Thames East Bridge
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.