Ewens Ponds are three interconnected sinkholes just outside of Mount Gambier in South Australia that are yours for the snorkelling! Dive in and discover the strange and beautiful underwater world.


  • Snorkelling through three connected freshwater limestone sinkholes
  • Swim through an underwater garden
  • Underwater visibility up to 80 metres

Where in The World is Ewens Ponds?

Every time I head back to my hometown, there are three things I always try to do – spend time with my parents, pay my grandparents a visit, and dive in for a snorkel at Ewens Ponds, the underwater oasis on Boandik land and one of many sinkholes around Mount Gambier.

Ewens Ponds are three connected, limestone-fed sinkholes in the middle of Eight Mile Creek about 20 minutes out of Mount Gambier. Each of the ponds is surrounded by native reeds and linked with garden-laced channels, making it a bloody spectacular freshwater snorkelling route.

These aren’t the only sinkholes around Mount Gambier! Check out Piccaninnie Ponds for more sinkhole snorkelling.


Breathtaking From The Beginning

As you jump off the pontoon and into the first pond, it takes your breath away. Mostly because it’s ridiculously cold (15 degrees all year round) and you’re trying to catch your breath through a snorkel, but also because the water clarity is unlike anything you would’ve ever experienced before. 

This is your first true sighting of the rich blue water and underwater greenery that surrounds the pond, all of which is easily visible with water visibility up to 80 metres. You can see right through to the other side of the pond!

Through The Channels

Swimming through to the opposite side of the pond, you’ll find the entrance to the first channel. Where the pond turns into a shallow creek is where you kick your way through, trying not to let your fins damage the plant life engulfing you. The clarity of the water allows the plants to receive sunlight and grow from the water bed towards the surface, with some plants in the ponds reaching six metres tall. 


Ewens Ponds is a Sink-Hole Snorkelling Haven, Jack Brookes, swimming, snorkel, underwater, sea grass


Vibrant green turns to deep, dark blue as the channel opens up into the second pond. When I pop my head up, there’s nothing around but reeds, a metre or two above the surface, and no sign of human life – how good! I dive back down towards the silt bed that covers the limestone bottom where a few fish and the occasional crayfish hang out.



After exploring the second pond, venture to the opposite side from which you entered and follow the next channel through to the third pond. Feel your brain try to process the popping colours only mother nature can plate-up as you swim through the creek and into the final pond. 

Once you’ve finished exploring the third pond and the cave inside, find the pontoon to clamber back out of the water. This’ll put you at the start of a dirt path that takes you on a short walk back through the reeds to the car park, as the hum of another microadventure and hour well-spent kicks in.


Ewens Ponds is a Sink-Hole Snorkelling Haven, Jack Brookes, swimming, snorkel, underwater, moss

Essential Gear

  • Wetsuit 
  • Snorkel and mask 
  • Fins
  • Permit

Permits and Equipment Hire

While you can drive into the park and check it out for free, you need a $15.50 permit to snorkel and dive. You have to book in an hour time slot online before you arrive. You’re allowed up to two time slots a day and can book them back-to-back if you want more time in the ponds.

If you don’t have any snorkelling equipment, you call through the Allendale General Store to hire some. It’s less than 10 minutes up the road.

How To Get There

Ewens Ponds Conservation Park is only 30 minutes from Mt Gambier or 10 minutes from Port MacDonnell. You can follow the signs from Bay Rd, or Lower Nelson Road and a white metal road will take you into the park.

Skill Level


If you’re swimming through to the third pond, be aware that there isn’t anything to grab on to, and you’ll be treading water until the final pond. Those less confident can stick to the first pond, and grab onto the pontoon for a breather.

Read more: How To Stay Safe Around Water // Swimming Hole Safety

Time Taken / Distance Covered

1 hour / App. 250m swim