A rail tunnel formed within the flood barrier impoundments links the eastern limbs of Crossrail to complete a twin-track rail orbital of the Lower Thames Estuary from Central London. The estuary rail orbital with a 4sq.km floating solar array, cycle superhighway and promenade, including wayleaves for data storage, distribution and utilities, provides sustainable connectivity for over a million households, generating green-growth across the Lower Thames Estuary into Essex and Kent. Just 12km of new railway line creates a 132km Crossrail orbital of the Thames Estuary from Central London.
Construction undertaken in the tideway makes use of concrete batching and casting facilities nearby on the Isle of Grain and Hoo Peninsula. Spoil from the tunnel excavations is reused locally for embankments and flood bunds so that the embodied energy of construction and environmental impacts are kept to a minimum. The impoundments protect the estuary from tidal squeeze, thereby saving over 800 hectares of intertidal habitat and avoiding the need for managed retreat on the Isle of Grain.