and freedivers and snorkelers should tow a float and stay tight to the plan.
Wreck penetration risk on the Lermontov
Penetration adds overhead, entanglement, silt-out, and exit-route complexity. If you are not trained for wreck overhead environments, keep it exterior and enjoy the scale, marine life, and structure from the outside.
Wildlife and protected areas
- Marine reserves are no-take: no fishing, no collecting, and no feeding fish. DOC explicitly asks visitors not to feed fish in the Long Island-Kokomohua Marine Reserve.
- Anchor with care. Avoid anchoring on sensitive seabed and consider drift plans or mooring options where permitted.
- Follow DOC marine mammal guidance and keep respectful distance from dolphins, seals, and whales.
- King shags breed only in the Marlborough Sounds and are easily disturbed. DOC and local rules advise keeping boats at least 100 m from colonies.
- Help prevent marine pest spread. Clean and dry gear between regions and report suspected pests to MPI (0800 80 99 66).
Do Not Do This
Avoid entering when cold-water exposure and afterdrop. Confirm local briefings before committing.
Emergency contacts
| Contact | Role | Phone | Availability |
|---|---|---|---|
| Emergency Services | Police, Fire, Ambulance | 111 | 24/7 |
| Diver Emergency Service (DES) | Diving medicine hotline and recompression coordination | 0800 4DES 111 (0800 4337 111) | 24/7 |
| Coastguard New Zealand | Marine emergency and assistance | VHF Ch 16 / *500 (non-urgent) / 111 (emergency) | 24/7 (emergency) |
| Rescue Coordination Centre New Zealand (RCCNZ) | National search and rescue coordination | 0508 4 RCCNZ (0508 472 269) | 24/7 |
| DOC Hotline | Department of Conservation incident line | 0800 DOC HOT (0800 362 468) | 24/7 |
| Report poaching | Illegal fishing and take reporting | 0800 4 POACHER (0800 476 224) | 24/7 |
| MPI Pest and Disease Hotline | Report marine pests and biosecurity threats | 0800 80 99 66 | 24/7 |