Post date: Mar 25, 2018 7:49:22 PM

Team: Petie Barry, Adam Prior, Adrian Bacaoanu

Time: 9 hours

Aim: Survey high level passages around Mistake Junction, have a look at Georges Choke.

After a bit of a lull in the surveying activity in Shannon it was time to get stuck in again, this time with with some fresh DCU blood in the form of Adam and Adrian. The plan was to survey the high-level passages running from Mistake Junction to Aghnahoo Chamber, and perhaps the phreatic tube explored back in 2007. I also wanted a look at Georges Choke, which currently needs a bit of tidying up to make it safe(er).

Arriving at Georges I stuck my head into the choke for a gander. The Steves, Claire, Aileen and Ezster passed through Georges in the summer while on the way to survey 10 Years Hard Labour, but some boulders shifted while on the way out and some running repairs were needed to get the rest of the team through. The word was that the choke was passable but there was a problem boulder that would need capping. Indeed the boulder would need removing and realistically 3-4 pieces of scaffold needed to cage off an unpleasant-looking load of hanging death. Plus concrete everything in sight (ideally). Job for the summer maybe.

After this recce we went up to the Orange Lodge in Aghnahoo Chamber for lunch, and then set off down through the chamber to find our passage. Just where the upstream end of Aghnahoo Chamber meets the water a crawl heads off upstream - after about 20m this emerges into a bouldery chamber, then a scramble over loose boulders leads into a larger chamber, and then another scramble up loose boulders leads into a larger chamber, then a scramble up loose boulders leads into an even larger chamber, then a craw through loose boulders leads into the largest chamber of all, 20m long, 8 wide,12 high.

At the far end of this chamber a climb up at roof level leads to a junction - continuing on leads after a short distance to Mainstream Junction (and possibly onwards to Pisstake Passage?) - and turning north into a narrow crouch enters the ‘phreatic tube’.

I didn’t have much info on this phreatic tube, except that it ended in a gaping pitch, somewhere above the stream. Also, I was expecting a literally circular tube - what we found was a 2m high by .5m wide passage which pinched in at top and bottom - ‘labial’ is the best way to describe it. After passing through some small breakdown chambers the passage ends where the tube pinches off at an impassable squeeze. Immediately beyond this squeeze the floor falls away into a large chamber, and a thrown rock seemed to fall a good 10m. You can hear the stream quite clearly here. It’s an interesting little passage - oddly intimate in scale compared to the other high-level passages in Shannon.

We shot the final few tie-in legs to Mistake Junction and made our way safely out. Always nice to have a Shannon trip without a scary boulder incident. Just over 200m was surveyed, Shannon is now 7.52km in length. Two good trips might finish off the stuff before Georges.

- Petie