TfL | London Bridge to Dartford Crossing, London 2015
Addressing the famous lack of river crossings in East London this proposal is for a series of bridges spanning the Thames between London Bridge and the Dartford Crossing. Where the Thames Gateway Bridge would have created a single high capacity and high clearance fixed connection across the river - addressing the strategic need for a link - this proposal instead posits that a number of smaller opening crossings could be formed, joining roads north and south in a more opportunistic manner and at a similar frequency to that found in Central London.
In order to maintain access for shipping a series of swing bridges are proposed where the channel width has been determined by the existing constraint at the Thames Barrier. The opening main span would be cable stayed, with a counterweight situated where the pylons meet, well behind the pivot line. The structure would therefore be balanced such that the centre of gravity in the free [open] position was located on the same vertical axis as the rotational bearing.
The approach spans would be simple viaducts, the vertical clearance of which would be established to provide enough air draft at Mean High Water for barges, leisure and tourist vessels to pass unimpeded. Alternatively it would be possible for some crossings to have multiple opening spans connected by viaduct – to facilitate separate east/west shipping channels where the river is widest and water traffic greatest.