Dessication and Destruction: The Immediate Effects of De‐watering at Etton, Cambridgeshire

Summary This paper presents the first results of a long‐term project to monitor changes in ground water conditions in parts of the East Anglian Fenland. So far the project has been concerned with two sites immediately north of Peterborough, at Borough Fen and Etton. The Borough Fen data are still being assessed, but Etton has provided results which warrant prompt publication. The water levels were monitored in a series of boreholes across the Etton Neolithic enclosure for a period of two years (1982–4), to study the effects of the variation in the local groundwater table on the waterlogged contents of the enclosure ditch. The first part of the paper (CF) assesses the results of this programme. The ambient water table remained at or above the level of the primary and lower secondary deposits in the ditch, thus accounting for the excellent preservation of botanical remains. Within one month of the adjacent quarry pumps being turned on the water table had fallen by up to one metre below the lowest archaeological deposits, and has not recovered since, to the almost immediate detriment of the botanical record. The second part of the paper (MT) discusses the observed variation in the preservation of wood in particular, and describes the effects of de‐watering on the deposits of wood in the enclosure ditch.