Contract Archaeology

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Photo by Maggie Cox

The 1990s also saw work undertaken by contract archaeological units (such as Museum of London Archaeology, Pre-Construct Archaeology, Oxford Archaeology and AOC Archaeology ) which related to developments affecting the foreshore through the construction of new bridges, river walls, mooring pontoons and other infrastructure.

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Greenwich Wharf
Photo by Andy Chopping

These projects included site investigations and foreshore surveys at Walbrook Wharf, Jubilee Gardens, Blackwall Stairs, County Hall, Deptford Creek, Woolwich Arsenal, Tower of London, Bankside, Tower Pier, Millennium Bridge (image at top of page), Millbank, Barnes, Wandsworth, Chelsea, Vauxhall Bermondsey and Greenwich Wharf (right).

The Role of the Mudlarker

These commercial investigations, while often restricted to a specific area (for example, the limit of the ‘site area’ is usually defined by the area of impact of the proposed development, rather than specific research aims), are nonetheless of vital importance to the on-going study of the archaeology of the Thames. These projects demonstrate the importance of revisiting and monitoring of foreshore areas; due to the erosive nature of the tidal environment, new archaeological features and artefacts are consistently being recorded. The site at Chelsea provides a useful example; a number of surveys from 2001 to 2006 by Museum of London Archaeology have recorded additional human skeletal material (the remains of three individuals are now represented) and a second mid-Saxon fish trap. In this context, the important role of the Society of Thames Mudlarks and the Thames and Field Metal Detecting Society (who are licensed by the Port of London Authority to search for foreshore artefacts) is also highlighted; for example during 2001, a mudlarker reported the discovery of human bones at Bermondsey, which were dated to the early post-medieval period. The recent discoveries on the Isle of Dogs were made under similar circumstances.

Erosion Studies

The dynamic riverine environment is constantly excavating new material for us, which means the active disintegration of archaeological features which are already exposed. This has been dramatically confirmed on a number of sites, and an exercise in measuring the rate of decay of a specific archaeological feature was undertaken in Chiswick. In 2006, the post-medieval causeway leading from the river to the church was recorded in detail prior to a proposed refurbishment of the structure.

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Scale drawing of Chiswick Causeway

The causeway had previously been studied by the Thames Archaeological Survey during 1996, while an additional photographic record had been created during a reconnaissance visit by the Museum of London Archaeology Service in 2003. A comparison of the archive material with the surviving remains on the site showed that the structure had undergone marked deterioration over the ten year period, while examination of the make up of the causeway demonstrated successive phases of historic and modern repair.

Survey

The involvement of commercial units on foreshore sites and the rapid developments in digital technology has meant an increased use of advanced surveying techniques.

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MoLA surveyor using GPS on the foreshore, photo by Maggie Cox

The use of equipment such as Total Stations, reflectorless electronic distance measuring machines (rEDM) and Global Positioning Systems (GPS), allows an extremely accurate digital record to be created swiftly on site. With short tidal windows severely restricting time on site, and the lack of Ordnance Survey bench marks on the foreshore, digital survey equipment has proved to be an extremely efficient tool. This technology was also used by Wessex Archaeology during survey along the north Kent shoreline of the Thames Estuary shoreline of the Thames Estuary.