Scope of Work
Categories:
Submarine Cable InstallationVessel Services
Lifecycle Stages:
Construction
Quantities:3.5 km submarine cable (export)
Cable Specifications:
TypeHVAC
Purposeexport
Voltage220 kV
Route Length76 km
Source text:
Jet trenching and burial of approximately 3.5 km of 220 kV HVAC Walney Extension export cables (Walney 3 and 4 East/West) on the offshore route between the Walney Extension substations and the Heysham landfall.
Contract Details
Award Date:22 Apr 2020
Client:
Ørsted
Description
Rotech Subsea carried out a post‑lay cable burial project on sections of the Walney Extension export cables, which form part of the Walney Extension OFTO transmission assets. Working for Ørsted, Rotech acted as the marine contractor, chartering the OSV Relume and engaging the required subcontractors. Using its TRS1LD jet trenching tool, Rotech trenched two separate 220 kV HVAC export cables associated with Walney 3 and 4 (Walney Extension East and West), totalling approximately 3.5 km. The cables were buried to target depths of around 2.0 m in soft sand and 1.0 m in stiff clay along the Irish Sea route to ensure adequate protection and compliance with burial specifications. This scope enhanced the protection and integrity of the OFTO export cable system after initial installation.