Dower Bridge Rising, 27 - 28 October 2022

Thursday 27^th October 2022

Divers: Hugh Norton, Josh Bratchley

Gear:

• Hugh: 2x7L @ 240bar each

• Josh: 2x5L @ 200bar each

We both kitted up in the river and walked up to the entrance chamber where the two major abstraction pipes terminated. The water at this point was crystal clear. It was decided that I would dive first. Checking all 3 of the rifts in the chamber the left looked the most promising and I could see some orange polyprop line at the bottom of the rift.

Tying my primary line off to a steel beam I descended and investigated the condition of the orange line. It appeared to be in good condition and well belayed so I tied my reel off to it and followed the in situ line. The passage quickly Descended to 8.5m, the deepest part of the cave. The ground here was very silty and difficult to stay above as I had opted not to take a buoyancy device with me and was slightly negative at this depth. With the good vis I was able to follow the line past a junction with what looked like thin line coming from the right, this is assumed to come from the right hand rift at the surface.

Continuing North through an area with a low ceiling, the line eventually surfaced in the 1^st airbell, the prospects in this airbell did not look good enough to get out of the water for. Here the line colour changed to blue polyprop. Continuing through a short slot at about -2m the 2^nd airbell was reached directly North of the first Airbell. The way on from this airbell was through a hole in the floor on the right hand side. This descended to a roughly 3x3m chamber and the way on continued through boulders until a 3^rd airbell was reached. This airbell is probably the largest so far but with no above water floor.

From the 3^rd airbell the line changes to white braided nylon before continuing in a northerly direction dropping back down to 5m where a finger spool attached to the line warns of a restriction. The restriction is tightest on the right hand side going in with a silt floor on the left where it is more spacious. After the restriction was passed the line changes to some extremely thin red baling twine which went through a large 2m high silt bank. Thankfully at the end of this silt bank the line changed to normal blue polyprop again and after going under a ceiling went through another 2m high silt bank. A possible continuation over a third silt bank but the line ducked under another ceiling and was terminated tied to a boulder under some silt.

The passage looked like it continued straight on through a low ceiling passage with a Silty floor. I cursed myself for not bringing a second reel to explore with. The descriptions of the cave I had read made it sound like it would close down fairly soon, and here I was after over a 100m of straightforward enough cave diving with open passage for the taking and no reel!

I turned the dive and made my way back out, the vis was still fairly good providing I stayed in front of any silt I threw up. The silt in this cave seems to have reasonably good surface tension and doesn’t get disturbed by fin strokes, only when you physically disturb it. Still large particles were suspended in the water throughout on the way back.

On surfacing I told Josh to take the reel and go add some line.

Josh took my other reel with that was sitting on the pumping station walkway and did his dive. He tied the line in to the end and laid roughly 10m down the silty low passage with it still continuing. He had to turn the dive due to reaching thirds and being too negatively buoyant which made laying line in the silt difficult. It was noted that the strong flow that could be felt at the entrance was not present where the line ended.

The descriptions in the Sump Index and in the Caves of County Cork did not match up with what we had just dived, neither made it sound like there was great prospects in the cave. We would be back the following day.

Hugh

Dive Time: 21 minutes

Max depth: 8.5m

Friday 28^th October 2022

Divers: Hugh Norton, Josh Bratchley

• Gear

  • Hugh: 2x7L @ 240 bar each, 1x3L @ 240bar

  • Josh: 2x7L @ 200 bar each, 1x3L @ 240bar

We decided that I would dive first as I was heavier on gas and wanted to lay some line after the day before. On walking down to the river bank it was discovered that the crystal clear vis from yesterday was gone and the water had a milky quality to it. There was a good bit more flow in the river as well. The heavy rain from 3 days ago had made its way through the cave.

I decided to go ahead with the dive anyway and even if I didn’t reach the end of line it would still be worth going in and fixing up the line where it needed some TLC. Armed with plenty of silt screws and snoopy loops I headed in, making minor adjustments to the line as I went. The vis was just short of 1m but I was able to make surprisingly good progress. Stashing the 3L just before the 1^st airbell I continued on and reached the reel at the end of the line.

I picked up the reel and continued on laying line for another few meters until I reached my thirds. Following the left wall of the passage the silt started giving way to rocks in the floor which I tied my final belay to. At this point the depth was about 1.3 and the ceiling above me was a rift. The flow was also evident throughout the dive including at the end.

Dive back to entrance was uneventful in poor vis.

Josh then kitted up and did his dive. Diving to thirds he was able to lay another 15-20m of line where he was able to confirm that the passage was now in a rift that was getting narrower and back down to a depth of -5m

The passage is still ongoing and will require a return trip to both survey and reline sections in order to remove line traps and bailing twine.

Hugh

Dive Time: 29 Minutes

Max Depth: 9m