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NETWORK / 30 / DECEmbER 2016/jaNuaRy 2017 u 3km cable laid 80m under England's deepest lake u 6,000 hours worked u 24 joiners, fitters and linespeople worked on the project u Six studies were carried out u Two Sites of Special Scientific interest u £584k project spend Innovation in cable maintenance and replacement generally revolves around developing no- dig technologies and speeding up the process to cut the inconvenience of streetworks. but sometimes a replacement scenario is so unique it only occurs once every 40 years and requires a completely different approach – and a link-up between new areas of the energy industry. Electricity North West (ENW) found itself in such a scenario when the 3km cable running underneath England's deepest lake was due for upgrade this year. The challenge saw it partnered with a subsea cable specialist to overcome its watery installation problem. The cable running underneath Wastwater – a 5km-long, 0.8km-wide and 80m-deep lake in the Lake District – was originally installed in 1977 when Wasdale Head was first connected to the electricity network by ENW's predecessor Norweb. as well as being the deepest of the lakes, Wastwater is surrounded by mountains Red Pike, Kirk Fell, Great Gable and Scafell Pike – England's highest mountain. but the challenges surrounding the replacement of this cable were not just topographical. Extending the length of the southeast side of the lake are the Screes, consisting of millions of fragments of broken rock and rising from the floor of the lake to a height of over 600m. martin Deehan, operations director for Electricity North West, explains: "This was an incredibly difficult job due to the extremely remote location and sensitive area. The lake itself is a designated Site of Special Scientific Interest as is a large area of the scree slopes alongside." Great care was therefore taken throughout the £584,000 project to ensure all work was carried out to ensure the approval of the satisfaction of various agencies and trusts – such as Natural England, the National Trust and the Environment agency. ENW worked with cable contractors Gallaghers and subcontracted Dutch subsea cable installation specialist VbmS to develop a bespoke submarine cable for the project. This cable was then manufactured by its cable- manufacturing partner Prysmian. The cable was delivered to site and offloaded by a crane onto 1,400-1,600m specialist trailer drums weighing between 16,750 and 18,900kg. The cable was then floated down the lake until it was in position before being carefully lowered to rest on the lake bed. This installation phase took a couple of days to complete with minimum disruption to residents. The essential work undertaken by ENW has ensured residents and businesses will continue to receive the essential power they need for the foreseeable future. Use case electricity North West aNd WastWater

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