Diving The Gourneyras

PHOTOGRAPHS BY RICH STEVENSON

Thai cave rescue hero Chris Jewell joined Andy Torbet and Rich Stevenson for an exploratory jaunt to the cave systems in the Herault region of France

Many UK-based cave divers will be familiar with heading over the Channel to France to enjoy the delights of the large underwater caves and often excellent visibility which can be found in our nearest continental neighbour. Most divers head to the well-renowned ‘Lot’ region (a department in the Occitanie region of France) and the caves there see a steady stream of visiting cave divers from all over Europe enjoying the world-class conditions. The Lot, however, is not the only part of France with fantastic underwater caves. A few hours further south, the caves in the Herault are equally spectacular, if logistically more demanding. For those that preservere, you will be rewarded by sites less frequented than in the Lot, although you need to be prepared to work a little harder for your diving.

In an early January trip, myself, Andy Torbet and Rich Stevenson headed to the Herault to see what the area had to offer. As we knew we’d be a long way from the nearest diving centre, we ensured we’d be self-sufficient with our own compressor and gas booster and, as we’d all be diving rebreathers, that would also ease the burden on needing fresh gas supplies. Handily, Rich’s VW Transporter swallowed the large mountain of equipment which three self-sufficient cave divers require.

After several days of reconnoitring various other sites, we decided to visit a cave called the Gourneyras. Despite the heavy winter rainfall plaguing some locations in France, when our trio arrived at the large sump pool below a tall cliff face, the water looked clear and extremely inviting.

The cave is part way along a rough track which contours along the side of a valley. After 3km of steering the VW Transporter along the tricky road, a path down the short but very steep hillside led us to the valley bottom where the cave resurges into the river.

At the top of the path there was evidence of the tyrolean traverse which is normally rigged to lower gear to the cave entrance when large groups visit. However, with just three of us, and lacking the long section of rope required for the tyrolean, we decided to simply carry our kit down to the water’s edge for a short recon dive in order to check the cave’s conditions. Sturdy rucksacks, a pack frame, walking boots and several ropes fixed as ‘hand lines’ were essential to move the gear down the steep slope to the cave. However, after several journeys up and down, we had sufficient equipment to allow Andy and I to enjoy a dive while Rich stayed topside to take some photos.

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Some 45 minutes after leaving the surface and content with what we’d seen, we turned around and put the scooters on top speed for the run back to the entrance

We knew from our research that the cave sloped steeply down below the entrance pool and that very quickly Andy and I would be down at 60m only a short distance inside the cave. Swimming down the vast underwater tunnel, I was amazed at the dimensions of the passage. It is easily the largest underwater cave I’ve ever visited and, despite visibility in the cave being in excess of ten metres, it was frequently hard to see the walls in the huge submerged tunnel. After about half an hour of swimming, we reached a slightly shallower section of the cave at 40m, which we followed until the cave dipped back down again. Hovering at the precipice of the underwater shaft, I shone my light down into the enticing depths. I wanted to see what came next and I was already formulating a plan for a return the following day with more equipment.

We reached the bottom of the sloping entrance shaft after an hour in the 11 degree C water and looked up from 45m to see a blue glow created by sunlight hitting the large entrance pool. After another hour decompressing in sight of daylight, we surfaced to a sunny afternoon and an expectant Rich.

After such a great dive, I was excited by the prospect of going further into the cave, which would require some additional open circuit bailout and two of the scooters we’d brought with us. I had also brought with us a lightweight decompression habitat. We’d tested this at NDAC near Chepstow, but I’d never used it in anger in a cave and I was keen to see just how cosy we could make the 6m decompression stop. So, we hatched a plan for Andy and I to spend the next day rigging the habitat, while Rich had a quick dive to check out the cave for himself.

Entering the habitat

The habitat we were using is rather like a giant lift bag. Made of tough but flexible PVC, it can be secured to the floor and filled with air to create an underwater tent where you can sit out your decompression stops in relative comfort. Large enough for two de-kitted divers, it creates around 800kg of lift when full, so it’s critical to attach it to the floor of the cave very securely! In our case, we found two huge and very immobile boulders in the cave as reliable anchors. After assembling the habitat frame and bag, we attached each corner to a caving abseiling device (a Petzl Stop). This allowed us to make adjustments to the bag as we inflated it, to ensure the bag was level. We then filled the habitat to the rim with air and once we were happy it was secure, we left it overnight for the big dive the following day.

The plan was for Rich and I to go to the deepest part of the cave at 105m depth about 1,250 metres from the entrance. In order to do this, we each carried three open circuit cylinders in addition to our rebreathers and we each used a scooter (DPV) to tow us quickly through the flooded cave. Using the scooters, Rich and I quickly reached the point where we’d stopped on the previous dive and headed deeper after only a momentary pause to communicate that everything was okay.

We descended steeply back down to 60m again and marvelled at the size and beauty of the cave as we sped along, pulled by the small torpedo-shaped scooters clipped to our harnesses. With my hand-mounted light, I traced the course of the dive line as we zipped down the passage. The original explorers had installed this line when they first

The entrance to the cave

Chris prepping kit prior to the dive

visited this part of the cave, but over the course of many years it had suffered the ravages of multiple high-flow winter floods. Normally a cave line should be pulled taunt and well secured at frequent intervals, but here it was frequently hanging slack in large loops or spiralling off in odd directions only to zigzag back on itself. In several places, multiple lines ran forward where other teams had installed a new guide line but left the original in place. Sometimes we were following one line which would end abruptly, requiring us to search around and switch to an alternative parallel line.

With Rich in front we followed the sometimes chaotic dive line until abruptly it ended completely. Rich hung in the water ahead of me in a spacious chamber while below him the cave plummeted downwards to where our lights barely picked out the cave floor and walls. From the map of the cave I’d seen, I knew that below me was the deepest part of the cave at around 105m. We were at 65m depth and the floor was somewhere 40m below me, but there was no guideline in sight.

A rebreather mouthpiece allows you to talk with a little difficulty and so with the effects of helium making my voice squeaky and high pitched, I said: “Where’s the line?” By response Rich shrugged and it was clear that we’d need to install our own line if we wanted to go any further.

After unhooking my reel I found a suitable point to tie into and with the scooter on slow I began spooling out line as I slowly descended in mid water. I pointed my torch down trying to pick out the cave walls and floor as we headed into the abyss while keeping one eye on my rebreather PPo2 and

Large enough for two de-kitted divers, it creates around 800kg of lift when full, so it’s critical to attach it to the floor of the cave very securely!

feeling the ‘ADV’ injecting more helium to counter the effects of descending. Below me, the cave floor appeared and with it another section of the original dive line. At 90m I was able to stop and tie the new line I was laying into this one and after a quick ‘okay’ to Rich, we carried on down. By scootering above the line in the deepest section we passed the elbow of the sump at 100m depth and began a steady climb up the far side. We let the scooters bring us slowly up the far side of the deepest part of the cave. At 80m depth, we were now about 1,300 metres from the cave entrance and approaching our agreed turn point. Rich held his thumb and index fingers out together to me to say ‘just a little further’ and another 50 metres later we reached the head of yet another shaft heading back down to over 90m, which signalled our turn point. Some 45 minutes after leaving the surface and content with what we’d seen, we turned around and put the scooters on top speed for the run back to the entrance. At 39m depth, the series of long and slow decompression stops began. At 21m we picked up the EANx50 bailout cylinders and moved them with us until at 12m, Andy appeared to relieve us of the extra cylinders and scooters we no longer required. Then at 6m, Andy was able to assist me out of my rebreather and into the decompression habitat.

Being a small lightweight habitat, it’s only possible to sit in it after removing all your equipment. This is a delicate operation and if anything goes wrong, you could end up on the surface rather too quickly. Once settled into my comfy capsule, it was noticeably warmer and I could eat and drink. Rich stayed outside taking photos and then put his head inside the habitat so that we could talk about the dive. Like me, he was wishing we had one more day of our holiday left so that we could go back and see what happened next! n

Heading into the system

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