Tuesday 19th September 2017 ‘Working on the Construction of Britain’s Motorways 1960-
1990’
Frank Duggan RCEA
The foundations of British roads were created in the Roman era. For the next 1500 years coastal shipping, canals and railways were used to transport people and goods. Subsequently, the first road built to Motorway standards in Britain was the Preston-by- Pass, completed in 1958.
From 1958 to 1990, 2000 miles of Motorways were constructed. This compares to the 2000 miles of roads built by the Romans, and the 14,590 miles of Railways built during the years 1825 and 1852.
The demolition and re-construction the new London Bridge (1968-1972) over the Thames was one of the first major bridges built in the 20th century Motorway era.
In the 1960’s temporary re-erectable flyovers were thought to be the solution to traffic congestion. These were designed to solve bottlenecks at cross roads and were erected in Bristol, and on the M40 in West London. Planners expected them to have a number of re-uses. Instead they became an indispensable part of the road system and remained in place for around 30 years.
Computers programmes were developed in the 1960’s. They had an immediate effect, and facilitated the development of procedures that revolutionised the design of road alignments.
The construction of Brent Cross Flyover (1966- 1968) over the North Circular Road in North London was also an early structure.
This was built to remove a bottleneck on the North to South, and East to West, flow of traffic, into and out of London.
The contract was hit by tragedy as shown opposite. In 1964 the jib of a mobile crane erecting a derrick collapsed onto a moving coach. 7 died and many more were injured.
In the early 1970’s it became Government policy to move businesses from City Centres, ease congestion in tourist areas and improve infrastructure between cities in the South East. These plans involved the construction of the A30 Exeter bypass, the M11 London to Cambridge Motorway and the A470 Cardiff to Merthyr Road shown opposite.
By 1982 most of the M25 had been completed, and the final sections got underway. Completion made the M25 for a time the longest City bypass in the world. The M25/M40 interchange shown opposite was completed in 1985. This contract employed the first reinforced earth retaining wall, and, by designing the M25 to pass through one of the arches of the Chalfont Railway viaduct which had been built around a century earlier showed how engineers could collaborate over the centuries.
The Chapel-en-le- Firth bypass in the Peak District was one of the most difficult road contracts undertaken in the UK. Cost escalated from £18m at tender, to £45m on completion. The extra cost was due to difficult geological conditions, and in overcoming engineering problems brought about from building through extensive fill deposits. These had been laid down when the area was a centre of lime and quarrying activities.
Today we are in a period of ‘Smart Motorways’. Technology is being used to reduce congestion, improve journey times, and make a more comfortable driving experience. The M42 shown opposite is a good example.
New infrastructure has also benefited from the advance of technology. The recently opened Queensferry cable-stayed bridge has 2000 sensors embedded into the structure and these produce 8Gb of data daily.
Roads are now being successfully used to provide energy from photovoltaic tiles built in to the surface. In France the energy this provides is being supplied to the national grid. In Alberta, Canada this technique is also being employed.
The Highways Agency in Britain is considering covering motorways with cantilever canopies to reduce pollution, and building double decker roads as a means of reducing the environmental impact on land and to increase road capacity.
The future use of our roads will be dictated by the rapid developments in technology. Mass production of vehicles and the building of motorways provided work for thousands, and the wide availability of road transport and motorways provided undreamed mobility for millions.