It was in the last years of his life that Maunsell designed a series of bridges that place him joint top of my list of the innovators this century. He was nearly 70 when he decided to set up his own practice in 1955 with a young team of civil engineers that followed him when he dissolved the partnership of Maunsell, Posford & Pavry
Starting from scratch, within five years he had established his new practice as one of the best in the world in prestressed concrete bridge design. He travelled widely while in his 70s, trying to find work for his fledgling team and landed on his feet when he successfully bid for the design work of several major bridge crossings in Australia.
The multi-span concrete Narrows Bridge built in Perth, Australia, in 1957 was followed by the Tasman Bridge, in Hobart in 1958. Then came the precast prestressed segmentally constructed arch for the Gladesville Bridge which he conceptually designed and schemed. He sketched all the construction stages and the outline design of the structure on several sheets of tracing paper, but sadly never lived to see it built.
Back at home his first bridge commission was the Hammersmith flyover in 1958 - it was the first in the UK to use precast segmental, post-tensioned construction. The large savings in cost made by this construction method over more conventional designs in steel and reinforced concrete prompted the London County Council to make an exceptional ex-gratia payment to Maunsell for additional design fees.
Maunsell was an engineering polymath. While at Maunsell, Posford & Pavry he designed harbours, drydocks and dams around the world. He also designed the Falls of Clyde hydroelectric scheme in 1926, patented the Gambi pile and was the first to put forward proposals for an immersed tube construction in 1955.
Maunsell was also chief engineer for the 3,200m-long Stormstrund crossing in Denmark; and site agent on Putney Bridge widening. During the Second World War he was the designer of the Mulberry Harbour caissons, having previously designed several concrete boats and floating docks that were used during the First World War. He was a gifted painter whose drawings and water colours of civil engineering works are highly sought after today.