Science and Heritage Programme

In situ preservation of wetland heritage: hydrological and chemical change in the burial environment of the Somerset Levels, UK

University of Reading/ English Heritage

Award holder - Professor Martin Bell
Student - Louise Jones


A 3 year PhD project in partnership between Reading University, English Heritage and Somerset County Council will monitor in detail the effects of seasonal water-table and chemical changes to two internationally important prehistoric wetland sites in the Somerset Levels. This will contribute to the development of more effective strategies for in situ preservation of heritage resources.


To enhance our understanding of the effects of water-table changes on wetland archaeological sites where organic artefacts (eg wood) are preserved. Chemical changes occur when water-tables fluctuate and as a result of floodwaters derived from agricultural land. To preserve sites in situ we need a better understanding of the changes occurring and their effect on the burial environment.


  • To what extent do seasonal water-table fluctuations occur on the study sites? What are the effects of these on soil chemistry and the preservation environment of organic and other artefacts?
  • What are the effects of floodwater derived from agricultural land on the soil burial environment?
  • Can models be developed to predict preservation levels and inform strategies of in situ preservation in a context of climate and land use change?


Monitoring boreholes will be established at the study sites: Glastonbury Lake Village and the Sweet Track. Water tables and chemistry will be monitored over 17 months. Elemental composition of the soil solution, pH and Redox will be monitored.


The extent and chemical effects of water-table changes on the study sites will be established. Detailed monitoring of these sites will inform strategies of wetland conservation and management more widely.


In July 2007 the leading nature conservation organisations, the Environment Agency and English Heritage launched the '50 year vision for Wetlands'. In order to enhance biodiversity and sustainability extensive new wetland reserves are proposed. This research contributes to the development of effective strategies of combined wetland heritage and nature conservation. Research will also inform Somerset County Councils plans to propose a Somerset Levels World Heritage Site.


University of Reading:  Professor Martin Bell, Dr Matthew Almond, Dr Steve Robinson;  English Heritage: Dr Sebastian Payne


Louise Jones

Louise Jones started her PhD project in 2008 after completing an MSc in Geoarchaeology, and a BSc in Environmental Geology, both at the University of Reading.  As this is an interdisciplinary project she has three supervisors, and somewhat uniquely, is based in three departments in the University: Geography and Environmental Science, Archaeology and Chemistry.

Louise is investigating the topic of in situ preservation, which is a core strategy for the conservation and management of waterlogged remains at wetland sites.  Inorganic and organic remains at wetland sites can quickly become degraded, or lost entirely from the archaeological record, as a result of chemical or hydrological changes within the burial environment, so monitoring these parameters is crucial in identifying baseline data for a site, the extent of spatial and or temporal variability in these parameters, and to evaluate the potential impacts of these variables on current and future in situ preservation potential. 

Since August 2009, monthly monitoring has taken place at two internationally important sites in the Somerset Levels - the Iron Age site of Glastonbury Lake Village, and the nearby southern section of the Neolithic Sweet Track bordering the Shapwick Burtle. The core research objectives are to identify whether a spatial, stratigraphic and analytical approach to the analysis of sediment horizons, and monitoring of groundwater chemistry, redox potential, and water table depth, can be used to characterise the burial environment at these two sites more fully, and therefore inform on current and future in situ preservation potential.  Central to this strategy is the identification of the extent of spatial and temporal variability within these parameters.  This monitoring data is already identifying spatial and temporal variability in some of these parameters and continued analysis will further highlight the possible impacts on in situ preservation potential.  

Image: Measuring the water table depth at the Sweet Track site. Photograph by Prof. Martin Bell, University of Reading, 2009)


Recording and sub-sampling a sediment core taken at the Sweet Track site. (Photograph by Martin Bell 2009)

Recording and sub-sampling a sediment core taken at the Sweet Track site. (Photograph by Martin Bell, University of Reading, 2009)