The works were being undertaken by the Electricity Alliance West, a partnership between National Grid, Babcock, AMEC and Mott McDonald. Prysmian Cables were contracted to supply and install the new cables and Neary Construction were appointed as the civil sub-contractor with Hewson Consulting Engineers as their designer.

The original 2 x 400kV oil filled circuits were being replaced by new XLPE cables as they had reached the end of their useful life span. The detailed scope required the installation of two replacement circuits between Cable Sealing End compounds over a total distance of approximately 3.5km. It also included the refurbishment and re-construction of the two CSE Compounds.

We designed temporary trench support systems for the 3.5km installation of the 400 kV cables. Two designs were carried out, one for atypical trench and one for the wider and deeper joint bay. In addition we designed a new retaining wall, a bunded compound and various other miscellaneous permanent structures.