Thameslink 2000 needs extra track width if it is to succeed. The largest bottlenecks are around Borough Market near London Bridge and at Blackfriars. With architect Tony Meadows, aha is designing a new viaduct at Borough. It spans 75m across Borough Road near London Bridge with a sensuously curved steel truss, allowing more sensitive placing of structural supports in the historic market below.
More ambitious is the Blackfriars station redevelopment with Will Alsop. Relocating the station on to the bridge across the river makes either bank equally accessible. The initial structural solution re-used the existing supports at 60m centres (with an overall length of about 240m). Torpedo- shaped trusses spanned across the tracks with drooping belly trusses spanning the 60m between them. This kept an absolutely minimal roof zone above the 5m clearance which trains need, to reduce the effect on St Paul's views. Later schemes, including a mast and cable-stay scheme, are perhaps more obtrusive.