Phase Site Investigations were recently involved in an archaeological geophysical survey along the route of a proposed new water pipeline in the south of England.
Several archaeological sites were known adjacent to the proposed route so the consultant on the project specified that the entire route (51h a) should be covered by a magnetic gradiometer survey. The aim of the survey was to assess if any of these sites extended into the pipeline corridor and to determine if there were any additional archaeological remains present.
Our surveying experience helped us greatly as we were able to rapidly establish survey grids along the entire route using an RTK GPS system. The survey grids were directly related to Ordnance Survey grid co-ordinates allowing straightforward and accurate magnetic data collection and interpretation.
The survey identified areas of medieval ridge and furrow ploughing, numerous areas of potential archaeology, including several previously unknown archaeological sites, and also the routes of several existing water and gas pipes.
The results of the survey meant that the amount of archaeological excavation required to record the sites could be accurately quantified. In one instance the route could be revised to avoid a major archaeological settlement that would have been very expensive to excavate, thus effectively saving the client money. A secondary benefit was that the survey had accurately located existing pipelines and so a safe easement between these and the proposed new pipeline could be allowed.