Cheriton Interchange Bridges have two span reinforced concrete bridge decks on reinforced concrete cantilever abutments and centre piers. The bridges were designed for HA and 37.5 units of HB loading to BE 5/73 & BS 153:Part 3A:1972. Reinforced concrete was designed in accordance with CP114 and BE 1/73(1st Revision). In 1978 the Central Electricity Generating Board requested that the west bridge be strengthened to carry a 450 tonne vehicle on 14 axles or 425 tonne vehicle on 12 axles. This modification was incorporated into the design before the Bridge was built.