The Sapperton Canal Tunnel is a tunnel on the

Thames and Severn Canal 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 bett ...

near

Cirencester Cirencester (, ; see below for more variations) is a market town in Gloucestershire, England, west of London. Cirencester lies on the River Churn, a tributary of the River Thames, and is the largest town in the Cotswolds. It is the home of ...

Gloucestershire Gloucestershire ( abbreviated Glos) is a county in South West England. The county comprises part of the Cotswold Hills, part of the flat fertile valley of the River Severn and the entire Forest of Dean. The county town is the city of Gl ...

, England. With a length of , it was the longest tunnel of any kind in England from 1789 to 1811. Construction, following an

Act of Parliament Acts of Parliament, sometimes referred to as primary legislation, are texts of law passed by the Legislature, legislative body of a jurisdiction (often a parliament or council). In most countries with a parliamentary system of government, acts of ...

, began in 1784. Twenty-six shafts were dug along the line of the tunnel and workfaces dug in each direction eventually joining up before the diameter of the tunnel was expanded. Difficulties were encountered related to

strata In geology and related fields, a stratum ( : strata) is a layer of rock or sediment characterized by certain lithologic properties or attributes that distinguish it from adjacent layers from which it is separated by visible surfaces known as ei ...

Great Oolite The Great Oolite Group is a Middle Jurassic stratigraphic unit that outcrops in southern England. It consists of a complex set of marine deposits primarily mudstone and bioclastic ooidal and fine grained limestone, deposited in nearshore to she ...

(solid

limestone Limestone ( calcium carbonate ) is a type of carbonate sedimentary rock which is the main source of the material lime. It is composed mostly of the minerals calcite and aragonite, which are different crystal forms of . Limestone forms whe ...

) and

Fuller's Earth Fuller's earth is any clay material that has the capability to decolorize oil or other liquids without the use of harsh chemical treatment. Fuller's earth typically consists of palygorskite (attapulgite) or bentonite. Modern uses of fuller's ea ...

clay. These caused roof falls and narrowing of the channel which continued after the tunnel opened in 1789 and required frequent maintenance. The stone portals at either end are

listed building In the United Kingdom, a listed building or listed structure is one that has been placed on one of the four statutory lists maintained by Historic England in England, Historic Environment Scotland in Scotland, in Wales, and the Northern Irel ...

s. Boats passed through by legging until 1911. The canal was abandoned by 1933 and subsequent roof falls mean that it is no longer navigable.

Cotswold Canals Trust The Cotswold Canals Trust is a British registered charity that aims to protect and restore the Stroudwater Navigation and the Thames and Severn Canal. Formed in 1972, the organisation has a goal to restore navigability on the two waterways be ...

have proposed restoration.

History

The

was authorised by an

on 17 April 1783 but details of the tunnel had not been worked out, and arguments about its size continued for two to three months. Regular barges on the Severn were

trow A trow was a type of cargo boat found in the past on the rivers Severn and Wye in Great Britain and used to transport goods. Features The mast could be taken down so that the trow could go under bridges, such as the bridge at Worcester and ...

s which were wide; those on the Thames were Thames

barge Barge nowadays generally refers to a flat-bottomed inland waterway vessel which does not have its own means of mechanical propulsion. The first modern barges were pulled by tugs, but nowadays most are pushed by pusher boats, or other vessels ...

s, wide. The only long tunnel in the country at the time was

Harecastle Tunnel Harecastle Tunnel is a canal tunnel on the Trent and Mersey Canal in Staffordshire between Kidsgrove and Tunstall. The tunnel, which is long, was once one of the longest in the country. Its industrial purpose was for the transport of coal ...

, suitable for narrow boats just wide. A party of Commissioners from the Thames thought that the cost of a wide tunnel would be prohibitive, and that it should be built for narrow-beam boats, with the trows or barges unloading their cargos at each end of the tunnel. By late summer, the decision had been taken to build a broad tunnel, high and wide, and the company advertised for tunnellers in September. The tunnel would be long and below ground at its deepest point. It was expected to take four years to complete, beginning in early 1784. To speed the work, 26 shafts were sunk for many simultaneous workfaces, the deepest of which was . Small tunnels, known as headings, were dug in two different directions from the base of each shaft and the spoil lifted up the shaft and dumped in

Spoil tip A spoil tip (also called a boney pile, culm bank, gob pile, waste tip or bing) is a pile built of accumulated ''spoil'' – waste material removed during mining. These waste materials are typically composed of shale, as well as smaller quant ...

s above the route of the canal. A small temporary railway was later installed to take workers into the tunnel and remove waste materials. The use of explosives to expand the headings to the full size of the tunnel meant that acrid smoke and foul air built up. Chimneys were built in the shafts, with fires at their base to try to remove the foul air. The construction contract was awarded to Charles Jones, who managed to build about one third of it, but then had financial difficulties, and so other contractors were engaged to work on smaller sections. Difficulties during construction included different

(solid

) has water permeable fissure which led to rock falls and spring formation and, during dry periods, the water leaking out of the canal. In areas where the tunnel went through

clay it had to be lined with brick. When the Fuller's Earth expanded this could lead to roof falls and pushed up the base of the tunnel reducing the depth of water for the boats passing through it. The tunnel was opened on 20 April 1789, after five years of construction. It has no

towpath A towpath is a road or trail on the bank of a river, canal, or other inland waterway. The purpose of a towpath is to allow a land vehicle, beasts of burden, or a team of human pullers to tow a boat, often a barge. This mode of transport ...

; boats were propelled through the tunnel by legging. There were some defects in the workmanship, causing closure for ten weeks' repairs after a year. Further attempts to repair and stabilise the walls included the insertion of oak beams at the base to stop the sides of the tunnel moving inwards as the clay expanded and, in 1904, a concrete lining to some sections. It was superseded as the longest canal tunnel in England in 1811 by the

Huddersfield Narrow Canal The Huddersfield Narrow Canal is an inland waterway in northern England. It runs just under from Lock 1E at the rear of the University of Huddersfield campus, near Aspley Basin in Huddersfield, to the junction with the Ashton Canal at White ...

's Standedge Tunnel, at long, afterwards lengthened, that remains the highest, longest and deepest instance in

Britain Britain most often refers to: * The United Kingdom, a sovereign state in Europe comprising the island of Great Britain, the north-eastern part of the island of Ireland and many smaller islands * Great Britain, the largest island in the United King ...

– which only accommodates . Strood Tunnel on the

Thames and Medway Canal The Thames and Medway Canal is a disused canal in Kent, south east England, also known as the Gravesend and Rochester Canal. It was originally some long and cut across the neck of the Hoo peninsula, linking the River Thames at Gravesend with th ...

was when it opened in 1824, but was interrupted six years later by a short section to create a passing basin. The last commercial traffic passed through the tunnel in 1911 and in 1916 further roof falls occurred. The whole canal was abandoned by 1933. The tunnel was passable until at least 1966, but is now blocked by roof collapses over several hundred yards, mainly in sections where the ground is

fuller's earth Fuller's earth is any clay material that has the capability to decolorize oil or other liquids without the use of harsh chemical treatment. Fuller's earth typically consists of palygorskite (attapulgite) or bentonite. Modern uses of fuller's ea ...

. Restoration is proposed by the

as part of their project to re-open a direct route between Thames and Severn. The trust has operated

tourist Tourism is travel for pleasure or business; also the theory and practice of touring, the business of attracting, accommodating, and entertaining tourists, and the business of operating tours. The World Tourism Organization defines tourism mo ...

boat trips into the tunnel in winter months. The

Sapperton railway tunnel The Sapperton Railway Tunnel is a railway tunnel near Sapperton, Gloucestershire in the United Kingdom. It carries the Golden Valley Line from Stroud to Swindon through the Cotswold escarpment. It was begun by the Cheltenham and Great Wester ...

, on the Golden Valley Line, follows a similar route under the '

Cotswold Edge The Cotswolds (, ) is a region in central-southwest England, along a range of rolling hills that rise from the meadows of the upper Thames to an escarpment above the Severn Valley and Evesham Vale. The area is defined by the bedrock of Juras ...

'. There have been proposals to pump water from the

River Severn , name_etymology = , image = SevernFromCastleCB.JPG , image_size = 288 , image_caption = The river seen from Shrewsbury Castle , map = RiverSevernMap.jpg , map_size = 288 , map_c ...

toward the periodically water-stressed

Thames Basin The River Thames ( ), known alternatively in parts as the River Isis, is a river that flows through southern England including London. At , it is the longest river entirely in England and the second-longest in the United Kingdom, after the R ...

; if so the tunnel and canal eastward could be used for this.

Portals

The northern portal near Sapperton village was built between 1784 and 1789 by Josiah Clowes. It was restored in 1996. The southern Coates portal was built by the engineer Robert Whitworth and has

doric Doric may refer to: * Doric, of or relating to the Dorians of ancient Greece ** Doric Greek, the dialects of the Dorians * Doric order, a style of ancient Greek architecture * Doric mode, a synonym of Dorian mode * Doric dialect (Scotland) * Doric ...

columns and

vermiculated Vermiculation is a surface pattern of dense but irregular lines, so called from the Latin ''vermiculus'' meaning "little worm" because the shapes resemble worms, worm-casts, or worm tracks in mud or wet sand. The word may be used in a number of ...

masonry. It was restored in 1980.

In fiction

In ''

Hornblower and the Atropos ''Hornblower and the Atropos'' is a 1953 historical novel by C.S. Forester. Horatio Hornblower is posted to HMS ''Atropos'', the smallest vessel in the Royal Navy that merits command by a post-captain, as he salvages treasure from the Mediterra ...

'' by C.S. Forester, Hornblower helps the boatman "

leg A leg is a weight-bearing and locomotive anatomical structure, usually having a columnar shape. During locomotion, legs function as "extensible struts". The combination of movements at all joints can be modeled as a single, linear element ca ...

" through Sapperton Tunnel after the boatman's assistant is incapacitated. Forester spends the first two chapters of the book on the canal-boat journey, Roughly a third of the first chapter is devoted to the tunnel. In the novel '' Gone'' by

Mo Hayder Beatrice Clare Dunkel (born Clare Damaris Bastin; pen names, Mo Hayder and Theo Clare; 2 January 1962 – 27 July 2021) was a British author. Earlier in her life she worked as an actress and model under the name Candy Davis. She went on to wr ...

the tunnel is used extensively as a location in this crime thriller. An episode of Midsomer Murders titled ''The Green Man'' (series 7 episode 1) was partly filmed at the tunnel. The tunnel plays a significant part in ''Slaughter in the Sapperton Tunnel'' by Edward Marston. ISBN 978-0-7490-2681-3

Coordinates

References

Bibliography

* * * * * *

External links

Current state of the tunnel and restoration plans Stroud Voices (Canal tunnel selection) - oral history site
* {{s-end Canal tunnels in England Canals in Gloucestershire Tunnels completed in 1789 Tunnels in Gloucestershire 1789 establishments in England Disused tunnels Thames and Severn Canal