Event/Activity EPM226 - An Archaeological Watching Brief on a Borehole Investigation at No. 2 Dock Portsmouth Historic Dockyard

An archaeological watching brief was undertaken by Pre-Construct Archaeology on the sinking of a geotechnical borehole in Portsmouth Historic Dockyard between 21st and 25th March 2011. The borehole was located on the western side of HMS Victory, 4.85m from the edge of Dock No. 2 (berth of HMS Victory). It was drilled to a depth of 25m using a 0.26m core bit. The main purpose of the borehole was to install monitoring equipment to record ground water pressure as affected by tidal flows and its effects by movement on Dry Dock No. 2 and HMS Victory. It was also drilled in order to establish the nature of below ground deposits in the immediate vicinity. The sinking of a second borehole on the eastern side of HMS Victory had originally been planned, but was abandoned due to time constraints. Scheduled Monument consent was obtained prior to the work taking place. The work was monitored by an archaeologist and a digital photographic record made. A small number of granite cobble sets were lifted to allow the drilling to take place, to be replaced once the work had been completed. No archaeological finds or features were encountered during the watching brief, but comprehensive data on the underlying ground strata was obtained. The latter gave an indication of the original profile of the shoreline prior to land reclamation which took place during the 17th and 18th centuries. The presence of a large modern concrete slab encountered below the cobble sett surface laid around HMS Victory suggested that the cobbles had been re-laid in recent times.