Listed Building: DARLEY ABBEY WEIR (1420572)

SUMMARY OF BUILDING Weir structure spanning the River Derwent, constructed in c1782 for Boars Heads Mills at Darley Abbey, incorporating a fish weir. REASONS FOR DESIGNATION Darley Abbey Weir, constructed c1782, is listed at Grade II for the following principal reasons: * Architectural interest: as a key component in the water management of the Grade I listed Darley Abbey Mills complex, comparable to other listed weirs in its date, size, construction and concave form; * Intactness: as an essential component of the water management system that controlled the Grade I listed mills at Darley Abbey and the contribution it played in the production processes performed at the mills; * Historic interest: for its association with the developments in processes pioneered by Richard Arkwright and his partners at Cromford and around the Derwent Valley at the peak of the Industrial Revolution and for its contribution to the international heritage significance of the Derwent Valley Mills World Heritage Site; * Group value: for the strong group value it holds with the Darley Abbey Mills South Complex (Grade I), Darley Abbey Mills North Complex (listed at Grade II & II*), associated mill workers’ housing to the west (Grade II), and the Derwent Valley World Heritage Site. HISTORY The industrial roots of Darley Abbey date back to the monastic period, when it was an industrial hamlet, with fulling mills, corn mills, and a forge. By the early 1770s, Darley Abbey held five water-powered mills, including a paper mill, a corn mill, two flint mills (for porcelain production) and a leather mill, all on the west bank of the River Derwent. The Evans family were established industrialists and bankers, and Alderman Evans held industrial interests in Darley Abbey since at least 1746 when he acquired a fulling mill and dye house. It was not until the 1770s that his son-in-law Thomas Evans and his brother the Reverend Edmund Evans began the purchase of land holding at Darley Abbey, developing the Evans industrial estate. Thomas Evans was an associate of Richard Arkwright, who had successfully developed a machine for spinning cotton in the 1760s, and had built a large industrial milling complex north of Darley Abbey in the Derwent Valley at Cromford in the 1770s. The Evans family was also related by marriage to the Strutt family who had textile mills nearby in Belper, Milford and Derby. The land east of the River Derwent at Darley Abbey was acquired by Thomas Evans in 1778, and Richard Arkwright persuaded Evans to build and operate a cotton mill using Arkwright’s patented machinery. Evans developed the Darley Abbey site as ‘Boar’s Head Mills’ between 1782 and 1830, the name is derived from the Evans family crest. By 1789, the Derwent Valley had the largest concentration of mills working on the Arkwright principle in Britain. The weir was constructed in c1782, as well as a masonry bridge linking the village on the west bank with the new mills on the east bank of the river. The masonry bridge was replaced in the mid C19 by a bridge built on cast-iron columns, and this superstructure was replaced by concrete in the 1930s. The weir was constructed diagonally across the river Derwent to regulate the flow of water to the Boars Head Mills, and control the direction of its flow downstream. In order to obtain the adequate volume of water, the river was dredged from Allestree Ford, providing the Evans with a high quality sediment by-product to sell as a building material and to Derby Corporation for sanding tram lines in bad weather. Two sluice gates helped provide a consistent flow of water, being opened and closed according to the abundance or scarcity of the water supply. Photos reproduced in Don Peters’ Darley Abbey (1974) show two C19 metal gates on a winding mechanism, and these have since been replaced. From the pool created by the weir, water was channelled through the wheelhouse, turning the waterwheel and thereby driving the machinery. The water-powered cotton mills at Darley Abbey specialised in the production of quality thread for sewing, embroidery and haberdashery. The Evans’ involvement in the cotton mills ceased with the death of Walter Evans II in 1903, and textile production at the mill complex concluded in 1970. Darley Abbey Mills South Complex was first listed in 1967, amended in 2002 (Grade I), and includes the Long Mill, the Middle Mill, the East Mill, the West Mill, the Engine House and Chimney, the Tollhouse, the Bobbin Shop and the Drying Shed. Darley Abbey Mills North Complex includes the North Mill, Engine House and Boiler House (Grade II), fire station (Grade II), and Preparation Building (Grade II*). This mill complex is part of the Derwent Valley Mills World Heritage Site, a 15 mile stretch of industrial settlements from Matlock Bath in the north to Derby in the south. The four principal industrial settlements of Cromford, Belper, Milford and Darley Abbey are articulated by the River Derwent, the waters of which provided the power to drive the cotton mills. The Derwent Valley is recognised as being the cradle of the industrial revolution, where new types of buildings were erected to house the new technology for spinning cotton developed by Richard Arkwright in the late C18. The north weir, footbridge, fish weir and south weir are identified on the 1882 and 1900 Ordnance Survey maps. In 2014 a modern fish weir was constructed east to west across the natural island which lies between the northern and southern sections of the weir. An archaeological watching brief identified timber posts set into the river bed with layers of brushwood and stone. The dating of the timbers suggests a substantial man-made structure was constructed in the River Derwent in the late C15. A footbridge following the line of the weir south of the island is a C21 replacement, as is a timber post and rail fence which sits above the weir. DETAILS A weir, constructed in c1782, situated in the River Derwent, to the immediate west of the former Boars Head Mills, listed at Grade I. MATERIALS: coursed square gritstone blocks. EXTERIOR: the weir, constructed in c1782, is situated in the River Derwent, to the immediate west of the former Boars Head Mills, listed at Grade I. The weir complex measures approximately 110m in length, and comprises a two-part weir structure constructed of coursed square gritstone blocks. To the north is a concave sharp-crested weir curving upstream measuring approximately 20m in length, and a stepped spillway to the south measuring approximately 40m in length. To the south of the spillway is a coursed gritstone block wall running perpendicular to the spillway, containing two floodgates. The floodgates are joined to a natural island to the south (which is excluded from this assessment). The height of the weir is approximately 1.8m, and the floodgates have a depth of 1.2m. To the south of the island is a sharp-crested weir and fish weir measuring approximately 25m in length. Above the weir is a C21 footbridge on metal supports. The north and south weirs are linked by a stone wall revetment running around the northern and western edges of the island topped by a C21 post and rail timber fence*. On the north western edge of the island the modern fish weir* cuts through the wall but the stone was retained, and on completion of the weir the stone work was reconstructed to match the original form. The C21 footbridge* following the line of the weir south of the island and the timber post and rail fence* which sits above the revetment wall around the island are not considered to be of historic or architectural interest. The weirs form part of a larger water management system associated with the late C18 Boars Head Mills at Darley Abbey, which also includes mill races from the River Derwent to the mill complex, sluice gates and tail races from the mill complex to the river. Only the weirs have been assessed for designation. *Pursuant to s.1 (5A) of the Planning (Listed Buildings and Conservation Areas) Act 1990 (‘the Act’) it is declared that the C21 fish pass and footbridge, the metal supports of the footbridge and the post and rail fence on the island revetment wall are not of special architectural or historic interest. SELECTED SOURCES Books and journals: Peters, Don, Darley Abbey: from monastery to industrial community, (1974) Websites: Darley Valley Mills World Heritage Site, accessed from http://www.derwentvalleymills.org/index.php/history/key-sites/78-darley-abbey-mills- Derby Conservation Area : Darley Abbey, accessed from http://www.derby.gov.uk/media/derbycitycouncil/contentassets/documents/conservationareas/DerbyCityCouncil-DarleyAbbeyConservationArea.pdf Weir, Darley Abbey, Derby, accessed from http://www.heritagegateway.org.uk/Gateway/Results_Single.aspx?uid=MDR9753&resourceID=1023 Other: Menuge, Adam, Research Department Report Series no. 35/2006: Boar’s Head Mills, Darley Abbey, Derby. A Survey and Investigation of the Cotton Mills and Ancillary Buildings, 2006,