The Magazine for Underwater Professionals
An international team of maritime archaeologists are diving, excavating and recording the wreck site of Dutch ship Rooswijk off Britain’s Kent coast. They are excavating the storage rooms and living quarters in the stern of the ship and items such as large wooden seaman’s chests, pewter jugs and spoons, glass bottles, ornately carved knife handles and personal items such as shoes have been recovered from the wreck and brought to shore at Ramsgate where they are being conserved.
The Rooswijk was a Dutch East India Company (VOC) vessel which sank on the treacherous Goodwin Sands, off Kent, in January 1740. The ship was outward bound for Batavia (modern-day Jakarta) with a large cargo of silver ingots and coinage on board. Now a protected wreck site, the ship’s remains are owned by the Dutch government and managed by Historic England on behalf of the Department for Digital, Culture, Media and Sport. The #Rooswijk1740 project is led and financed by the Cultural Heritage Agency of the Netherlands, as part of the Dutch Ministry of Education, Culture and Science.
The Rooswijk is threatened by currents and shifting sands and an exploratory study of the wreck last year cemented the urgent need for the current excavation. The site is classed as ‘high risk’ on the Heritage at Risk register due to its exposed remains and vulnerability.
Alison James, maritime archaeologist at Historic England, said: “Wrecks such as the Rooswijk are time capsules that offer a unique glimpse into the past and tell a story. Sharing that story with a wide audience is a key part of this project and we look forward to the fascinating insights and discoveries that the Rooswijk excavation will uncover.”
Martijn Manders, project leader of the Rooswijk excavation and maritime heritage programme manager at the Cultural Heritage Agency of the Netherlands, said: “The Goodwin Sands has been a treacherous place for ships throughout the centuries and is now a treasure trove for archaeologists. It is also popular with sports divers. The rapidly shifting sands mean that the site is even more exposed now than it was during our initial dives to assess the condition of the Rooswijk last year. This makes the excavation urgent.”
There are a total of 250 Dutch East India Company shipwrecks, of which only a third have been located. Never before has a Dutch East India Company wreck been scientifically researched or excavated on this scale.
Material recovered from the wreck site is being taken ashore to a warehouse in Ramsgate where first-aid conservation will be carried out and the items fully recorded. From here finds will be taken to a Historic England storage facility where work to assess, analyse and conserve them will take place. The finds will be returned to the Netherlands and in future some material may be made available for display in Ramsgate.
A specialised piece of underwater scanning equipment has been used to locate and identify World War Two ‘bouncing bombs’ in a Scottish loch.
GSE Rentals, part of Unique System UK, provided the scanning equipment and engineering support to produce sonar images of the seabed at the dive site currently being explored by the British Sub-Aqua Club (BSAC).
The scuba divers have completed a mission to raise two historic Highball bouncing bombs like those used by the Dambusters squadron on the successful raid of the Eder Dam. Footage of the Highball bombs being tested was used in the World War Two film classic The Dambusters.
The iconic Highball bombs were recovered in perfect condition by the divers.
Mike Osterberger, senior engineer at Unique, said: “We are pleased that the quality of the images allowed us to identify not only a debris field with a number of Highballs but additional debris that we believe to be side charges from an X-Craft type submarine.”
The scanner was pulled by a workboat from fellow Scottish company Aspect Surveys. Sub Sea Tooling Services, also based in Scotland, provided an ROV to assist with filming the searches.
Around 200 Highballs have lain at the bottom of Loch Striven in Argyll for almost 75 years since they were tested by the Royal Navy for use against enemy ships and for the Eder Dam raid in the Second World War.
The bombs, which are inactive, were secured by the divers ready for lifting by the Royal Navy and then winched to the surface before being packed, ready for transport in wet tanks containing a special saltwater solution to prevent them from corroding.
The recovered artifacts will be put on display at the Brooklands Museum in Surrey, UK, and the de Havilland Aircraft Museum in Hertfordshire, UK, in time for the 75th anniversary of the Dambusters raid in 2018.
UK-based submarine rescue and diving equipment company JFD, part of James Fisher and Sons, reports it has facilitated a dry hyperbaric welding trial for Subsea 7 within its saturation diving complex in Aberdeen, Scotland.
“Ten diver welders were welcomed to JFD’s National Hyperbaric Centre and were accommodated for 13 days at a depth of 43 metres within the saturation diving system in order to prove their welding techniques prior to fulfilling an offshore contract,” said a spokesman.
JFD’s National Hyperbaric Centre houses the only land-based saturation diving system in the UK. “The 16-man saturation dive complex is the ideal choice for clients looking to simulate a realistic, controlled hyperbaric environment in order to pre-qualify their diver welders prior to an offshore project ensuring welding procedures are safe, compliant and efficient,” said the spokesman.
The saturation system is capable of facilitating manned trials to 300 metres and comprises two fully fitted eight-man living chambers which connect to a transfer chamber (TC). Wet or dry diving trials can be accommodated and in the case of a wet trial, the TC simulates a diving bell complete with moon pool which connects to the work chamber below.
The work chamber is fitted out prior to the weld by JFD’s technicians who ensure the correct safety and monitoring equipment is in place. Working closely with the client they create a habitat environment as similar as possible to the one in which the divers will be working in offshore.
“The dive follows exact offshore procedures with divers being monitored 24/7 by JFD life support supervisors and technicians as soon as they are under pressure,” explained the spokesman. “On shift within the work chamber, divers are monitored by Subsea 7 dive supervisors as they complete their welding procedures. Between shifts, the welded pipeline sections are removed from the work chamber through the entry lock of the TC and are taken away for inspection by a third party to ensure weld integrity in order to successfully qualify the diver welder.”
Performing hyperbaric welding trials within a controlled environment is essential to ensure safety and efficiency during mobilisation, and to reduce downtime offshore which could be time consuming and costly for the client, the spokesman said.