DIVING RATHLIN By Geoff Hide
One of the most spectacular and varied dive sites available to the diver is Rathlin Island. Rathlin lies some 10 miles off the North Coast of Ireland, guarding the Northern approaches to the Irish Sea. The Island is less than 7 miles across and it is here that divers can find spectacular cliff dives, wreck dives, drift dives and, of course, a pub!
Ferocious tidal streams rip, unpredictably, around the island making dive planning a bit tricky. The North side of the island is faced with underwater cliffs which descend to depths of over 100m.
It was with all this in mind, that a number of us from Edinburgh University Sub-Aqua Club decided to go on an expedition to Rathlin Island. Sarah McCracken, Ingrid Baber, Mark Inall, Kenny Jack, Graham Russell and myself participated.
Our first dive was an evening warm up dive on the wreck of HMS Drake. The Drake sank on the 20th October 1917 after being torpedoed by U79. The 14,000 ton warship was subsequently salvaged and blown apart by the navy. The wreck lies in 18-20m of water and with little in the way of tidal streams makes an excellent but not too demanding a dive. The wreck is very broken up although some large pieces remain and it is possible to grub around underneath some pieces.
The next day we set out in our inflatable around to the far side of the island to dive the underwater cliffs at Skerriagh Point. The effects of the excellent local Guinness the night before was made apparent by our subdued behaviour! We dived Skerriagh Point on slack water, as we felt it appropriate to assess the sites before attempting any drift dives in the wild tide races which are a feature of this area. We dived just off Skerriagh Point to discover a steep rock slope, festooned with marine life, to 45m and from then on a cliff dropped away vertically below us. For our second dive we travelled further around the island to Farganlack Point. The diving off this point was even more spectacular than Skerriagh Point. We swam down a rocky slope to 20m to find a sheer drop off. We followed it down to 40m, where it seemed to continue endlessly. The rock face was again covered with marine growth.
We moved back to wreck diving the next day with two dives on the wreck of the ss Lochgarry. The Lochgarry was a luxury MacBraynes steamer which was requisitioned during WW1 . This 88m long, 1400ton ship piled into the Mull of Kintyre on the night of the 21st January 1942. She drifted across to Rathlin and sank with the loss of 23 lives. Slack water is essential to dive this wreck.as the tides are very unpredictable. The wreck itself is very intact and the ships holds are filled with large chains, whose links are some 0.5m across. These were placed here by the navy to restrict access to large quantities of ammunition which are still on the wreck. Near the stern of the wreck, the decking is tiled in black and white, an indication of the wrecks former glory as a luxury steamer.
Almost certainly, one of the best dives of the expedition we did the following morning. The Santa Maria was a 5000 ton American tanker which was torpedoed in 1919 and sank off Fair Head. She lies on her starboard side in 70m of water. The port side being in a depth of 50m. Apart from the depth, the major difficulty with diving this wreck is that only 20 minutes of slack water occurs each day. A local skipper took us out to the wreck in his hard boat. We arrived well before slack water, kitted up, and waited until the buoy popped up. The dive we had planned was a 10 minute dive at 57m to go and have a look at the huge, four bladed phosphor bronze propeller. We were expecting our computers to give us some 5-8 minutes of decompression stops for this dive. We waited and waited and then, finally, the buoy appeared. After confirming that the water was indeed slack, we all leapt into the water simultaneously and scurried down the line at a speed approaching 30m/minute. We arrived at the port side of the wreck in less than 2 minutes and set off swiftly for the stern. The visibility was tremendous and we could see the seabed below us at 70m. The line was attached to the bridge area and we swam back past two holds to the stern accommodation area. As we raced aft, we passed loads of portholes lying on the port side of the ship. Finally, the huge prop loomed out of the gloom - it was a spectacular sight. A quick look at our computers showed the seconds to be ticking by, we headed back towards the line. Six divers arrived simultaneously at the line and headed up to carry out decompression stops. Following a 1 minute stop at 12m, we moved up to 6m to wait until our computers cleared. As we waited, we had visions passing through our minds of the tide building up before we had completed our stops. It was quite a relief when, 16 minutes into the dive, the first computer cleared. The others followed suit within the next 2 minutes and we completed a further 3 minutes of "safety" stops before surfacing. On the surface we could see standing waves advancing around the headland and within five minutes the buoy began to disappear as the tide built up. During the boat journey back we were all very high and plans were formulated to repeat this dive the next day. In between the two dives on the Santa Maria, we also carried out shallow dives on a boulder slope at Black Head and a very broken up wreck, the Girvan.
For our next days diving, we headed off around the North side of the island to drift dive the cliffs. Our first dive was to 40m on Derginan Point, which as we were soon to discover, never has any tidal streams. However, the dive was tremendous as the cliffs were topped with pinnacles and archways. Our second and third dives were carried out at Farganlack Point to depths of 35 and 30m. This time the tide was racing and we had two exhilarating dives "flying" along the cliffs. In one or two places down currents threatened to carry us below our planned depths and this added to the excitement of the dives. On the penultimate day of the trip, we did a further 2 dives on the Lochgarry. By this stage in the week, we were adding a couple of minutes extra decompression stops to most of our dives as we felt we might be pushing our luck a bit. Our final dive was based from the mainland. We dived Carrickmannon rock, a large shoal which rose from great depths to within 5m of the surface. The shoal had a smooth, steep rocky side which we followed down to 45m. We had planned to dive to 50m but after experiencing quite strong down currents at 45m we decided to call it a day there. The trip was a tremendous success with some brilliant diving.
Authors Note: The sequence of dives carried out on this expedition involved a considerable amount of repetitive and very deep diving. Decompression computers were used to calculate decompression requirements. Although no decompression problems were encountered, I feel that, in the light of recent improvements in our understanding of decompression, a sequence of dives such as that carried out on this expedition may incur a considerable risk of decompression sickness. Were we to repeat this expedition, we would reduce the frequency and depth of diving and include a day sight seeing in the middle of the week in order to reduce this risk.
©1997 SCOTFED - The Scottish Federation of the B.S.A.C
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