The wreck of a 16 metre colonial ship - the Clarence - in Victoria's Port Phillip Bay has been transformed into a buried ‘time capsule' under the sea.
The wreck will be monitored by conservation scientists and maritime archaeologists every six months for the next three years as part of an Australian Research Council Linkage Grant.
The Clarence sank in five metres of water and was declared a protected zone in 1985, prohibiting access by divers and anglers. The site remained popular with local anglers whose anchors and fishing equipment had been damaging the site for decades. In February this year, Clarence became the focus of the Australian Historic Shipwreck Preservation Project.
Constructed of native timbers in New South Wales in 1841, Clarence is one of the best examples of small early colonial-built vessels, according to The University of Western Australia's Professor Peter Veth, leading archaeologist and Chief Investigator on the conservation and reburial of the wreck.
On 2 September 1850, Clarence ran aground on a sand bank in Port Philip Bay while transporting 132 sheep from Melbourne to Hobart. It had anchored in Coles Channel for the night, when the cable broke after a southwest to south southwest wind blew up. The sheep on board were rescued by Geelong residents, who would later enter into a dispute with the ship's owners. The result of the dispute is unknown. The loss of the vessel and cargo was estimated at £500.
The project is a collaboration between UWA, Monash and Australian National Universities, and 10 industry partners, including the WA Museum and the Victorian Department of Planning and Community Development. Its aim is to find out how effective the reburial intervention is for preservation of the wreck over time.
Thanks to the Clarence having a ballast of pipe clay, rather than the usual rocks and stones, some portions of the wreck and the artefacts buried by the clay - including leather patches for valves of pumps, lengths of rope and the bases and staves of oak barrels - have remained well-preserved in the oxygen-free environment it provided. However, other parts of the wreck have been destroyed by anchor damage, loss of seagrass and scouring. This appears to have become critical in the last 25 years.
Unlike renowned historically significant wrecks such as the Batavia which sank off the Abrolhos Islands in 1629 and the Mary Rose, which sank off the English coast in 1545 which were recovered in full, the Clarence and its artefact assemblages were studied both in situ and in laboratories located on a jack-up barge over the site.
The vessel and artefacts have been reburied and stabilised where it sank and its artefacts labelled and reburied both on and off the site in more stable and controlled conditions. The wreck will be covered by a significant sediment bed; shade cloth and geo-textile and finally robust PVC sheeting that will protect it from future anchor damage. This is the first time this technique has been used in the southern hemisphere.
"There are about 7,900 shipwrecks around the Australian coastline," Professor Veth said. "The in situ preservation and reburial program occurring on the Clarence provides a sustainable, cost-effective and strategic intervention to preserving both the structures and their assemblages which are clearly at risk."