Friday, April 29, 2016

Blog Post: by Maxwell Fisher. 19th & 26th April 2016


Tuesday the 19th saw me diving at Porth Yr Ogof for the first time in 2016.
I had been monitoring the weather forecasts and River Mellte gauge levels for some time, hoping to get in. Finally time off work and weather aligned and I was able to make a trip over.
The water level was approximately one fin length (Mares Quattro) below the step; steady progress was made along the passage in light to moderate flow. 
Line abrasion from flow in the 'Pot'
The first point of note was the abrasion partway down the first pot. The sheath of the line was worn through, exposing the core which showed some signs of wear. I decided it wasn’t about to break on me anytime soon and continued surfacing in the first airbell. 
A quick check on gas pressures was made before I continued onto the next airbell. Again a quick check on gas pressures was made before continuing onto the upper cave water chamber. 
About 10m before the junction to Esser’s passage, some loose line was billowing down the passage. I continued on and saw that it was coming from the pot leading down to the rest of the cave. I continued along the main line and surfaced in the upper cave water chamber, the boulder slope easily passed in a wetsuit and 7l cylinders. 

I crawled through to the chamber proper and removed my fins and one 7l cylinder, keeping one on to pass the next short sump. This sump is quite short, at 4m long I would estimate and had crystal clear waters. A cobble slope restricts entry to one point. Surfacing in a section of cave I had not visited before, I dumped my kit and began crawling to find the next sump. This part of the cave is a wide bedding with a cobble floor. 
The next sump soon presented itself and I spent a few moments floating in it trying to glimpse what was beyond. Retracing my route back through the cobbles, I was soon kitting up ready to pass the short sump back. 
I had ample gas reserves left so decided to tidy up the line billowing out of Esser’s passage on my exit. I pulled it in hand over hand, coiled and attached it to the bolt above the pot to keep it out of harms way. It was clear that the belay at the bottom of the pot was intact, however I decided to leave that task for another day, riding the gentle flow of the cave back to the tradesman entrance.

After a quick sandwich I decided to have a walk up the dry river to locate the other entrances which I had not looked at before, some pictures are shown below:
Cwmbran Entrance

Cwmbran Entrance

Top Entrance

Main Entrance


I decided to visit again on the 26th to make repairs to the line, I planned two dives: the first to repair the pot line, the second to repair the Esser’s line. I had been unable to get a good fill in my 7’s, so decided to dive with a part full 7 and a part full 12 to give me plenty of time to fix the line in the pot. The flow was slightly lower today, the gauge level having dropped from 0.26m to 0.23m since my visit the previous week. 
Easy progress was made to the pot where I spent a good 10 minutes assessing before I made any changes. I examined the roof, finding a small air bell but no natural anchors to create a deviation from. I noted a flake near the bottom of the pot which I thought to be useful for holding the line away from the pot wall. I tentatively cut the old line and began attaching the new one working upstream so as to always have contact with the exit line. In total this dive lasted 32 minutes, I was very chilled on exit. 
A diagram of the current situation in the pot is shown below (side view):

The carpark afforded no warmth during lunchtime with sleet and snow showers. A chilly diver re-entered the water with the intention of fixing the Esser’s passage section. 
Easy progress was made using just about 1/3 of one cylinder leaving 1/3 of the second cylinder to work with, I removed my coil from the S/s bolt I had made the previous week and descended the pot, new territory for me. 
To my surprise three belays at the bottom of the pot were intact, the break in the line having occurred much further into the cave. Once at the bottom of the pot the rock belay is intact, moving along the passage a little further a lead weight belay was intact and further again the final intact belay was a thread in the right hand wall opposite a cobbly slot in the floor which I believe is Esser’s passage itself (?)
I had a large amount of rope in my hand at this point, having added to the coil to this point rather than reducing it and was fairly cold so I decided to exit and come back again to further explore this section of the cave. I was glad to get back to the surface, ditch my wetsuit and drive home with the heating on full blast.
A plan view sketch has been drawn of the situation: