One of Canmore's best-known caves is being remapped after new section found

Rat's Nest Cave is a provincial historic site on the south slope of Grotto Mountain.

Rat's Nest Cave is a provincial historic site on the south slope of Grotto Mountain

Tom Barton returns from a dive of the Grotto Sump. (Dave Thomson)

Cavers in Canmore are re-examining one of the area's most famous caving spots: Rat's Nest Cave.

The provincial historic site, on the south slope of Grotto Mountain, is being resurveyed after a new passage of the sprawling system was discovered.

"Just recently, some groups from the local caving club made some interesting discoveries," said Adam Walker, the owner of Canmore Cave Tours, and one of the cavers involved in the re-survey project. 

"Mostly it's just new cave passage. That's what we're always looking for. But one of these passages happened to have some beautiful cave formations — untouched, pure formations."

Charles Yonge sketching the cave map during some of the original survey of Rat's Nest Cave. (Dave Thomson)

The cave system was already one of Canada's longest and deepest caves, with four kilometres explored and documented so far, reaching depths of 245 metres. The last survey was undertaken in the late 1970s and '80s. 

"Along the way, you might find some new critters or even a new entrance to the cave, so there's all kinds of possibilities," Walker said. 

No 'scooping booty' here, thanks!

Walker says there are both official and unofficial reasons why one undertakes a cave survey. The official reason being that cave data like depth and length are wrong if a survey isn't undertaken. 

The unofficial reason comes down to a caver's ethics.

Walker says it's called "scooping booty" when cavers explore a cave that's undocumented without surveying it. It's "frowned upon" in the caving community to explore selfishly without leaving the information for future generations of cavers, he explains. 

How to survey a cave

The survey requires little in terms of specialty material. A tape measure, compass and clinometer are generally used, but now new technology — called a Disto X — allows for a more simple and immediate method. Even sketching on waterproof paper is going the way of the dodo, Walker explains, as both data and a sketch can now be captured on a smartphone or tablet.

With bluetooth connectivity between the Disto X and the smart device, they can see the 3D renderings of the new segments of cave while they are still underground. 

A laser distance measure configured to measure the compass bearing, inclination and distance of a cave in a single shot. The data is then blue-toothed directly to a smart phone or tablet where the cave map is drawn using a special cave survey app. (Adam Walker)

Resurveying the entire cave could take several months to a couple of years, depending on what the team of cavers find.

"We'll publish a map at the very least, so be able to show everyone what we've found and what the cave looks like. And who knows, we might be able to get some new discoveries published as well," Walker said. 

One of the bones found in the 'Bone Room' of Rat's Nest Cave. (Adam Walker)

With files from The Homestretch.


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