SCUBAHUB
Safety notice and retraction – reservoir dive article
Regarding‘ Searching for Leaks … Got Potatoes’ published in SCUBA’ s June issue
WE WISH TO ADDRESS AN important safety concern arising from the article published last issue, in which members of a BSAC club described their dive in a local farm reservoir to search for leaks.
We wish to make clear that the club acted with entirely good intentions and genuine community spirit, and we commend their willingness to help. However, following publication we have been made aware that this activity presented serious risks that were not identified or discussed in the article, and we have a responsibility to our readership to address this directly.
As with all content in SCUBA, every submission is subject to review by the Editor and BSAC CEO. Despite several levels of checking, we failed to spot the serious risks detailed in the letter, a failure for which we now apologise.
The danger of differential pressure
Diving in or around reservoirs, water storage systems, or any body of water connected to pipes, inlets, or outlets carries a significant and potentially fatal risk known as differential pressure( DP). Where water is being drawn through any aperture— even a small crack, pipe, or breach— the pressure differential between two bodies of water can generate powerful suction forces. These forces can pin a diver against an opening with a strength that makes self-rescue impossible, even in conditions that appear calm and benign. Differential pressure incidents are among the most dangerous situations a diver can face, and fatalities have occurred in circumstances that seemed entirely manageable at the outset. The very leak the team were searching for had the potential to create exactly this hazard.
Activities involving differential pressure risk must only be undertaken by professionals with specialist training, appropriate equipment, and strict operational protocols in place. This is not a risk that can be adequately managed through standard recreational diving practices, however experienced the divers involved.
The importance of BSAC risk assessment approval
All BSAC clubs are required to submit a risk assessment to BSAC for any proposed project or activity that falls outside normal club diving. This process exists precisely to protect members— it ensures that risks are independently reviewed and signed off, and that appropriate insurance cover is confirmed to be in place before anyone enters the water. Had a risk assessment been submitted for this activity, the differential pressure hazard would have been identified at that stage, the activity in this form would not have been approved, and the appropriate guidance could have been given to the club. This type of activity is not covered under BSAC club insurance, and would not be covered for club diving as it requires commercial diving specialist expertise, equipment and protocols. We urge all club Diving Officers and committee members to remind themselves of the risk assessment submission requirements for non-standard activities. If you are in any doubt about whether an activity requires a submission, contact BSAC directly – it is always better to ask first.
To the members of the club
Your enthusiasm and willingness to help your local community is exactly the spirit that makes the diving community special. We share this notice not to criticise, but because diver safety is our shared responsibility, and we would far rather address a near-miss than report a tragedy.
A mystery to unravel in Portsmouth
A DIVING OPERATION LED BY BSAC MEMBER RILEY Conway has been launched to discover the identity of a ship that sank 100 years ago in Portsmouth’ s Langstone Harbour.
Believed to be the dredging vessel Withern, which sank in 1926 – the same year Portsmouth was granted city status – the wreck’ s identity has never been confirmed. The site has become a source of mystery because another dredger, the Witham, sank nearby in 1912 under similar circumstances. Both vessels were lost on their moorings in the harbour.
Historical accounts suggest the mystery wreck sank overnight without crew, leaving behind unanswered questions about how and why it went down. With limited archival information currently available, the Withern Project team hopes that modern underwater survey techniques will provide long-awaited answers.
For Riley Conway, who began diving in 2022 and recently joined the Nautical Archaeology Society’ s sub-aqua club, the project also represents an opportunity to‘ apply newly acquired skills in a real-world setting’.
“ This project is about more than just a wreck,” said Riley.“ It’ s about uncovering a piece of Portsmouth’ s history that’ s been lost for 100 years and sharing it with the community.”
The Withern Project is supported by a grant from Portsmouth City Council as part of the‘ Portsmouth 100’ celebrations of the city’ s centenary. Following their initial dives in April, the project team will return to continue their underwater investigations of the site later this summer.
“ As Portsmouth prepares to celebrate 100 years as a city, the Withern / Witham survey project stands as a fitting tribute to its enduring relationship with the sea – combining heritage, science, and community engagement to bring the past back to life,” Riley added.
The findings will be compiled into a detailed written report and shared with local stakeholders, including Portsmouth Harbour authorities. For more information on the Nautical Archaeology Society SAC, go to www. nauticalarchaeologysociety. org / dive-club
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