UK-headquartered heavy transport specialists Collett & Sons successfully delivered two 160-tonne inlet valves to the Dinorwig hydropower station as part of an essential upgrade scheme.

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Working on behalf of Rhenus Project Logistics, Collett has completed the first two deliveries of the upgrade project, which aims to extend the power station’s operational lifespan for the decades ahead. A total of six valves will be delivered to complete the project, each measuring 5.3 m x 4.7 m x 3.7 m.

Prior to deliveries, meticulous preliminary works were completed by Collett’s project management and consulting departments. This included swept path analysis (SPA) reports, lashing calculations and plans, stability calculations, as well as a comprehensive test run and route studies. During the test run, a load replicating the exact size and shape of the valves was constructed to ensure safe transportation.

The first two inlet valves arrived at the port of Penrhyn, located East of Bangor, North Wales. Working under CPA Contract Lift conditions, Collett discharged both valves from the vessel using an 800-tonne lift capacity mobile crane. Ensuring secure transport, each valve was carefully lashed onto two 10-axle modular trailers. The journey from port to power station spanned approximately 12 miles (19.3 km), with a travelling time of 3 hours. Throughout the transport, a support system was in place, including full police escorts and Collett’s own escort vehicles. The loaded trailers were accompanied by three 8 x 4 ballasted tractor units, two primary and one in support. Special Order BE16 permits were obtained to facilitate the move.

Upon arrival at the power station, the two main inlet valves were directly transported to a designated storage area and lowered onto stools. After later preparation, the valves were transported into the mountain and offloaded by overhead gantry cranes.

The Dinorwig hydropower plant, located near Llanberis in the Snowdonia National Park, is the largest pumped hydroelectric storage facility in the UK. With a maximum power supply of 1,728 MW and a storage capacity of approximately 10GWh, the station efficiently manages water between the Marchlyn Mawr reservoir and the Llyn Peris Lake to generate power as needed.