THE GREEN LAKE
Marble Arch -Prod's Pot/Cascades connection Part I
Like all good things everything started in a pub. It was a Friday night in Frank Eddies in a border village of Blacklion filled the evening with usual potholing banter.
I went to take a leak and when I came back I heard someone talking about some mysterious green lake in Marble Arch System (4.5km ), possibly a sump, which could connect to another big , 4km long cave system, Prod’s Pot - Cascades. My eyes were getting bigger and bigger as he continued : the pool was attempted only once, by Tim Fogg, but the way on was lost in zero visibility. At that stage I already knew where I wanted to dive next. The next morning the jolly party of six proceeded to the Green Lake in Marble Arch Cave.
We entered the system through Lower Cradle Hole, negotiated the infamous Ducks and strolled along the impressive show cave for another few hundred meters until we reached the Skreen Hill sump. To reach the point of our destination, the Green Lake, we had to take a dry bypass route, which proved to be quite arduous with heavy gear. At the arrival we saw a large pool of water , radiating invitingly with a green glow. We arrived to The Green Lake.
I have a tendency to following the bottoms of sumps rather than their roofs and this time wasn’t different (without buoyancy I didn’t have much choice either). Over the first 10m the floor dropped gradually to -7m and lack of buoyancy started making this whole adventure somehow interesting. Nevertheless a visibility ahead was very good, around 2m, and to my surprise I realised I was in a big, couple of metres wide underwater passage. I continued for another 15m to the point where everything indicated that I was on the bottom of some vertically walled pot so I leaded the line and started ascending ( or rather underwater climbing up) At -2.5m my line ran out and at the same time the way up started getting tighter. With visibility quickly deteriorating I concluded that further ascent without a line would be daft so I cut it off from the reel and turned back.
Diver: Artur Kozlowski
Support: Ian Wilton-Jones
I have repositioned the line from my previous dive as I spotted some more promising place to ascend. It proved to be a good move and I surfaced in a surreal, 10m long canal filled with the long straws hanging from the roof which was only metre above the surface. I checked my compass: the canal was heading NNW. Good. Anything North was good. North meant Prod’s- Cascades….
The way on seemed to be situated somewhere under the water but I must admit, I wasn’t at my best on that day. A few hours earlier I had a close shave in Shepton Mallet Sump 2 and I must have been still a bit shaken. Not able to find any reliable belay point I called the dive.
Diver: Artur Kozlowski
Support: Ian Wilton-Jones
Unaware of the heavy storm that rolled over Blacklion on Friday night we pondered over swollen Sruh Croppa river flowing violently under the Bridge. The first duck had about 8 inches of airspace while the second only 5 inches and most of the route was out of depth (in normal weather I can tip toe all the way long). Some swimming was also necessary to reach the start of the bypass. Once there, usual bollocks with gear carrying followed, my big reel proving the most awkward. Big disappointment at the arrival to the Green Lake, which wasn’t green anymore – tea with milk would do it a better justice. Under water the vis was minimal, no more than 10cm but it didn’t really bother me – I quickly surface in my fairytale canal. Diving from its other end I surfaced in a smaller parallel canal but that was it, there seemed to be no other way on, or I couldn’t locate any in the limited visibility. I returned to my vertical line and dropped back to the bottom at -8m. I was ready to turn the dive. What else could I do? The vis was nil and my best bet – the canal - turned out to be a blind alley. I started to believe that the whole sump was only one big blind alcove.
I’ve lost my mojo but at the same time the other, familiar feeling kicked in: I knew that If I didn’t do something I would be regretting it forever. For my own peace of mind I deployed my 100m reel and attached it to the bottom belay point making a three way junction. Unable to read the compass I took the NE judging from the known direction of the previous leg and off I went. It was a desperate venture, against my own instinct.
Not surprisingly, after 10m or so I hit the wall finding myself in some tight alcove.
Out of alcove, slight modification of the course and slow, painstaking progress ahead, whatever direction it was. Despite my efforts to stay out of the soft, muddy bottom the vis was still non existent. The roof must have been quite low there, no more than 50cm, as I hit it a couple of times with my helmet. I belayed the line with a silt screw and continued, the fact that actually surprised me the most - the passage continued to somewhere!
A gradual change in my buoyancy indicated that I was ascending and at some point the noise of my bubbles breaking surface somewhere above suggested that I might be already in an open water. I allowed myself a brief moment of excitement but this was quickly dashed by realisation that most likely, in that whole confusion and non vis business I was back to the Green Lake. I managed to read my bottom timer, -2.5m, and continued up the gentle slope. Finally I broke the surface in a large, 5x7m sump pool. I was still too disorientated to tell if it was the Green Lake or not, so I said out loud: Ian? No answer. A muddy slope continued above the surface and I shone my torch there. IAN?! I asked again but much louder. Again nothing. Small ripples on the slope created continuous pattern, seemingly undisturbed by any previous human presence. IAN!!! I shouted checking the compass at the same time. And then I knew he wouldn’t answer. I was facing North which meant I’d just discovered a dry virgin passage 40m behind the Green Pool sump heading towards Cascades…
I explored the passage for about 30m and found small stream flowing from the North into the sump pool. Due to the lack of proper equipment to explore a dry passage and the fact that Ian was waiting at the Green Lake I didn't move any further. The passage continued.
If connected, the Marble Arch System (4.5km) and the Prod’s Pot – Cascade ( 4km) would constitute the longest cave system in Northern Ireland and the third in Republic and NI , after Pollnagollum and Doolin Cave, both in co. Clare.