Building record 6948/1/2 - M1 Motorway Bridge (Maple Farm Access Road Bridge)

Maple Farm access bridge is a motorway bridge for farm vehicles and pedestrians designed by Sir Evan Owen Williams and built in 1958/59 during the first phase of construction of the M1. The bridge is made of cast in-situ reinforced concrete. The sides are formed of concrete panels with faceted horizontal bands. An external cornice at the base of the sides follows the line of the bridge to each end. Central support is provided by a heavy, circular column under a splayed and square head, which stands on an elongated ovular-shaped plinth. End support is provided by heavy circular columns on square concrete pads.

{2} Maple Farm access bridge is a motorway bridge for farm vehicles and pedestrians designed by Sir Evan Owen Williams and built in 1958/59 during the first phase of construction of the M1. The bridge is made of cast in-situ reinforced concrete.

{3} CONTEXT
English Heritage has been asked to assess two M1 motorway bridges for listing in the light of proposed widening of the carriageways.

A report by Carillion-URS on behalf of the Highways Agency, 'M1/M45 Original Sir Owen Williams Parapets for English Heritage Proposal: Feasibility for Upgrading in Concrete', has been taken into account. This report examines the potential for retaining the original appearance of the bridges over the relevant section of the M1 and M45. It is this report that has led English Heritage to assess the Maple Farm bridge, in question here, for Listing, and another bridge which is dealt with separately (UID: 163633). The report highlights greater difficulty with safely maintaining the M1 bridge parapets than the parapets of bridges over the M45. It recommends that the viability of retaining a concrete parapet for the Maple Farm bridge for heritage purposes should be examined by the Highways Agency.

HISTORY
The majority of bridges built during the second half of the C20 were either concrete or steel. The most significant changes in technology post WWll were the arrival of the use of pre-stressed concrete and welding or grip bolts, replacing riveting, from mainland Europe. Improved materials, understanding of ground conditions, improved joints and bearings, and development of older technology brought greater economies to bridge building. During WWll very little bridge building happened in Britain, although unused WWll, stockpiled, pre-stressed concrete bridging beams were pressed into service after the War in urgent cases. Even so, it was not until the late 1950s that a demand for new bridges grew with the gradual improvement in the nation's economy.

In spite of the emergency use of pre-stressed concrete, the first pre-stressed concrete bridge of a large scale was not erected in Britain until 1954 when the Northam Bridge, over the River Itcham at Southampton was replaced. Before the end of the 1960s, pre-stressed had superceded reinforced concrete for all but the smallest bridges.

Sir Evan Owen Williams (1890 - 1969), architect and engineer, is arguably Britain's most significant innovator in the early use of structural concrete. He began his career as Assistant Engineer at the Indented Bar and Concrete Engineering Company in 1911, became Senior Designer and then Chief Estimating Engineer for the Trussed Concrete Steel Company from 1912 until 1916, before launching his own company, Williams Concrete Structures Ltd., in 1919. His designs are wide ranging and include buildings, bridges, boats and even aircraft. His early bridges were most often designed with the architect Maxwell Ayrton, and include notable works: the very striking Findhorn Bridge (1926), at Tomatin and the faceted Crubenmore Modern Bridge (1926) near Newtonmore, both in Scotland; also the Wansford Bridge, Wansford (1928) and the Lea Valley Viaduct, North London, (1925 but now demolished), are just a few examples. In some circles Williams is perhaps most famous as the designer (again with Ayrton) of Wembley Stadium (1923) and he also worked on the British empire Exhibition buildings (1924), the Daily Express buildings in London and Manchester ( 1931, 1939), the stunning D10 and D6 Boots factory buildings in Beeston and Nottingham (1932 and 1938), and the BOAC Maintenance Headquarters at Heathrow (1955), amongst many others. The later years of his life from 1955 onward, were devoted to the development of the M1 motorway in two phases. Phase 1 (work started in 1958) included some 130 overbridges and underbridges.

British motorways were contemplated before 1939, but action was prevented by the Second World War. The Special Roads Act of 1949 allowed motorways to be built but again delays were forced by the weak post-war economy and so construction did not begin until the 1950s. The first to open were the Preston by-pass, now a section of the M6 (essentially a pilot project), which opened in 1958 and the M1, Britain's first full length motorway, in November 1959.

The first phase constructed of the M1 runs between Pepperstock, near Luton, and Crick. Maple Farm bridge was therefore constructed as part of this phase in 1958/9.

DESCRIPTION
A motorway bridge for farm vehicles and pedestrians made of cast in-situ reinforced concrete. The sides are formed of concrete panels with faceted horizontal bands. An external cornice at the base of the sides follows the line of the bridge to each end. Central support is provided by a heavy, circular column under a splayed and square head, which stands on an elongated ovular-shaped plinth. End support is provided by heavy circular columns on square concrete pads. Some metalwork is exposed where the concrete has broken away from the surface and there is some patching, but otherwise the bridge is intact.

ASSESSMENT
For buildings erected after 1840 progressively greater selection is necessary when assessment is made for listing. Interest in bridges may lie in several areas, the aesthetics of its design, the materials technology, the engineering technology (i.e. how it achieves the span and carries its load; perhaps its method of construction, if, for example, it was self supporting during construction) as well as the significance of the engineer or the architect.

Maple Farm access bridge appears to be intact but when set along side post-war bridges that have been listed, at least in part, for their architectural quality, the bridge is heavy, lacking the elegance and lightness of the listed examples. These copmprise the Wentworth Viaduct over the A1 near Wakefield; the Swanscombe Footbridge over the A2 near Dartford; and the Winthorpe Bridge over the A1 near Newark.

Pevsner was not impressed by the quality of the M1 bridge architecture, which he notes 'impress by a cyclopean rudeness'. The design of all the M1 bridges are variations from the same basic template and Maple Farm bridge is in the mould Pevsner describes, nor does it have the impressive weight and mass of the road bridges. In the context of a motorway, assessment for designation may find less interest in a farm access bridge where the bridge has been put forward as a sample and has not selected itself, as it were, by virtue of its intrinsic quality.

The interest in the bridge does not lie in its architectural design but rather in its designer, Owen Williams, and in the fact that it spans Britain's first full length motorway. Williams was renowned for his desire to merge the engineering and architecture disciplines and in many ways this ambition is embodied in his M1 bridge designs, which have some architectural flair but which at the same time are clearly exercises in engineering, as Pevsner found.

18 structures of Owen Williams' are on the List already, including the Daily Express buildings in Grade ll* and the Boots factories in Grade 1. His mass concrete bridge carrying the Great North Road over the River Nene at Sibson Cum Stibbington, is listed in ll*.

Nevertheless, it is clear that the bridge in question here fails to reach the quality of design of other works of Williams. This is a simple and plain bridge. It is made of reinforced concrete, cast in-situ using a technology that was soon to be old fashioned in England, and already was on the Continent where pre-stressed concrete was tried and tested for bridges before the Second World War. It is likely that Williams felt that pre-stressed concrete was untested in Britain but this, nevertheless, lessens the interest in Maple Farm Bridge.

There are 29 road bridges on the List dating from after 1901, and nine bridges, including footbridges, dating from after 1939. The latter is a mixed bag dominated by concrete of which most have technological or architectural interest. An apparently modest footbridge of 1949 over the river Cherwell in Oxfordshire, for example, listed in Grade ll, has claims to be the first pre-stressed fixed-arch bridge in the world. Of the major road bridges listed, the Runcorn Widnes Bridge, as an example, was the third largest steel arch in the world, when built, and similarly the Wentbridge Viaduct (1961) also in Grade ll, was the largest of its kind in Europe and the first in England to use pre-cast concrete hinges and pre-stressed cables. It was also listed for the quality of its architecture. The bar, therefore, is set high when making a selection for listing.

Maple Farm bridge, therefore, whilst not being without merit, does not impress by virtue of design. Its interest lies in the fact that it was designed as part of Britain's first full length motorway by an eminent architect/engineer. Nevertheless it is not the best example of his work, is not up to the quality of bridges already on the List and was not innovative. It does not merit designation.

SOURCES
www.engineering-timelines.com/who/Williams_O/williamsOwen6.asp
Smyth W.J.R. 'UK Concrete Bridges Since 1940', in Proc. Instn. Civ. Engrs Structs & Bldgs, 1996, 116, Aug/Nov 432-448 (1)

<1> Smyth W.J.R., 1996, UK Concrete Bridges Since 1940, p.432-448 (unchecked) (Article). SNN108393.

<2> NATIONAL MONUMENTS RECORD, 2012, NMR Monument Report, HOB UID 1480174 (unchecked) (Database). SNN108196.

<3> ENGISH HERITAGE, English Heritage Listing File (Report). SNN111579.

Record last edited

Feb 5 2025 6:08PM