The River Rother flows for through the English counties of East Sussex and Kent. Its source is near Rotherfield in East Sussex, and its mouth is on Rye Bay, part of the English Channel. Prior to 1287, its mouth was further to the east at New Romney, but it changed its course after a great storm blocked its exit to the sea. It was known as the Limen until the sixteenth century. For the final , the river bed is below the high tide level, and Scots Float Sluice is used to control levels. It prevents salt water entering the river system at high tides, and retains water in the river during the summer months to ensure the health of the surrounding marsh habitat. Below the sluice, the river is tidal for .
The river has been used for navigation since Roman times, and is still navigable by small boats as far as Bodiam Castle. It flowed in a loop around the northern edge of the Isle of Oxney until 1635, when it was diverted along the southern edge. Scots Float Sluice was built before 1723, when the engineer John Reynolds made repairs to it, and later extended it, to try to keep the channel clear of silting, but it was criticised by John Rennie in 1804, as it was inconvenient to shipping. The river became part of a defensive line to protect England from the threat of invasion by the French in the early 1800s, when its lower section and part of the River Brede formed a link between the two halves of the Royal Military Canal. Scots Float Sluice was again rebuilt in 1844. Some of the valley were inundated by floodwater in 1960, which resulted in the Rother Area Drainage Improvement Scheme being implemented between 1966 and 1980. The river banks were raised, and 20 pumping stations were installed.
The river has been managed by a number of bodies, including the Rother Levels Commissioners of Sewers, the Rye Harbour Commissioners, and the Board of Conservators for the River Rother. After the passing of the Land Drainage Act 1930, it was managed by the Rother and Jury's Gut Catchment Board, the Kent River Board, the Kent and Sussex River Authorities, the National Rivers Authority and finally the Environment Agency. It is unusual, in that while it is under the jurisdiction of the Environment Agency, it has been a free river since 1826, and so no licence is required to use it. Management of the levels adjacent to the river is undertaken by the Romney Marshes Area Internal Drainage Board. The Rother passes by or near the villages of Etchingham, Robertsbridge, Bodiam, Northiam, and Wittersham.
Etymology The modern name of the river is comparatively recent, probably dating from around the sixteenth century. It is derived from the village and hundred of Rotherfield, located where the river rises. The name Rotherfield is possibly derived from the Old English Hrytheran-felda, meaning 'open land of the cattle'. Prior to being called the Rother, it was known as the Limen throughout its length. This is a Celtic word meaning 'river'. In several Anglo-Saxon charters, it is suffixed with -ea, appearing as Limenea, where the suffix also means 'river', but in Old English. In the Anglo-Saxon Chronicle it is called the River Lympne or Lymne. During the thirteenth century, it was known as the River of Newenden.
Hydrology The Rother rises in the High Weald of Sussex, at around above ordnance datum (AOD), and descends rapidly. It is joined by the River Dudwell at Etchingham and the River Darwell at Robertsbridge, and by the time it reaches Udiam, it is only AOD. Average annual rainfall in the High Weald is , and most of the underlying geology is impermeable, resulting in rain rapidly reaching the river and flowing down to the sea. The river valley is thus prone to winter floods, while during the summer months, the flow can be quite low in dry periods, as there are few groundwater aquifers. Between Udiam and Bodiam, the bed of the river drops below sea level, and the lower river flows slowly. The surrounding land is crossed by networks of canals and ditches, which are pumped into the river during the winter to drain the land. During the summer, water is transferred in the other direction, to manage the habitat of the marshland.
Scots Float sluice, some from the mouth of the river, is used to control levels. It is named after Sir John Scot(t), who enlarged a harbour on the site around 1480. The river below it is tidal, and it is closed as the tide rises, to prevent salt water passing up the river. During dry years, the sluice may be kept closed for most of the summer, as the water is used to maintain the marsh environment. A navigation lock bypasses the sluice. If heavy rainfall coincides with a high tide, where outflow is tide-locked, the river above the sluice to Bodiam acts as a huge holding reservoir for flood water, and is managed as such. In times of high flow, water is also pumped from the river at Robertsbridge into Darwell Reservoir, which can hold 167 million cubic feet (4730 Ml) of water. It covers an area of and was built between 1937 and 1949. Since the 1980s, its output has been taken by pipeline to Beauport Park, from where it provides a public water supply for Hastings.
History Near its mouth, the River Rother no longer follows its ancient course, as it once flowed across Romney Marsh and joined the sea at Dungeness.Christopher Green, 1988, Paleography of Marine Inlets in the Romney Marsh Area, PDFMartin Wass, 1993, A Possible Northern Course of the Rother (Sections across the buried canal), PDF It is widely asserted that in 1287 a hurricane, known as the Great Storm, caused large quantities of shingle and mud to be deposited on the port of Romney and the mouth of the river. The water from the river created a new channel, joining the River Brede and the River Tillingham near Rye, where the combined rivers flow into the sea. However, Tatton-Brown has argued that patterns of occupation on Romney Marsh suggest that the change of route took place at least a century before that date. Rye became part of the Cinque Ports in the thirteenth century, and although it is situated some distance from the sea, its harbour is still visited by commercial shipping and has a fleet of fishing boats.
Early developments
The river is known to have been used for shipping in Roman times, when it was navigable to Bodiam and possibly further upstream. There are records of small boats reaching Etchingham during Saxon and Norman periods. Stone for building Bodiam Castle was transported along the river in the fourteenth century, and iron was shipped from Newenden or Udiam in the sixteenth century. A century later, an iron store was erected at Udiam. Maytham Wharf served Rolvenden, while Tenterden was served by Small Hythe.
The Isle of Oxney is an area of higher land to the west of Appledore, which is isolated from high ground to its north and south. The valley around the northern edge of it was known as the Upper Levels, while that to the south was called the Wittersham Levels, and had its own Commission of Sewers. The Rother had been routed around the northern side of the Isle since the 1330s, when the Knelle Dam () was built at the western end of the Wittersham Levels. The sea was prevented from entering the levels by the Wittersham Sea Wall, built across the eastern end of the valley. This enabled some of the levels to be used for agriculture all year round, although some was only suitable for summer grazing. A perennial problem with the river was that the tides deposited large quantities of silt in the channel, and during the summer months the flow of the river was insufficient to scour the silt away. As a result, some of the Upper Levels were "drowned lands" by 1629, meaning that they were persistently flooded, and another were only usable in the summer months.
From the 1600s onwards, much effort and expense had been spent trying to drain the Upper Levels, including the construction of the Great Freshwater Sluice below Appledore. Its purpose was to limit the inflow of the tide, and to control the outflow of the river. The works were not particularly successful, and negotiations were started with the Commissioners of the Wittersham Levels to divert the river through those levels. After initial reluctance, an agreement was reached in February 1631. The western end of the levels, from Kent Wall to the Knelle Dam, was to be used as an "indraught", essentially a holding reservoir for river water and some sea water, which would be released in a controlled way to scour the main channel. An embanked channel called the New Salt Channel was constructed across the levels between Kent Wall and a new sluice in the Wittersham Sea Wall. The river was flowing to the south of the Isle by 4 May 1635, an on 4 October, the navigation was also routed along the new channel, reducing its length by . The former channel to the north became known as the Reading Sewer.
Disaster occurred on Lady Day 1644, when an exceptionally high tide flooded the Upper Levels, and broke through the walls of the New Salt Channel. The Commissioners authorised the construction of a new sea sluice at Kent Wall, and work began in May 1646, but in September, they decided that it should be built at Blackwall instead. The height of Knelle Dam was regularly adjusted, in an attempt to manage the amount of water that still flowed along the Appledore Channel, and the conflicting needs of navigation and drainage. The Great Freshwater Sluice below Appledore deteriorated, and failed in 1650. A new sluice with three channels was built in 1669. The financial burden on the Upper Levels as a result of the sea entering the Wittersham Levels was huge, as they had to pay rent on all land that was not available to its original owners, and so in 1671, an agreement was reached that the sea would be excluded from the levels. Work began in 1680 to enclose areas of land on both sides of the valley, and was largely completed by 1684. The work included a new embanked channel for the Rother, which was built along the southern edge of the valley. It was called the Craven Channel, and ended at Craven Sluices.
When repairs to Craven Sluices were necessary in 1684, the water was temporarily diverted into Scots Float Channel. This worked well, and a regulating penn was built, so that water could be routed to Craven Sluices or Scots Float. Knock Sluice was built below the Appledore Sluice in 1686, and land above it was reclaimed. In 1696, New Knock Sluice was built, close to Craven Sluices, and the sea was finally excluded from the Wittersham Levels.
In 1723, the Commissioners of the Kent and Sussex Rother Levels employed the civil engineering contractor John Reynolds to make repairs to Scots Float Sluice, a timber lock on the lower river. He built a dovetailed sheet pile wall below the foundations, and the Commissioners offered him the job of maintaining the levels in 1725, for which he would be paid £65 per year. He moved to Iden and held the post for fourteen years. Silting of the river estuary caused mounting problems with the drainage of the levels during the 1720s. Reynolds carried out further work on the sluice in 1729, and in 1732 reconstructed it to provide an extra outlet. Several new channels were excavated through the levels in the early 1730s, so that all the runoff passed through Scots Float. Reynolds resigned his post in 1739 as he was too busy with other engineering projects.
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