This notice provides an update on the current (October 2024) information that is available for mariners operating in the eastern Irish Sea in the vicinity of the Isle of Man Interconnector Cable. It includes a summary of information about the cable route, the location of rock mattresses, and locations where the cable may be exposed.
The Isle of Man Interconnector Cable
The Isle of Man Interconnector Cable runs beneath the sea between Douglas on the Isle of Man and Bispham on the Lancashire coast. It was installed in September 2000 and spans a distance of 104km (56 nautical miles), linking the Isle of Man to the UK National Grid near Bispham in Lancashire (see ilustrative map below).
IOM Interconnector Route
Information for Mariners
The most up to date information leaflet for mariners about the IOM Interconnector Cable can be downloaded here. The key features of the cable route that are of interest to mariners are summarised below.
Cable Protection
At several points along the cable route the cable is surface laid where there are joints between sections of the cable and where it crosses other cables and pipelines.
To protect the surface laid cable along the route, protective mattresses were installed at six locations. Details of these locations are given in maps that are shown in the leaflet that can be downloaded here.
Surveys in 2011 found that there had been some movement of the rock mattresses at KP57.3 on the cable (from 53° 57.24′ N 003° 40.80′ W to 53° 57.12′ N 3° 40.50′ W), which is approximately 30.5km (16.5nmi) west of the Lune Deep cardinal marker buoy . You can download a notice about the rock mattresses along the cable route and potential hazards in this area here.
Exposed Cable close to Lancashire coast
The seabed close to the Lancashire coast is very mobile. Parts of the cable lying within 2 nautical miles of the Lancashire coast may occasionally be exposed by movements of the sand on the seabed. The Manx Cable Company monitor the cable carefully along this part of the route, and have published a notice to mariners based on survey information that can be downloaded here.
Background information
More information about the IOM Interconnector cable can be found on our website here. The Manx Cable Company is part of Manx Utilities. More information about the Manx Cable Company can be found here.