Cellarhead Atlantic Green Connection is a user connection to an existing NG substation. Omnia Projects were contracted to extend the double busbar arrangement as part of the NG infrastructure works on behalf of National Grid.
Owing to the main and reserve busbar extension, the fence line for the site required extension. The design for the fence line extension and subsequent earth works also formed part of the Omnia design.
The earthworks required for the substation extension were significant. The existing substation ended at the bottom of a large hill slope, which required levelling off to accommodate the new bay. The existing ground was made up of a shallow layer of hard sandstone rock. This posed a significant restriction which resulted in the minimisation of the bay extension design to reduce its footprint as much as possible.
The civil design scope included the production of site elevations, illustrating the new substation levels in order to support the planning application for the bay extension and reduce the impact of heavy construction traffic.
Omnia’s civil design package also allowed for the consideration of future additional bays.