An opportunity for a break from the treadmill of Notts Pot was presented when Peter Glanvill (of Mendips Doctor fame) offered me a place in his Volvo for a week-long trip to County Clare, Ireland. Those familiar with the area will recall the typical endless winding canyon passages to be found in most of the popular caves. Caving in such passages can become monotonous, however, this trip was to prove different and shed a 'new' light on County Clare caving.
The principal aim was to explore further the Green Holes off Doolin point, but also included in the plans were some interesting bad weather alternatives. Plans were altered on arrival because of the need to time a Green Hole dive with low tide. The lure of the alternatives became greater, so that more time than was envisaged originally was devoted to exploration inland.
The third cave, Tomeens, was the climax to this day of easy caving. A large well-sculptured river passage with a cross-section of 7m by 4m opened out to daylight at various points along its 400m length. The overhanging vegetation added to the atmosphere and Mark's Hasselblad was used to good effect. The local kids were amazed at seven adults enjoying a paddle along the river's underground course.
The recently discovered Poul na Gleim produced another day's entertainment. Found in August 1985, it drops to a sump at -74m with little horizontal development - almost unique in Clare. Brian Judd had passed four sumps to reach two more pitches, the second of which was undescended. He was trying to recruit additional divers. Everyone was discouraged when he reckoned Pete would not fit through the fourth sump. I volunteered to go, but with some trepidation. A late start after feeding Brian's cows, collecting rope from all over the Burren, and a crash between two cars in the convoy heading for the cave (all of which typify the Irish attitude) eventually saw Brian and myself passing the sumps with a multitude of gear, including a Molefone. Apart from radiolocation, this was later to be used to give a running commentary on the exploration to the surface party. A new development for the armchair caver !
The passage dropped steeply between the short sumps, the fourth one necessitating hand held bottles to pass a boulder squeeze. A rope was used to haul through the tackle bag. The undescended pitch was quickly reached and bolted, but below, things looked uninspiring. Having relayed this over the molephone, the number of surface crew diminished drastically. A tight thrutch and a few climbs in the narrow, steeply descending fault passage led to a third pitch of about 17m. Below looked promising, and while rebelaying 7m down, news was again relayed to the surface. At the bottom, although over 3m wide, the walls were muddy. Beyond a large wedged block, the roomy Sump 5 terminated the passage. Above, an inlet waterfall looked unscaleable.
An exit through the sumps was made to meet Dave Gibson, who was on a visit to the Judds. He had arrived just in time to lend a hand with detackling, thus ending an eight hour trip. John Macnamara, who runs the local compressor, was the keenest over the news of sump 5, thinking that being cave divers, we were deliberately seeking more sumps.
Poul na Gleim is now 124m deep, the deepest in Clare, and has the potential for a further 120m down to the sea. The Pollnagollum-Poulelva system is the second deepest at 100m.
A day was taken on a visit to the Gort lowlands where large rivers continually rise and sink along their course. With one exception, they have not been followed. Coole Cave is an abandoned river passage ending at a sump which was passed in 1983 by Martyn Farr to another sump. The cave is slightly higher than the present river level, so it offers the chance of further dry passage. A two metre diameter tube, containing a few formations and gour pools, runs just below the surface, then descends to a sump floored with an extremely fine river silt. The thirty metre sump ends at a difficult climb to a tube which after forty metres descends steeply to a lake. A bolt was placed and a ladder used to gain the lake. Twenty metres across this, the new sump led off, to surface after 23m in a large rift with flowstone cascade. The continuation sump was followed for 16m until the 65m of line laid from the ladder ran out - a pity more was not carried.
At the invitation of the Johnsons, who own Ailwee show cave, I dived the sumps situated at the end of the cave. Although the silt banks around sump 1 were very low, only 66m of progress was made in the second sump. This is 6m further than previously reached - further extension seems unlikely. The fine main passage, known as "The Highway", made up for this, and again the Hasselblad was put to use. The delights of the restaurant were to follow, courtesy of the Johnsons.
The first dive was to Mermaid's hole which had been dived previously for a distance of 100m to a rising rift. Unfortunately, this had proved too tight with back-mounted bottles. As it was now trending inland and rising towards the end, expectations were high about reaching airspace. Brian Judd had even dreamt about a Mermaid's grotto at the end, hence the name. Entry was made by jumping from the cliff with little regard for the return. Descending to -10m, a huge entrance 4m high by 6m wide was seen in the crystal clear water, along with some large crabs. Brian laid line while I followed, belaying it to chert nodules. The water, although clear, had a distinct haziness, possibly indicating the mixing of fresh and salt water. A large passage to the left was passed after 30m, but was left for another day. The main route continued 3m square. After 100m, the rift was encountered, and about 10m of sideways progress led to Brian with his head in airspace.
Only just managing to surface enough to hold a limited conversation, it was evident that the passage did not go, and that there would in fact be no airspace at high tide. No swell was obvious at the airspace, but upon surfacing outside the cave, it had increased noticeably, making exitting from the water tricky. Brian was washed face down onto a narrow ledge and was unable to move until aided by myself. But I was definitely hooked on Green Hole diving.
On a later dive from the reef at the harbour side of the point, where I was unfamiliar with the location of the entrances, things didn't go so well. I became detached from the others on swimming out and disorientated underwater. The heavy swell, felt even at -15m, didn't help, so I abandoned the dive without entering any holes.
A final dive on the last morning, in perfect conditions, located the entrances to Green Holes entered earlier in the week by Pete. In between posing for photos I entered Harbour Hole, and 40m in picked up the line reel. I laid a further 5m to a squeeze, where cold, due to a leaky borrowed drysuit, forced a retreat. The line was wound back in, shaking off the many brittle stars that had become attached to it in the space of two days.
A little further along the base of the underwater cliff at -11m was Chert Ledge Cave. This was followed to the end of the line at a sharp bend. Upon exitting, a line of exhaust bubbles could be seen rising from joints in the rock above the cave, clearly showing that it trends under the reef.
A lot of diving remains to be done at all sites along this coast to locate other Green Holes. Doolin just happens to be the most readily accessible. Standard cave diving equipment and techniques are used with the addition of an ABLJ. As an approach to the 'sump' is made underwater, it should be ensured that there are enough air reserves for the swim to shore. It may be an idea to work on the thirds rule from the start of the dive. One notable difference from cave diving in Yorkshire is the clarity of the water and the much more varied and prolific flora and fauna which creates a very scenic dive.
A full exploration and survey of those Green Holes under the reef could reveal that they are in fact a network of connected passages, and could, like Mermaid's hole, contain a passage heading inland. This would produce some very interesting diving. Other NPC members are now showing an interest in a follow-up trip to dive this coastline.