The wreck of HMS Colossus lies to the south of Samson Island in the Isles of Scilly. There are two main areas of wreckage, lying 750m apart. Part of the wreck is designated under the Protection of Wrecks Act 1973. The Stabilisation Trial is being undertaken within the current protected area.

Although the fabric of the vessel is remarkably well preserved, sand reduction across the site is causing the exposure of timbers and artifacts. The reasons for the loss of sand are unclear but once exposed on the seabed, deterioration of the timbers is fairly rapid.

In order to achieve a conservation and management plan for HMS Colossus, English Heritage commissioned an assessment of the site in January 2003. This work investigated the 'archaeological history' of the wreck and noted that the site is under threat from 'continued lowering of the sand levels'. The assessment recommended that the patterns of sediment movement and sand levels be monitored.

In order to fully assess the marine environmental conditions surrounding the wreck, the Stabilisation Trial was commissioned in March 2003. It is anticipated that this study will contribute to the preservation of other sites Designated under the Protection of Wrecks Act

A series of underwater investigations commenced in March 2003 which included the installation of experimental protective matting and the measurement of sediment levels. Monitoring is due to be completed in 2005 and it is hoped that the results will be published in the International Journal of Nautical Archaeology.