Our earthworks and infrastructure division reached another significant milestone last week, with the removal of the two billionth litre of water from the Western Cross Lake within the Eastern Quarry Development.
The Western Cross Lake, which is situated central to the Quarry, spans approximately 31 hectares in footprint, with a depth of almost 13 meters. Constrained by the presence of a Groundwater Source Protection Zone in the North-West, South-West and South-East of the Quarry, meticulous dewatering strategies have been implemented for long-term dewatering of the lake – which is designated as a major aquifer. To-date a number of dewatering techniques have been deployed to control both surface and ground water to ensure the constant maintenance of water quality. Such techniques have included; over pumping, installation of strategic pumping stations and formation of various cut-off ditches.
Situated to the North-East of the Western Cross Lake is the primary pumping station which is equipped with a fully encapsulated super silenced pump with an output capacity of 200 litres per second. The route covers over 2.2 kilometres in linear length and travels through Craylands Gorge, Craylands Pit, before discharging to Swanscombe Marshes and the Thames Estuary thereafter.
Declan Cogley, Erith’s Earthworks and Infrastructure Operations Director commented; “The dewatering of Western Cross Lake is integral to the delivery of the Ebbsfleet Garden City development. This volume accentuates the magnitude of this development and scale of what is being achieved by our team.”