Twofold Bay (general dive/snorkel area)

High risk: Commercial vessel traffic

Twofold Bay hosts a deep-water port with commercial shipping. Snorkelers must stay well clear of shipping lanes and avoid areas near the Port of Eden wharves.

Moderate risk: Boat traffic

Commercial shipping, cruise ships, Navy vessels and recreational boats operate in the port area of the bay; stay clear of shipping channels.

Moderate risk: Unpatrolled beaches

Most beaches in Twofold Bay are unpatrolled — no lifeguards. Only Aslings Beach has summer patrols.

Moderate risk: Strong Tidal Currents

As a deep natural harbour with significant tidal exchange, currents can be strong around the heads, the entrance, and near the Navy Wharf. Check tide charts before entering.

Moderate risk: Shallow entrance currents

The entrance to the sea at certain creek and lagoon entrances around the bay can be very shallow and dangerous, with strong outflow currents.

Moderate risk: Boat traffic in Port of Eden

Twofold Bay is a working deep-water harbour with commercial shipping, navy vessels and cruise ships. Snorkellers must stay clear of shipping channels and wharf areas.

Moderate risk: Confined cave swim-throughs

Cave and swim-through entrances can be narrow and require good buoyancy control; low visibility may disorient in enclosed spaces.

Moderate risk: Swell surge in caves

Swell surge can push divers into cave walls; calm seas (less than 1m) essential for safe cave penetration.

Moderate risk: Swell and rip currents

Ocean swells can push into the bay entrance and exposed beaches like Aslings Beach, creating strong rip currents, especially during southerly winds.

Moderate risk: Depth on wreck sites

The Tasman Hauler wreck sits at 20–25m depth and the Henry Bolte at 20–25m, beyond recreational snorkelling limits; these are scuba-dive only sites for certified divers.

Low risk: Cold water temperatures

Water temperatures can be cool year-round due to southerly currents; a wetsuit (3-5mm) is recommended.

Low risk: Rocky Reef & Cave Hazards

Offshore reefs and caves popular with divers present entanglement and disorientation risks for inexperienced snorkelers. Strong surge can push swimmers into sharp reef edges.

Low risk: Strong currents at headlands

Tidal currents can run strongly around the headlands and at the entrance to the bay, particularly during outgoing tides.

Low risk: Bluebottle Jellyfish

Bluebottle jellyfish can be present in warmer months.

Low risk: Changing Tidal Currents

Tidal flows through the bay entrance and around headlands can create unexpected currents, especially near entrance channels.

Low risk: Poor Visibility After Storms

Runoff from the Nullica River and surrounding catchment can reduce visibility drastically after heavy rainfall, particularly in autumn and winter.

Low risk: Variable depth transitions

Some cave sites have sudden depth changes from shallow (5m) to deep beyond 20m, risking rapid descent without proper weighting.

Low risk: Shark presence

Bull sharks and other sharks are occasionally sighted in the bay and estuarine areas, particularly near river mouths during warmer months.

Low risk: Cool water temperatures (winter/spring)

Water temperatures drop significantly from June to October, with conditions requiring a 7mm wetsuit or drysuit for comfort and safety.

Low risk: Variable visibility

While summer and autumn often see 20m+ visibility, winter and spring can bring reduced viz due to swell and run-off.

Low risk: Boat traffic in harbour

Twofold Bay is a working harbour with commercial and recreational vessel traffic; snorkellers and divers must maintain surface awareness and use a dive float.

Low risk: Variable currents

Tidal flows through the bay entrance and around the wharves can create moderate currents, particularly on outgoing tides.