Page 16 of 24
After much discussion on the merits of diving in Vietnam an attempt was made in 2007. Unfortunately the logistics of transporting air without the facility of a compressor proved to be the undoing of the trip. Whilst charged cylinders had been sourced from a dive centre in the Ha Lang bay area from where they were sent down to the team by train, however cylinders have to be empty for transportation on Vietnamese trains. Unknown at the time the disappointment was obvious when the team collected their cylinders only to find them empty.
For the 2009 trip a number of options were explored which included transportation of the dive centre cylinders by a hired vehicle or taking out a compressor from the UK. The downside was the limited fills available by decanting and weight and associated costs of shipping out a compressor. The decision on what to do was finally made easy when Jon Simms was identified as a potential team member due to living in China and owned a compressor that could be transported via train. A few emails and telephone conversations confirmed the latest recruit to the team.
In order to bring the compressor still required some work to ensure it cleared customs, however this was all sorted thanks to the tireless help of Mr. Hieu.
For this trip the diving part was still very much a Recce with the primary objective the Inlet sump in the upper Cave of the Hang Vom system. The significance of this was that the source of this inlet is unknown with a large area of limestone providing great potential. Other sites dived were the resurgence of the Chay River and Noise Cave which is found above the Chay Resurgence. The Chay resurgence is a major resurgence again the source of water unknown but no major cave has yet been found in the possible catchment area on the North side of the river.
The Chay Resurgence is an inviting Blue pool and which provided a good place to test equipment and dive together since it had been over 10 years since our last dive together. The pool has an average depth of -10m with the water powering out of a number of rifts and boulders. The only passable passage was a rift in the left side of the pool. Almost immediately the passage was obstructed by boulders. Route was attempted over the top but could not be negotiated due to the force of water. An attempt under the boulder s proved successful and entered a large tunnel that dropped steeply. This was descended to a depth of -35m and approximately 50mof line laid. Due to the small cylinders, limited visibility and the passage still going deeper the dive was terminated. Future dives here would need to be geared up for a potentially long deep dive. Whilst kitted we examined a second pool kindly located by the support team. This was a static pool 200m upstream and on the same bearing as the resurgence passage, it was hoped this could be a window into the main cave. Unfortunately no way could be found as the heavily silted walls soon turned visibility to zero and the pool was full of jungle debris including fallen trees which made route finding impossible.
Noise cave is found almost directly above the Chay resurgence and was discovered in 2003 a little over 400m long with the cave ending at an upstream sump. On the day of the dive the current was alarmingly strong and difficult to swim against. The sump was soon passed after only 15m into a large sump pool forming a 3 way junction. Following the downstream flow of water to the left the flow of water was soon lost and static pools were crossed until a chamber was reached with no way on. The pools were examined with a mask but no obvious passage was seen. Attempting to follow upstream at the 3 way junction proved a challenge. The passage narrowed to 1m with the full force of water. Progress was impossible despite a combination of wading, swimming and pulling along on the friable handholds of the passage. A return would be best done when water levels are lower.
Hang Vom inlet sump is found close to the upstream entrance of the upper cave. Visibility for the dive was almost zero due to
recent heavy rains. The sump was passed after 30m into a chamber and a massive boulder choke with no way on found.
Future prospects for diving are sure to be successful however the major river caves will no doubt present challenges in the form of low visibility and depth not to mention the remote nature of some of sites. The smaller caves will be more appealing for small lightweight teams with limited equipment. The trip was affected by significant rainfall which affected flow and visibility which would need to be taken into account on future trips.