By Patrick Wiget 

After diving and instructing in several countries, I chose to improve my cave and technical diving skills by developing my techniques and adapting my configuration according to the environment, and familiarising myself with the different philosophies of other experienced cave divers and instructors. 

I opened a technical cave diving facility in the heart of the European caves in Sardinia 4 years ago where, with my business partner Thorsten, we teach programs according to the standards of recognised agencies like NACD, NSS-CDS, IANTD and TDI. I have learned to appreciate the various differences between our cave systems, which are located almost on our doorstep!  

The variety of the cave environments makes it necessary to adapt your dive plan, equipment, or techniques in order to execute a safe dive within a team! 

Caves along the Gulf of Orosei are accessed by boat and caves in the mountains of the nearby karst mountain chain (‘Supramonte’) are reached by car and rope support, giving Sardinia a unique position in terms of cave diving locations around the world. 

I would like to give you an overview of the specific environmental conditions you can encounter on the island of Sardinia!

Hydrogen sulphate is a substance that can be recognised by its ‘rotten egg’ smell. It affects the visibility and necessitates different communication procedures, team and environmental awareness, and guideline control. 

Haloclines are encountered in all our ocean-accessed caves that reach deep into the mountains. Haloclines also appear in a lot of systems in Mexico, and other caves where the fresh water from the inland hits the salt water level from the ocean. Salt water is denser than fresh water, and so light beams are diffracted when they pass through the halocline. This creates visual effects. A diver's finning motions will stir up the salt and fresh water like oil and water. Because of the impact on visibility, haloclines need to be understood and the team needs to shift properly on the line to supply the team members swimming or scootering at the rear with good visibility. If sediments get in the mix of fresh and salt water, proper communication and reel handling can be particularly demanding for the diver who has never experienced such situations.

Beginners appreciate the cave systems that have no flow, and an average depth of 35ft that allows a relaxed dive if desired. These dives include the opportunity for complex navigation, the discovery of the bones of animals that reach back 5000 years, and the possibility to surface to enjoy the stunning formations covering the ceilings and walls of the vadose areas. 

Search. Once you go out on the boat, the ocean can be rough and you will discover that finding a location for the primary tie off in open water and a safe location to exit the water can be demanding. The proper positioning of the tie off and knowledge of the water movements is the key to a relaxed dive under these circumstances. The diver and the team need to understand the water movements in order to place a tie off without losing a lot of energy while working or finning against the current.

Current can be encountered in several systems in Florida or the Bahamas where the tidal changes need to be considered, avoiding finning against the flow on the way in and out of the system! Depending on the season or tidal changes in Sardinia, the flow may need to be included in the air planning and calculations prior to the dive.  

Depths that reach down over 300 feet require complex gas planning and management. The staging of decompression tanks and dive rig management by the surface support team of ProTec Sardinia are an important part of the dive plan for the divers or the students taking a technical cave course. 

Navigation comes in to the plan when tie offs and jumps are made to explore the different side passages of the systems and to enjoy the circuits. The sumps are also quite an experience as the diver has to leave the water and hike through the cave until reaching the water again; alternatively the equipment can be placed at the surface to explore the cave on foot. Different considerations need to be taken into account when planning to leave equipment in the water or on the surface and to continue the exploration of dry passages! 

Sediments are a major concern while cave diving: gravel; sand; organic materials; mud and clay can all be encountered in our cave systems. Correct dive technique and good trim are essential, as they allow the diver to traverse passages where zero visibility can be encountered. 

Weather. When diving ocean caves, the weather has to be closely watched. When entering the cave, the ocean can be flat and calm, whereas upon exiting the weather could have changed and the primary tie off could be in an unsafe location. Our experienced staff monitor the weather forecast and know which cave entrances are accessible. As we have many different caves there is always an option that ensures a safe and enjoyable dive.

Side Mount

Excellent side mount diving can be encountered in the Sardinian caves and the full advantage of this configuration can be experienced.  Where restriction after restriction requires the side mount diver to remove the tanks in order to pass through the cave, this makes the side mount configuration a must! 

Stages 

In Sardinia, there are caves where miles of line have been laid and more passages wait to be explored. Here, stage diving can be enjoyed, involving both restrictions which require the stage to be pushed in front of the diver, and vertical passages where the trim and the balance of the diver is a major factor in enjoying a relaxed dive. 

DPV 

After the first year, we realized that the caves in Sardinia are much more complex and longer in terms of penetration distance than we originally thought. The DPV was the only option. From big caves with a diameter of 90ft to others that just allow the diver to steer the scooter through tubes and occasionally push it through restrictions, divers are given the opportunity to experience DPV diving with all its facets and difficulties.

CCR

Once the cave drops down to 120 feet and stays constantly at that depth for 2 km before a further drop to 180 feet, then a Rebreather is the right tool to use! A detailed bailout plan is of great importance and needs to be discussed with the team prior to cave exploration.

Explorations are performed in almost every cave system we have on the island. Some caves are virgin, and as there are not a lot of cave divers active on the island, once we are out cave diving we hardly see other divers! We are already laying miles of new line and exploring new passages.

Phreatic meets Vadose. We are working with the local speleological organisations in the mountain terrains, where over 2000 caves have been registered, and this gives us a wide variety of caves where the dry passage hits a phreatic area that needs to be explored. With the years of experience and know-how of the local organisations, we are able to execute tours into the caves and transport equipment vertically through the dry cave until the phreatic zone has been reached!