Кромфордский канал: История и значение промышленного водного пути Дербишира

The Cromford Canal ran 14.5 mile (23 km) from Cromford to the Erewash Canal in Derbyshire, England with a branch to Pinxton. Built by William Jessop with the assistance of Benjamin Outram, its alignment included four tunnels and 14 locks. From Cromford it ran south following the 275 feet (84 m) contour line along the east side of the valley of the Derwent to Ambergate, where it turned eastwards along the Amber valley. It turned sharply to cross the valley, crossing the river and the Ambergate to Nottingham road, by means of an aqueduct at Bullbridge, before turning towards Ripley. From there the Butterley Tunnel took it through to the Erewash Valley. From the tunnel it continued to Ironville, the junction for the branch to Pinxton, and then descended through fourteen locks to meet the Erewash Canal at Langley Mill. The Pinxton Branch became important as a route for Nottinghamshire coal, via the Erewash, to the River Trent and Leicester and was a terminus of the Mansfield and Pinxton Railway. A 6 mile (10 km) long section of the Cromford canal between Cromford and Ambergate is listed as a Biological Site of Special Scientific Interest (SSSI) and a Local Nature Reserve. In addition to purely canal traffic, there was a lively freight interchange with the Cromford and High Peak Railway, which traversed the plateau of the Peak District from Whaley Bridge in the north west, and which descended to the canal at High Peak Junction by means of an inclined plane.

At the end of the eighteenth century an extension was proposed to the Erewash Canal by various interested parties who wished to encourage coal mining further north. The suggestion was declined by the canal company, so local businessmen, including Benjamin Outram's father Joseph, Benjamin decided to go ahead on their own, asking William Jessop to design one between Langley Mill and Cromford, with a branch to Pinxton. This would carry coal to Cromford, which was becoming industrialised, and limestone from the area for the growing iron industry. Also important would be lead from Wirksworth and cotton from the Cromford mills. The connection to the Erewash Canal would provide an outlet to the Trent and Mersey Canal and the rest of the country. The canal therefore attracted the support of some powerful figures such as Philip Gell of Hopton Hall and Sir Richard Arkwright the latter initially at least. Matters were taken out of the Erewash Canal owners hands, for, without their co operation, there was the implicit threat that a competing canal would be built to the Trent. The major opposition came from the water powered mill owners along the Derwent, of which there were many, downstream of the proposed canal, fearful of loss of flow in dry weather. Since, between Cromford and Pinxton, the canal would be level, Jessop was able to give reassurance, carefully downplaying the problem of the descent, with its locks, to Langley Mill. However, with the assistance of Benjamin Outram, he also spent over a year measuring the flow rate of the Derwent, a precaution which was invaluable when the bill was placed before Parliament. He also proposed to make the summit pound deep enough that it could be replenished on Sundays when the mills were closed, and hold enough water to supply the locks for a week even in the driest weather. The length from the Erewash Canal would be built to match, accessible to barges from the Trent. Through the Butterley Tunnel and along the narrow Derwent valley it would be to narrow boat standards, similar to the Trent and Mersey. At the last minute before the Bill was to be presented to Parliament, Richard Arkwright raised a problem. The assumption had been that water would come from Cromford Sough, the drainage from the Wirksworth lead mines. Arkwright complained that the canal crossed his land and insisted that water should be obtained from the river by raising the height of the weir at Masson Mill. This was an unwelcome complication (which would mainly benefit Arkwright himself and his mill) but the canal Committee reluctantly agreed.

The canal obtained its Act of Parliament in 1789. Perhaps because they had quoted too little, basing their estimates on Jessop's cost predictions which may themselves have been too optimistic, the contractors soon found themselves in financial difficulties and, at the end of 1790, simply walked off the site. Benjamin Outram hastily took over full management control and was awarded a salary increase. In January 1792 there was a problem when the Amber Aqueduct failed but, by May, the canal to the east of Butterley was virtually complete and most of the earthworks to the west. The Butterley Tunnel was excavated by first sinking 33 shafts, about apart as much as deep to give a number of working faces. Most of the heading was through soil, with some coal measures and iron ore deposits, the final tunnel being lined through most of its length. By 1793 the company had a balance in hand of only £273 and the cost had risen to half as much again as Jessop's original estimate. Nevertheless, the canal was showing an income, unfinished though it was. In August, however, there were problems with the Derwent Aqueduct which required considerable modification. The spandrel walls had parted due to the horizontal forces imposed by the canal, and a longitudinal split had opened up in the arch. In his report to the canal committee, Jessop gave his opinion that the use of Crich lime, being unusually pure, had delayed the setting of the mortar. Later writers, with the benefit of engineering knowledge acquired after Jessop's time, have suggested that the spandrel walls were simply too slender for the forces imposed. At any rate, the arch was partly dismantled and steel tie bars and lateral reinforcing arches were installed, together with external buttresses. This Jessop did at his own expense. In the end, despite costing about twice the initial estimate of £42,697 (£ in ), the canal opened in 1794 and was a financial success.

In 1802 the canal had carried over 150,000 tons and by 1842 nearly 300,000, then in 1849, the Manchester, Buxton, Matlock and Midlands Junction Railway was built alongside as far as Ambergate, which reached Manchester in 1867. A further line to Pye Bridge was built in 1875. By 1888 trade had shrunk to 45,000 tons a year. In 1846, parliamentary assent was granted to merge with the MBM&MJR. The sale was not carried through until 1852 by which time the Midland Railway and the LNWR had assumed joint control and, with railway lines from Rowsley through Ambergate to the north and south, it was being used for little more than local traffic. In 1889, subsidence closed the Butterley Tunnel for four years, and further subsidence in 1900 closed the Tunnel permanently. Most of the canal was abandoned in 1944 with the exception of a half mile (800m) stretch to Langley Mill which was abandoned in 1962. The Bullbridge Aqueduct was removed in 1968 when the Ripley road was widened. In 1985 the Codnor Park Reservoir was lowered by 6 feet (2 m) and a lock was removed as part of a flood prevention scheme.

After closure, the canal was taken over by the British Waterways Board and acquired by Derbyshire County Council in 1974. Between 1968–69 and 1989 the 5 miles between Cromford and Ambergate were restored either partly or wholly by the Cromford Canal Society [CCS] together with the beam engine (the Leawood Pump) which was restored to full operation, pumping water from the River Derwent to the Canal above. CCS ran horse drawn passenger boats (up to 15,000 passengers a year) on the 1½ mile section from Cromford to Leawood and steamed the beam engine on regular occasions. The lower section from Leawood to Leashaw (through Gregory Tunnel) was restored to navigation but storm damage to embankments prevented its use. CCS ceased to exist in 1990 and this part of the canal has nearly reverted to pre restoration condition. Attempts are being made to restore the canal and about 5 mile (8 km) of it remains in water. In March 2013 dredging began on a 1.3 mile (2 km) length between Leawood Pumphouse and Cromford Wharf with the aim of making it navigable for narrowboats. This section is now open for trips on an historic cargo narrowboat, Birchwood, now electric powered. The towpath from Ambergate to Cromford is now a very popular walking route, with the Derwent Valley Line adjacent, Leawood Pump House and the High Peak Junction of the Cromford and High Peak Railway.

The Friends of the Cromford Canal is a charitable organisation whose aim is to see the restoration of the Cromford Canal for the benefit of the general public. The society promotes the restoration of the Canal to navigation, and to connect it to the national inland waterway system at the junction with the Erewash Canal at Langley Mill. The group runs a trip boat, Birdswood, between Cromford Wharf and Leawood Pump House, although even after dredging of the section in 2013 it is quite shallow. English actor Brian Blessed is the president of Friends of the Cromford Canal. His voice gives the recorded safety announcement for the tripboat Birdswood on the Canal.