Diversion of the River Calder at Welbeck: An Engineering and Environmental Challenge

The Welbeck reclamation and landfill project (near Wakefield) is reclaiming over 1.5 km² of former aggregate and colliery workings through the creation of a new landform. This is to incorporate millions of tonnes of colliery spoil and controlled (i.e. household, trade) wastes, and to avoid the need for disposal on less suitable sites elsewhere.
The scheme is already under way, but the proposed diversion of the River Calder to one side of the site would more than double its capacity for landfill. In environmental terms, the project has been seen as the creation of a new river corridor, rather than simply the diversion of a river channel.
The paper outlines the engineering of the river diversion, which is routed for about 2 km through varied and difficult ground conditions, and gives a number of examples of the priority attached to landscape and after-use factors, and their intrinsic importance in design.