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, and the other author, who is a Geotechnical Engineer, was much 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.