The Thames and Severn Canal is a canal in Gloucestershire in the south-west of England, which was completed in 1789. It was conceived as part of a cargo route from Bristol and the Midlands to London, linking England's two largest rivers for better trade. The route climbs the steep Cotswold escarpment through the Golden Valley, tunnels underneath the summit of the Cotswold Edge, and emerges near the source of the Thames.
At its eastern end, it connects to the top of the navigable Thames at Inglesham Lock near Lechlade, while at its western end, it connects to the Stroudwater Navigation at Wallbridge near Stroud, and thence to the River Severn. It had one short arm (branch), from Siddington to the town of Cirencester. It includes Sapperton Tunnel, which when built was the longest canal tunnel in Britain, and remains the second-longest complete tunnel. There were always problems with water supply, as no reservoirs were built, while the summit section near the tunnel ran through porous limestone, and there were constant difficulties with leakage. Competition from the railways took much of the canal's traffic by the end of the 19th century, and most of the canal was abandoned in 1927, the remainder in 1941.
Since 1972, the Cotswold Canals Trust has been working to restore both the canal and the Stroudwater Navigation to navigably re-link the Thames and the Severn. A number of the structures have been restored, and some sections are now in water. A major step forward occurred in 2003, when a bid was made to the Heritage Lottery Fund for £82 million to restore both canals. The bid and the project had to be split into smaller sections, but £11.9 million was awarded in 2006 for Phase 1A, which with matched funding has restored from The Ocean at Stonehouse to Wallbridge on the Stroudwater Navigation, and from there to Stroud Brewery on the Thames and Severn Canal. The Phase 1B reconnection to the national waterways network at Saul Junction is expected to be completed by 2025, connecting the Severn with the Golden Valley for the first time in a century.
In 2010, British Waterways gave Inglesham Lock to the Trust, and the Inland Waterways Association mounted a national campaign to fund its restoration (and of canal above). To re-open the whole canal some major engineering obstacles will need to be overcome.
History
Since the 1730s, when the first Act of Parliament to authorize a canal from the River Severn to Stroud had been passed, the Stroudwater Navigation had been seen as part of a larger plan to link London and Bristol by waterway. No work took place immediately, but the Stroudwater was eventually opened in 1779, and within two years the shareholders commissioned a survey for a canal from Dudbridge to Cricklade, which would complete the link. It is likely that John Priddy – previously the engineer for the Stroudwater scheme – carried out the survey, but others were soon involved including Sir Edward Littleton, who was connected with the Staffordshire and Worcestershire Canal. Priddy suggested that there were better terminal points at Wallbridge and Lechlade. Robert Whitworth then surveyed two routes, the first as suggested by Priddy, and the second direct from the Severn to the Thames following the valley of the River Coln. The first route was chosen, based on excellent water supplies at Cirencester, although the estimates of the amount of water available proved to be wildly optimistic.
The estimated cost of the project was £127,916, most of which was promised within three weeks. The bill to authorise the canal passed through Parliament relatively easily, and became an Act on 17 April 1783. The company could raise an initial £130,000, with an additional £60,000 if required. The canal was to be suitable for boats wide, and so could accommodate Thames barges, but not Severn Trows. Josiah Clowes was appointed head engineer, surveyor and carpenter to the canal in 1783 to assist Whitworth. Clowes became resident engineer and was paid £300 per year. Clowes' work on the canal gave him a reputation that made him highly sought after in the last five years of his life. He left the construction of the canal shortly before completion to work on Dudley Tunnel.