Guided Riwaka Cave Diving
The Riwaka Caverns are a very interesting yet relatively easy freshwater cave dive (Advanced Open Water Divers) with the company of highly experienced guides.
Thirty minutes north of Nelson at the base of the Takaka Hill the Riwaka River surfaces from an underground journey below the Takaka Hills into a subterranean cave system known as the Riwaka Resurgence.
The Resurgence itself is a place where the water emerges from the hill via the cave to form a deep, clear pool. This ravine-like cul de sac, with the foot of the Takaka Hill towering above is strewn with huge marble boulders giving you an indication of the geography of the region. The setting is inspiring with pungas mostly 5 to 7 metres high, and there are a number of tall, ancient totara and other forest giants all around.
When standing at the cave entrance only a small pool and narrow opening can be seen, but the opening into the cave is much larger beneath the surface where a torch is needed almost immediately. The lead diver carries the penetration line and swims 15 metres (49.2 feet) through a straight sump which is 12 metres (39 Feet) deep. The landscape is unique: lifeless, still, silent and cold. At the end of the sump, a short climb with your fins off, you cross shallow rapids puts you in sump two. This sump is the same depth, but twice as long. It is difficult to describe the feeling of being inside a big, empty chamber and somehow magically disappearing underneath it. The highlight of the dive is the massive chamber at the end of sump two. Here scuba equipment is removed and stalactite and stalagmite formations can be admired and The sheer size of this chamber is totally unexpected; a magnificent waterfall of pink limestone cascades 20 metres or so down one side. It is inviting but don’t climb it. By clambering over bus sized boulders you can walk through another small sump where the passage is narrower and the water flows with a hiss and a roar.
Cave diving can be hazardous. To do this dive you need to be with an experienced diver who knows the cave system. Specific rules should be adhered to and respected:
- Never leave your rope – it is your lifeline. Visibility may change quickly due to rain or siltation.
- Conserve Air - use one third in, one third out and a third spare. Inside the cave is dark and cold. This will increase air consumption.
- Two Torches – Take at least two torches with new batteries.
- Batteries – Other than those specified may cause the bulb to flicker and blow.
- Experienced Divers – The dive should only be done with experienced cave divers who know the system.
- Checklist – Check all your gear before entry.
- Rope - Take the correct length of ropes and remove your rope on the way out.
- Rain - Check the weather to ensure no heavy rain is forecast. Similarly do not enter if the water is discoloured.
- Environment - Look after the environment. Do not touch limestone formations or remove rocks.
Riwaka Resurgence Schematic
