Listed Building: Derwent Viaduct (SPC8 42) (1417625)

'Summary A five-span skew arched viaduct built in 1836-40 for the North Midland Railway to the designs of George and Robert Stephenson with Frederick Swanwick. Reasons for Designation Derwent Viaduct, built in 1836-40 for the North Midland Railway to the designs of George and Robert Stephenson with Frederick Swanwick, is listed at Grade II* for the following principal reasons: * Historic interest: the viaduct forms part of a series of railway structures built for the North Midland Railway between 1836 and 1840. The line was designed by George and Robert Stephenson, two of the most important and influential engineers of the railway era, aided by Frederick Swanwick, the company's resident engineer. It is considered to be one of the best preserved examples of the pioneering phase of railway development in England, and retains many of its original engineering structures; * Engineering interest: it is one of the few surviving stone viaducts on the line and exemplifies the architectural flair with which the Stephensons applied themselves to engineering challenges. Cutting-edge developments in skew arches were designed specifically to meet the requirements of the railway, enabling them to be built in large numbers for the first time. Skew bridges represent a truly innovative engineering solution of the pioneering phase of railway development. This outstanding structure was at the forefront of railway engineering in the world. * Architectural interest: the impressive aesthetic quality of Derwent Viaduct far exceeds its functional and structural requirements. It is a finely composed viaduct constructed of masonry that has been worked to the highest standard, and it demonstrates the consistently high quality design and careful detailing of the railway structures completed for the North Midland Railway; * Modification: the extension of two piers and an abutment to support a new track were carefully faced with coursed, quarry faced gritstone to minimise the impact of the intervention. This modification has not unduly detracted from the architectural integrity of the viaduct, and it reflects the evolution of the line which has played an important part in forming its character. History The Midland Main Line is the outcome of a number of historic construction phases undertaken by different railway companies. The first two phases were carried out simultaneously between 1836 and 1840 by the North Midland Railway and the Midland Counties Railway. The North Midland Railway, which operated between Derby and Chesterfield and onwards to Rotherham and Leeds, was pre-eminently the work of George (1781-1848) and Robert Stephenson (1803-1859) who, along with Isambard Kingdom Brunel, are the most renowned engineers of this pioneering phase of railway development. They worked closely with the Assistant Engineer, Frederick Swanwick (1810-1885). The railway’s architect Francis Thompson (1808-1895) designed stations and other railway buildings along the line. The less demanding route for the Midland Counties Railway, which ran between Derby and Nottingham to Leicester and on to Rugby, was surveyed by Charles Blacker Vignoles (1793-1875) who was engineer to a large number of railway projects. These two companies (along with the Birmingham & Derby Junction Railway) did not yield the expected profits, partly because of the fierce competition between them. This led to the three companies merging into the Midland Railway in 1844 which constituted the first large scale railway amalgamation. The next part of the line from Leicester to Bedford and on to Hitchin was constructed between 1853 and 1857 by the engineer Charles Liddell (c.1813-1894) and specialist railway architect Charles Henry Driver (1832-1900). In 1862 the decision was made to extend the line from Bedford to London which was again the responsibility of Liddell, except for the final fourteen miles into London and the design of the terminus at St Pancras (listed at Grade I) which was undertaken by William Barlow (1812-1902). Additional routes were then added from Chesterfield to Sheffield in 1870, and from Kettering to Corby in 1879. The most important changes to the infrastructure of the Midland Railway were the rebuilding of its principal stations and the increasing of the line’s capacity, involving the quadrupling of some stretches of the route south of the Trent from the early 1870s to the 1890s. Derwent Viaduct was built between 1836 and 1840 as part of the North Midland Railway. The route from Derby to Chesterfield and onwards to Rotherham and Leeds was surveyed by George Stephenson in 1835, and the Act of Parliament for the construction of the 72 mile line was obtained in 1836. Linked at Derby to the Birmingham & Derby Junction Railway and the Midland Counties Railway, it was to form part of a route from London to Yorkshire and the North East. George Stephenson was joined by his son Robert as joint Chief Engineer on the project in 1837. In order to concentrate on his mineral and mining interests, George relinquished his railway projects in 1839 so it was his son who saw the North Midland through to its completion in 1840. Part of Robert Stephenson’s skill in handling railway projects was his ability to select and manage an able team, and he entrusted much of the engineering design of the North Midland to Frederick Swanwick whose name appears on the surviving contract drawings. The Stephensons, supported by Swanwick, designed the line north from Derby to have gradients no greater than 1 in 250 to suit the low power of contemporary steam locomotives, which meant relegating Sheffield to a link line. To achieve such gradients the line followed the River Derwent as far as Ambergate and then ran through more difficult territory up the valley of the River Amber via Wingfield and Clay Cross to Chesterfield, then over to Rotherham and via Wakefield to Leeds. The notable sequence of picturesque stations along the line was designed by Francis Thompson who was therefore also influential in setting his stamp on the character of the line. The viaduct at Ambergate spans both the River Derwent and the Derby Turnpike (now the A6). It was erected by the contractor T. Jackson, who won the contract for this section with a tender of £63,000. The viaduct was illustrated in an early engraving of the line, reflecting its scale, public prominence and picturesque setting. The east face is as built but the north section of the west face was widened by the London Midland and Scottish Railway (LMS) in 1930-31 as part of line improvements around Ambergate, which was the junction for the main line via Matlock to Manchester. (The works included the construction of a separate viaduct with steel plate girder spans for the Manchester line, immediately west of Derwent Viaduct.) Details A five-span skew arched viaduct built in 1836-40 for the North Midland Railway to the designs of George and Robert Stephenson with Frederick Swanwick. MATERIALS: coursed quarry-faced Derbyshire gritstone with ashlar dressings and red brick soffits laid in English bond. Girders of riveted steel. EXTERIOR: the viaduct spans the Derby Road (A6) and the River Derwent. It has five broad skewed segmental arches on tall piers. From the south to the north end, it consists of one span over land, two spans over the River Derwent, and two spans over the A6. The east elevation has v-channelled stepped voussoirs that return as quoins on the soffits, and have slightly projecting dropped keystones. The arches spring from chamfered impost bands of picked stone with dressed margins that continue around the inside faces and which have integrated diagonally set springers. The soffits are constructed of skew-set red brick. The spandrels, piers and buttresses are faced with coursed quarry-faced stone laid in diminishing courses. The piers have a band dressed in the same way as the impost bands, and the pointed cutwaters are capped by a rounded ashlar prow. The viaduct has a boldly projecting moulded cornice and a low, ashlar parapet surmounted by C20, steel railings. At the north end this continues along a wing wall that steps out with quoins and follows the line of the railway. The west face is the same except for the alterations that were made in 1930-31 to accommodate a new track diverging at the north end. A steel plate girder was added across the two northern-most arches involving the extension of two piers and the abutment to support it. The extensions are faced with coursed, quarry faced gritstone, and are skewed. Sources Books and journals The North Midland Railway Guide, (1842) Bailey, M, Robert Stephenson - the Eminent Engineer, (2003) Biddle, G, Britain’s Historic Railway Buildings, (2003) Williams, F S, The Midland Railway: its rise and progress, (1886) Carter, O F, 'Back Track vol 9' in Francis Thompson 1908-95 - an architectural mystery solved, (April 1995) Other Alan Baxter & Associates, Midland Main Line Statement of History and Significance, 2013, Network Rail National Record Centre, barcode 3076530, 3076541,3076583, 3076584, 3076585, 3076587, 3076588, 3076589, Russell, S, North Midland Railway Lithographs.'