Somerset Coal Canal
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A feature of the canal was locks .
The Radstock arm was never commercially successful and was replaced first with a tramway in 1815[1] and later incorporated into the Somerset and Dorset Joint Railway. The Paulton route flourished for nearly 100 years and was very profitable, carrying high tonnages of coal for many decades; this canal helped carry the fuel that powered the nearby city of Bath. By the 1880s, coal production declined as the various pits either ran out of coal or were flooded and then closed. In 1896 the main pump at Dunkerton, which maintained the canal water level, failed. The resultant lowering in level meant that only small loads could be transported, which reduced revenue, thus the canal company could not afford a replacement pump. The canal became disused after 1898 and officially closed in 1902, being sold off to the various railway companies who were expanding their networks. In September 2014, restoration work began on the canal section from Paulton to Radford, with the aim of restoring the entire canal to navigation in the future. The largest canal drydock in England has been revealed at Paulton; culverts and bridges nearby are being reinstated or rebuilt; and about 2⁄3 mile (1 km) of canal from Paulton to Radford has been in water since mid-2015.[2] HistoryBackgroundIn 1763 coal was discovered in John Rennie who presented the report on 14 October 1793 estimating the cost of construction of the canal at £80,000. Smith, who also worked at the Mearns Pit at High Littleton, made the original observations leading to his important stratification theory by observing the dips in the geological strata through which the canal was cut.[5][6] Smith became Surveyor to the company, but was dismissed in April 1799, apparently because he had used his position as surveyor to buy a local house at advantageous terms.[7] He then set himself up in a private practice in Bath but was re-engaged by the company in 1811, to provide advice when repairs became necessary to the canal bed.[8]
The canal was authorised by an Bradford, in the county of Wilts" of 1794,[3] and further detailed surveys were carried out by Robert Whitworth and John Sutcliffe, who was then appointed as chief engineer.
ConstructionIn May 1795, tenders were invited for the first section to be built from the meadows near Goosehard (or Gooseyard) near Paulton to Hopyard in the parish of Camerton. In June 1795 a contractor, Houghton & Son from Shropshire, started the terminus at Paulton meadows using local labour. This first section of the canal was completed on Monday 1 October 1798; the first load of coal carried on the canal was delivered to Bath via Dunkerton. Some 14 collieries at Timsbury and Paulton were connected to their respective basins in the meadow terminus by tramways; this required the construction of three tramway bridges over the Cam brook. A further bridge at Upper Radford was required over the canal; at this point tramways connected the Withy Mills and Radford workings. The course of the Cam brook was modified at various places to protect the canal from erosion. In 1799 William Whitmore and his partner, Norton, offered to build a balance (or geometrical) lift without payment, on condition that if successful they were to have £17,300 and a royalty of 4 pence per ton of goods passed.[9] The design of the Wilts and Berks Canal, on the grounds that the price of coal to their customers would be too high. After negotiation, the company obtained a new Act of Parliament on 30 April 1802, which authorised the formation of a separate body called "The Lock Fund of the Somerset Coal Canal Company", with powers to raise the sum of £45,000. The money was raised by the Kennet and Avon, the Wilts and Berks and the Somerset Coal Canal each contributing £15,000, and the one shilling surcharge was to be levied until the capital had been repaid, after which it would cease.[10] The act set the tonnage rates to be charged:
The boats were weighed at Midford, where a weigh house was built in 1831. Boats were floated into a one-ended lock, the gate closed and the water drained. This left the boat resting on a cradle suspended by angled rods attached to a beam which took the weight of the boat. One-pound weights were then added to a pan, with one pound being equivalent to one hundredweight (112 pounds or 51 kilograms), until the system was in equilibrium, then the weight was recorded. The weigh house at Midford was one of only four known to have been built in England and Wales.[3]
OperationThe canal opened in 1805 The Radstock branchWhen the Radstock branch was constructed, it was intended to link it to the main line of the Paulton branch at Midford, which was at a lower level at this point. The Lock Fund created in 1802 was to have paid for the construction of the locks, but because there was little regular traffic on the branch, the company built one lock, an aqueduct over the Midford Brook, and a short tramway to bridge the gap.[10] This contributed to the economic failure of the branch, and its replacement by a tramway in 1815.[17] The tramway was laid along the former canal's towpath. It was single-line with passing places every 600 yards (550 m), and was originally laid using cast iron plates on stone block sleepers, but was relaid using wrought iron plates.[3] Engineers and surveyors
Data from Jim Shead's Waterways Information.[9] Combe Hay and the caisson lockThe fall over the route is 135 ft (41 m), which meant problems with supplying adequate water. The narrow boat travelling through the series of locks (22 of them each 6 ft (1.8 m) deep) with a 25-ton load of coal caused 85 tons of water to be discharged into the brook below the locks. As a result, the canal was designed with all 22 locks in one flight near Combe Hay and a pumping engine to raise water from the Cam; this was the first canal to depend entirely on pumping.
A potential solution to the water supply problem was the use of caisson locks as proposed by George IV ), but had engineering problems and was never successful commercially or built elsewhere.
It was temporarily replaced with an Boulton & Watt Steam Pumping Station, capable of lifting 5,000 tons of water in 12 hours, were built to the latest design with metal plate clad wooden gates.[18][19][20]
ConstructionThe two images show a spillway drain from c. 1796 (uncovered in 2009–10) at Upper Midford, a location where a caisson to take the canal from the 180 ft (55 m) level to the 134 ft (41 m) level at Midford Aqueduct was proposed. Each caisson would have had such a drain for maintenance purposes over the exit arch made to the same dimensions. The following extract from the Bath Herald newspaper provides the details of the chosen sites:
For further Newspaper articles see s:Bath Georgian Newspaper - Somerset Coal Canal Paulton and Timsbury basinslocated between the villages of Paulton and Timsbury was the terminus of the northern branch of the Somerset Coal Canal and was a central point for at least 15 collieries around Paulton, Timsbury and High Littleton, which were connected to the canal by tramroads. Timsbury basin was some 600 ft (180 m) to the west of Paulton basin. On the northern side of Timsbury basin was the terminus for the tramroads which served Old Grove, Prior's, Tyning and Hayeswood pits, with a branch line to Amesbury and Mearns pits. Parts of this line were still in use in 1873, probably all carrying horse-drawn wagons of coal. Tramroads on the southern side of the Paulton basin served Brittens, Littleborrok, Paulton Ham, Paulton Hill, Simons Hill terminating at Salisbury Colliery. In addition the Paulton Foundry used this line. The entire line was disused by 1871 as were the collieries it served.[16] The area has been designated as an 'area of special architectural or historic interest, the character or appearance of which it is desirable to preserve or enhance' under section 69 of the Planning (Listed Buildings and Conservation Areas) Act 1990.[21] Coming of the railwayThe first railway to affect the canal was the Hallatrow to Camerton, running alongside the canal for the last 1+1⁄2 miles (2 km) of its route.[3]
The Present dayThe route of the canal lies in a largely agricultural area, dotted with small villages linked by minor roads.[24] Several stretches of the Paulton and Timsbury basins branch are easily visible, and various stretches and features were surveyed in 2014.[citation needed] Full restoration of the entire length from Paulton to Dundas is being explored.[by whom?] Four locks on the original canal route at Combe Hay have been buried; one by a 20-foot (6 m) railway embankment, and three overfilled by 10 to 20 feet (3–6 m) with building waste since the 1960s. It may no longer be feasible to reinstate the original locks 16, 17, 18 and 19 structures for this section.[why?] At Upper Midford the canal is blocked entirely at the accommodation bridge[25] by the 40-foot (12 m) high embankment of the railway that crosses it.[26] Most of the canal features along the entire route are on private land but the towpath survives in places as a right of way, while the later railway between Midford to Wellow has been surfaced to form part of National Cycle Route 24.[27] It has been proposed[by whom?] that a statue, commissioned by Sustrans, of William Smith, the father of English Geology, will be sited next to the path on the line of the canal commemorating his work as its surveyor and his recognition of the significance of rock strata. Restoration worksLimpley StokeThe 1⁄4-mile (400 m) stretch at Brassknocker Basin where the canal joins the Kennet and Avon at Dundas Aqueduct was restored during the 1980s and is now a thriving marina with moorings. Excavations of the old stop lock (at the junction with the Kennet and Avon Canal) showed that this had originally been a broad (14 feet, 4.3 m) lock that at some point was narrowed to 7 feet (2.1 m) by moving the lock wall.[3] Paulton and Timsbury basinsWork started in 2013 to reveal and excavate the drydock next to the eastern Paulton Basin. This drydock appears to be the largest drydock anywhere on the canal system in England, being about 30 feet (9.1 m) wide and 83 feet (25 m) long, large enough for three full-length narrowboats to be worked on at the same time.[28] The drainage culvert at the southeast corner of the drydock was rebuilt in December 2013, and the drydock itself completely excavated in April 2014. The entrance to the drydock, at the western end, was surmounted by a bridge, partially demolished in 2002 but rebuilt during 2014.[28] Withy MillsExcavations began in May 2014 at Terminus Bridge; the abutments were found to be in poor condition; an earth bund between the abutments carried the public footpath and stopped the water draining from the Paulton and Timsbury Basins. A new earth bund was installed about 25 m (27 yd) west of Terminus Bridge to stop the water and allow work to continue on the bridge.[29] During excavations a drainage culvert was discovered about 20 m (22 yd) west of Terminus bridge.[30] Work resumed in September and November 2014 to batter and reshape the canal embankments. Excess topsoil was removed and the towpath reinstated on the stretch to the east from Terminus bridge for about 200 m (220 yd). On the same stretch a retaining wall was discovered in the south embankment continuing for about 100 m (110 yd), possibly built as a repair to a weak section of canal banking. Vertical infills of white clay have been used along this wall. Grant to study history of the canalThe canal has been studied for many years with exploration and restoration work being undertaken in Wellow and elsewhere. Particular effort, so far unsuccessful, has been put into trying to find the site of the second and third caisson locks at Combe Hay. In October 2006 a grant of £20,000 was obtained from the Route and points of interest
See also
References
Bibliography
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