The document also discussed the various forms of bridge and tunnel solutions along with conceptual designs for a bridge solution on Route 6A.
ForthTAG has examined all of the routes shown on the above diagram and has discounted Routes 1A, 2, 3 and 4 as being too far west especially in the light of the recent contract award to build a bridge on Route 1B.
This new bridge will cater for traffic from the M90, via the Kinross junction, travelling west towards Glasgow and the M74. Routes 6B, 7, 8A and 8B were discounted as sites for a bridge due to their length and location. Route6A is close to the line of the bridge being proposed by FETA, the difference being that Route 6A proposed to use Beamer Rock as a Land fall in the centre of the river; this would have given a dual span bridge solution with spans of approximately 1.0km. FETA are now proposing a more expensive solution west of this location. The higher cost is mainly due to the increase in clear spanning the river with a proposed span of 1.4 km.
An Immersed Tube Tunnel solution, linking the M90 via a Rosyth Bypass to the M9, is the least environmentally damaging. This would cost a third of a new suspension bridge, and its location would enable the optimum traffic solution. If the abandoned Trident dry dock were to be used, a tunnel could be constructed three years earlier than a bridge.