Recollections and reflections on the construction of Scammonden dam (1966–1970)

Scammonden dam has been described as a unique structure, with its large embankment not only forming part of the M62 motorway, but also impounding a reservoir. This paper presents the recollections and reflections on this huge project from the viewpoint of its two authors, who were present on the site for most of the construction period. One of the authors, who is a highway engineer, was the materials engineer for the main contractor, Sir Alfred McAlpine & Son. The other author, who is a geotechnical engineer, was involved with some of the instrumentation. The important role of the contractor in sourcing materials for the embankment is described. Each author made a significant contribution in a sequence of events which arose towards the end of embankment construction. This began with identifying an issue relating to the extremely high pore-water pressures in the clay core and then in a preliminary assessment of the effect of this on upstream slope stability during the early stages of reservoir impounding.