The River Stour ( (rhyming with either "tower" or "sour") is a major river in eastern England. It is long and forms most of the county boundary between Suffolk to the north, and Essex to the south. It rises in eastern Cambridgeshire, passes to the east of Haverhill, through Cavendish, Sudbury, Bures, Nayland, Stratford St Mary and Dedham. It becomes tidal just before Manningtree in Essex and joins the North Sea at Harwich.
The entire non-tidal river above Manningtree is designated as the Dedham Vale National Landscape, formerly known as an Area of Outstanding Natural Beauty. It has been painted by a number of prominent artists, including John Constable and Thomas Gainsborough.
The river was improved for navigation following the passing of an act of Parliament, the River Stower Navigation Act 1705 (4 & 5 Ann. c. 2). Locks were built to enable lighters to reach the town of Sudbury. Most of the locks were associated with mills, and the original 13 flash locks and 13 pound locks were replaced by 15 pound locks in the 19th century. The river was reasonably profitable at the beginning of the 19th century, but the advent of the railways led to a steady decline from 1852 onwards. Attempts to abandon it were thwarted by legal difficulties, but in 1914 the River Stour Navigation Company declared itself bankrupt, and the river soon became moribund.
From 1928 onwards, the river became a major source of drinking water, with South East Essex Waterworks (now Essex and Suffolk Water) extracting water at Langham and then Stratford St Mary pumping stations. As the demand for water grew, the Ely-Ouse to Essex Transfer Scheme was implemented, with water from the River Great Ouse discharged into the upper reaches of the river, and extracted again by the pumping stations. A third extraction point was added near Brantham, so that volumes of water flowing through Flatford could be maintained at a higher level for the benefit of tourists. To prevent salt water entering the river valley, sluices and a barrage were built at Cattawade, preventing boats from entering the river from the estuary.
The River Stour Trust was set up in 1968 to campaign for greater use of the river for navigation. It has worked to refurbish four locks, and to run boat trips from Flatford and Sudbury. The river can be used by unpowered craft between Sudbury and Cattawade, but powered boats are normally only allowed between Sudbury and Henny Mill, although the Trust has permission to run an electric boat at Flatford. Canoes and kayaks have to be portaged around the former locks where these have been replaced by fixed weirs and sluices.
Etymology and usage
The name is of uncertain and disputed origin. The river does not have a uniform pronunciation, varying from stowr to stoor.
On one theory, the name Stour derives from the Celtic sturr meaning "strong". However, the river-name Stour, common in England, does not occur at all in Wales;O.G.S. Crawford, "Celtic place-names in England", The Archaeological Journal (British Archaeological Association) 2nd ser. 27 1920: p. 144 Crawford noted two tributaries of the Po River near Turin, spelled Stura. In Germany the Stoer is a tributary of the River Elbe. According to Brewer's Britain and Ireland the Stour is pronounced differently in different cases: the Kentish and East Anglian Stours rhyme with tour; the Oxfordshire Stour is sometimes rhymed with mower, sometimes with hour, and the Worcestershire Stour always rhymes with hour.Ayto, John and Crofton, Ian: Brewer's Britain and Ireland, London: Weidenfeld and Nicolson, 2005, , p.1059.
As against that, stour is a Middle English word with two distinct meanings and derivations, still current enough to appear in most substantial dictionaries. As an adjective, with Germanic roots, it signifies "large, powerful" (in present-day Scandinavian languages stor means "big, great"). As a noun, from medieval French roots, it signifies "tumult, commotion; confusion" or an "armed battle or conflict". Wiktionary also adds "blowing or deposit of dust", the primary definition in the Concise Oxford Dictionary, which adds that this is a northern English and Scottish usage of uncertain derivation.Concise Oxford Dictionary, 10th edition, Oxford, 2001, , p. 1415 In 2006 it has been suggested that an Old European river-name was taken for an Old English adjective and that stour came to represent one pole of a structural opposition, with blyth at the opposite pole, allowing Anglo-Saxons to classify rivers on a continuum of fierceness.Richard Coates, "Stour and Blyth as English river-names" English Language and Linguistics 10 Cambridge University Press (2006:23-29).
The Victorian etymologist Isaac Taylor proposed a very simple solution: that Stour derives from dŵr, the Welsh word for water.Taylor, Isaac: Words and Places, London, 2nd edition, 1921, p. 143, accessed July 2009
It is quite possible that the various Stours do not share a common origin and that they need to be considered in their own terms rather than as a single problem. Certainly there is currently no universally-accepted explanation.
Description
The river rises in Wratting Common, Cambridgeshire, to the south of Weston Colville, and passes near Great Bradley where it is joined by Kirtling Brook. It continues through Little Thurlow, Great Thurlow, Great Wratting, and Kedington before passing to the east of Haverhill, where the county boundary between Suffolk and Essex starts to follow its course. The villages of Wixoe, Stoke-by-Clare, Clare and Cavendish are all on the left bank of the river. The River Glem joins it on the left bank, before it passes to the west of Long Melford and then skirts the western and southern edges of Sudbury. It is crossed by the A131 road at Ballingdon Bridge, to the south-west of Sudbury, below which it is officially navigable. It continues through Bures and to the south of Nayland to reach the western edge of Stratford St Mary. Dedham is on the south bank and Flatford on the north bank. To the south of Brantham the river becomes tidal below Cattawade barrage, after which it opens out to become an estuary near Manningtree, and runs along the southern side of the Shotley Peninsula. The international port of Harwich is on the south bank, and it is joined by the River Orwell as it reaches the sea to the east of Harwich.
The river from Cattawade barrage to Orwell Haven is tidal and used by large ships. The channel is dredged to , and this section should only be navigated by those experienced in tidal river navigation. Coasters travel up the river as far as the quay at Mistley.
History The earliest known settlement on the river in Suffolk was at Great Bradley, where human occupation has been recorded for over 5,000 years. During the Anglo-Saxon era, the river became the boundary between the Kingdom of the East Saxons and the Kingdom of East Anglia. The Life of King Alfred records a naval battle taking place at the mouth of the river, near Harwich in 884 or 885, where Alfred the Great defeated a force of 13 Viking ships.
Environmental issues Landscape The threat of large scale housebuilding in a scenic and relatively sparsely populated area, led to the river valley above Manningtree being designated the Dedham Vale National Landscape (formerly termed an Area of Outstanding Natural Beauty). The designated area is named after the village of Dedham in Essex. It is an area of rural beauty on both sides of the river, covering around in total.
The valley is directly accessible by rail from London and Colchester, but people wishing to travel from Ipswich must change. The valley is generally poorly connected by road to the Suffolk coast.Field Studies Centre https://www.field-studies-council.org/locations/flatfordmill/ The area was better connected, before the closure of most of the Stour Valley Railway in 1967.
The Stour valley has been portrayed as a working river by artists including John Constable, Thomas Gainsborough, Alfred Munnings, John Nash and Cedric Morris. Constable's connection with the area was especially important, evident in such works as Stour Valley and Dedham Church c. 1815. John Nash, who was an official war artist, settled in the Stour valley and is buried at St Andrew's at Wormingford, one of its typically serene small settlements.
Dark skies The low population densities and distance from large cities means much of the Stour valley has relatively little light pollution, an situation which is unusual in the densely populated south-east of England. As a consequence, the hamlet of Thorington Street has been designated an International Darksky Community.Dedham Vale National Landscape website - https://dedhamvale-nl.org.uk/2026/02/17/dedham-vale-home-to-designated-international-darksky-community/
Biodiversity RSPB Stour Estuary is a nature reserve managed by the Royal Society for the Protection of Birds (RSPB). It is located on the south bank of the estuary, to the east of Wrabness. Just to the west is Wrabness Nature Reserve, a Site of Special Scientific Interest covering . It is run by the Essex Wildlife Trust and is also a designated Local Nature Reserve and a Local Wildlife Site.
Environmental harms In July 2019 sections of the river ran dry because of low rainfall and debris blocking flows at Bures Mill. The Environment Agency pumped water from boreholes into the river in an attempt to restore water levels.
Navigation
There are no known records detailing use of the river by boats prior to the 17th century, but in 1634, Daniel Biatt, the mayor of Sudbury, met with Mr Doctor Warren and Mr Spencer to plan how to make the river navigable. On 11 December 1638 Spencer obtained letters patent authorising him to make the river navigable from Manningtree to Sudbury. No progress was made, due to unrest around the time of the civil war, Spencer's pre-occupation with a similar project on the River Ouse, and his own financial difficulties. A similar scheme was proposed by Mr Maynard in 1658, but again no progress was made. By the late 1600s, John Little and Benjamin Dodd had obtained the rights of the Letters Patent, and later claimed they had spent a lot of money improving the river.
What they did is unknown, for in 1703 the mayor and corporation of Sudbury presented a bill to Parliament to make the river navigable. Little and Dodd objected, as they already had rights under the letters patent, but their case was dismissed, and an act of Parliament, the (4 & 5 Ann. c. 2), was granted to Sudbury on 16 February 1706. It was entitled An Act for making the River Stower navigable from the town of Manningtree, in the county of Essex, to the town of Sudbury, in the county of Suffolk. A long list of commissioners was established, and the work was to be carried out by the mayor and aldermen of Sudbury and ten others. It had to be started before 24 June 1708 and completed by 24 June 1713. In order to placate the millers, they were given rights to carry millstones and building materials for their mills without payment of tolls. A towpath would be provided on parts of the river, but the path was intermittent.
The act also allowed winches and other engines to be set up on the banks, so that boats could be hauled through the flash locks which were built. A total of 13 flash locks and 13 pound locks were constructed. The posts on which the lock gates hung were continued above the top of the lock, and a lintel spanned the lock to prevent the posts collapsing inwards. Timber sides to the locks later replaced the earth walls, and in the 19th century the flash locks were removed, while the pound locks were rebuilt, so that there were 15 between Sudbury and the estuary.