Ouse
View looking north towards Cliffe at high tide from Southease swing bridge
Location
Country	England
Counties	West Sussex, East Sussex
Towns/Cities	Slaugham, Lindfield, Newick, Isfield, Barcombe, Lewes, Newhaven
Physical characteristics
Source
• location	Lower Beeding, West Sussex, UK
• coordinates	51°02′20″N 0°14′04″W / 51.038875°N 0.234315°W / 51.038875; -0.234315
• elevation	85 m (279 ft)
Mouth	English Channel
• location	Newhaven, East Sussex, UK
• coordinates	50°47′03″N 0°03′29″E / 50.784217°N 0.057995°E / 50.784217; 0.057995
• elevation	0 m (0 ft)
Length	35 miles / 56 kilometres

v t e River Ouse, Sussex route map
Legend
Source of the Ouse Slaugham Place Mill Pond  A23  Bridge Ouse Valley Viaduct, Brighton Main Line Former limit of navigation (1812-1861) Upper Ryelands Bridge, Balcombe 19 Riverswood Lock Ardingly Reservoir Ardingly branch line Bridge 18 Ryelands Lock 17 Tester's Lock 16 Fulling Mill Lock Lindfield 15 Pim's Lock 14 East Mascalls Lock 13 Henfield Wood Lock 12 Freshwater Lock 11 Polebay Lock 10 Bacon Wish Lock Bluebell Railway, Sheffield Park Greenwich Meridian  A275  Sheffield Bridge 9 Iron Gate Lock 8 Fletching Lock 7 Goldbridge Lock, Newick  A272  Newick 6 Sharps Bridge Lock Shortbridge Shortbridge Branch 5 Isfield Lock River Uck, Isfield Longford Stream Wealden Line, disused railway Iron River, Isfield Bevern Stream 4 Oil Mill Lock 2-3 Barcombe Mill Locks and weirs Tidal Limit, Barcombe Mills Hamsey weir Wealden Line, disused railway 1 Hamsey Lock, Hamsey Greenwich Meridian  A277  Phoenix Causeway Bridge, Lewes Lewes East Coastway line  A27  Glynde Reach Southease Swing Bridge, South Downs Way Denton Island  A259  Newhaven Swing Bridge Newhaven Port of Newhaven and Marina Newhaven Ferry Terminal Newhaven Fort Mouth of the Ouse, English Channel

The Ouse (/uːz/ OOZ) is a 35 miles (56 kilometres) long river^[1] in the English counties of West and East Sussex. It rises near Lower Beeding in West Sussex, and flows eastwards and then southwards to reach the sea at Newhaven. It skirts Haywards Heath and passes through Lewes. It forms the main spine of an extensive network of smaller streams, of which the River Uck is the main tributary. As it nears the coast it passes through the Lewes and Laughton Levels, an area of flat, low-lying land that borders the river and another tributary, the Glynde Reach. It was a large tidal inlet at the time of the Domesday book in 1086, but over the following centuries, some attempts were made to reclaim some of the valley floor for agriculture, by building embankments, but the drainage was hampered by the buildup of a large shingle bar which formed across the mouth of the river by longshore drift.

In 1539, a new channel for the entrance to the river was cut through the shingle bar, and meadows flourished for a time, but flooding returned and meadows reverted to marshland. The engineer John Smeaton proposed a solution for the drainage of the valley in 1767, but it was only partly implemented. William Jessop surveyed the river in 1788, and produced proposals to canalise the upper river above Lewes, and to radically improve the lower river. The Proprietors of the River Ouse Navigation were created by Act of Parliament in 1790, and eventually built 19 locks, to enable boats to reach Upper Ryelands Bridge at Balcombe. Trustees and the Commissioners of the Lewes and Laughton Levels jointly managed the work on the lower river, and the agriculturalist John Ellman continued the progress while he was Expenditor for the Commissioners, which enabled 120-ton ships to reach Lewes by 1829. Navigation on the upper river could not compete with the railways, and all traffic had ceased by 1868.

On the lower river, Newhaven became an important port and barge traffic continued using the river up to Lewes until the 1950s. Cross-Channel ferries still sail from the port. The river provides habitat for many varieties of fish, including unusually large sea trout that swim up the river to spawn in the higher tributaries. The Lewes Brooks area of the levels is a Site of Special Scientific Interest because of its wide variety of invertebrates. Walkers can follow the course of the river by using the Sussex Ouse Valley Way long-distance footpath, and the Sussex Ouse Conservation Society promotes awareness of the navigation by publishing details of shorter walks. The Sussex Ouse Restoration Trust is hoping to see navigation restored to the upper river, but this is not universally popular, as the Ouse and Adur Rivers Trust is opposed to the idea.

Course

The River Ouse, together with its main tributary the River Uck, form the central spines of a network of streams and rivers^[2] which drain over 250 square miles (650 km²) of Sussex. There are around 750 miles (1,200 km) of streams in total,^[3] of which some 140 miles (230 km) are designated as main rivers, on which the Environment Agency has a responsibility for maintenance.^[4]

The river rises near Lower Beeding in West Sussex and meanders eastwards, passing under Upper Ryelands Bridge, once the limit of navigation. After it has been joined by the outflow from Ardingly Reservoir, created by building a dam across the valley of a tributary, which has resulted in the partial flooding of two river valleys, it turns to the south east, passing to the north of Lindfield and Haywards Heath. It passes into East Sussex just before reaching Sheffield Park railway station on the preserved Bluebell Railway. After skirting around Newick, it turns to the south and is joined by its main tributary, the River Uck, flowing in from the north east, before reaching Isfield.^[5] Most of the tributaries are in the upper catchment that have joined it originate in the heaths and forests of the High Weald, where fast-flowing small streams cut deep valleys through woods, and flow over underlying beds of sandstones and clays.^[4]

Below Isfield, the narrow valley widens out into a broad flood plain, and the river is joined by the Longford Stream, the Iron River and the Bevern Stream, before it reaches Barcombe Mills.^[5] There is a network of channels at Barcombe, which once supplied water for at least two watermills, but the last one was destroyed by fire in 1938.^[6] On the east bank of the river is Barcombe Reservoir and Water Treatment Works. Both are owned by South East Water, who extract water from the river and depending on the quality of the water, store it in the reservoir or treat it immediately and pump it into the public water supply. The works was constructed in two stages, in 1962 and 1977 and can deliver up to 75 Megalitres per day (Mld) for public consumption.^[7] Just north of this on the west bank of the river is the Anchor Inn, dating from 1790, which has boats for hire, restaurants and bars, and is licensed for civil weddings.^[8]

Some of the tributaries on this middle section are similar to those on the upper section, but others are lowland streams, where the underlying geology is alluvium and clays, and which flow more slowly. The Bevern Stream and Northend Stream both originate in the chalk uplands of the South Downs, but traverse greensand and clay before they reach the Ouse.^[4] Below the weirs of Barcombe, the river is partially tidal, and forms large meanders, with numerous ox-bow lakes. At Hamsey, a long lock cut crosses the neck of a large meander creating Hamsey Island,^[5] home to St Peter's Church, which is situated on a mount. Much of it dates from the 12th century, with 14th and 15th century additions, and the structure is Grade I listed.^[9] Flow on the river above is modulated by a half-weir,^[4] which prevented a serious ecological disaster spreading further downstream, when a spillage of pesticide near Newick in 2001 killed the insect populations and more than 500 fish on a 12-mile (20 km) stretch of the river.^[10]

The tidal river continues through the town of Lewes, where the channel has been considerably modified over time, and is crossed by three bridges. Willey's Bridge is a small footbridge opened in 1965, to provide public access to South Malling church and to enable residents in housing estates built at Malling to get to Lewes. Previously, access to the church had only been available on Sundays, when owners of Malling Deanery allowed people to use their private suspension bridge, constructed in 1934, and located a little further upstream. This had in turn replaced a wooden bridge erected in 1868.^[11] The Phoenix Causeway is a larger road bridge named after the former Phoenix Ironworks, which was constructed in 1979 to provide a bypass for Cliffe High Street,^[12] and the Grade II listed Cliffe Bridge carries the High Street over the river. It was designed by Nicholas Dubois, and built in 1726–27. It consists of a single arch in red brick with stone dressings, but the original design has been modified. An inscribed keystone was obscured when a footway was added to the north side of the bridge in 1888, and cast iron balustrades replaced the original brick balustrades when the bridge was reconstructed in 1932.^[13] After Cliffe the Winterbourne stream flows into the Ouse and also supplies water to the Railway Land nature reserve, owned by Lewes District Council, and managed with help from the Railway Land Wildlife Trust. It covers 25 acres (10 ha) and was the site of railway sidings until 1989. It includes a reed bed called the Heart of Reeds.^[14] The Ouse continues southeast past Glynde, where the tributary of Glynde Reach joins from the east, and then passes Rodmell, Southease and Piddinghoe. There are public pathways on both sides of the channel for most of this stretch.^[5]

At Southease there is a swing bridge, designed by Henry E Wallis of Westminster in 1878 and installed two years later, to replace a previous structure slightly further upstream. It consists of three bowspring arches, one fixed and the other two mounted on a central pivot. It was manually operated by a capstan mounted on the movable section, and is a rare example of its type, which are more normally found in docks and industrial areas. In 1988, Parliamentary approval was obtained to fix the bridge in position,^[15] as it had not been opened since 1967.^[16] The river finally reaches Newhaven, where it splits industrial Denton Island from the mainland. A wooden drawbridge was built in 1794 to carry the coastal road over the river, but this was replaced in 1866, when a cast iron swing bridge was erected in its place. It carried both a road and a tramway, which was used in the construction of the West Quay breakwater, a project which was finally completed in 1889. The tramway was then used to facilitate maintenance of the breakwater, until the tracks were lifted in 1963. A new road bridge, at a higher level and slightly further to the north, replaced the swing bridge in 1974.^[16] It is opened regularly for commercial shipping, near to high tide, but as the bridge carries the A259 road, each opening causes significant traffic congestion.^[17] Below the bridge, the river becomes the Port of Newhaven, where there is a ferry terminal for sailings to Dieppe in France, a service which has been running since 1847.^[18] Finally, the river flows into the English Channel, surrounded on either side by two long breakwater piers.^[5]

Name

'Ouse' is a common name for rivers in England, with examples including the Ouse in Yorkshire, and the Great Ouse and Little Ouse in Norfolk, Suffolk and Cambridgeshire. The name may stem from the Celtic word Ūsa, which is in turn derived from the word *udso-, meaning "water". The root of this word is the Indo-European *wed-, from which the modern English words "wet" and "water" also stem. If this derivation is correct, then its name is a tautology, meaning "Water river" or "Wet river".^[19] However, the National Rivers Authority stated that the river above Lewes was called the Middewinde historically, while the river from Lewes to the sea was called "The Great River of Lewes", and that the present name is a contraction of Lewes, with which it rhymes.^[20] This claim is also supported by others.^[21]

Formation

The Ouse is one of the four rivers that cut through the South Downs. It is presumed that its valley was cut during a glacial period, since it forms the remnant of a much larger river system that once flowed onto the floor of what is now the English Channel. In the warmer interglacials the lower valley would have flooded; there are raised beaches 40 metres (Goodwood-Slindon) and 8 metres (Brighton-Norton) above present sea level. The offshore topography indicates that the current coastline was also the coastline before the final deglaciation, and therefore the mouth of the Ouse has long been at its present latitude.^[22]

Inundation and drainage

When the Domesday book was produced in 1086, the Ouse valley was probably a tidal inlet with a string of settlements located at its margins.^[23] In later centuries the river was draining the valley sufficiently well for some of the marshland to be reclaimed, by building embankments to create highly prized meadow land.^[24] However, by the 14th century the Ouse valley was regularly flooding in winter, and frequently the waters remained on the lower meadows through the summer. In 1422 a Commission of Sewers was appointed to restore the banks and drainage between the coast and Fletching, around 20 miles (32 km) inland, which may indicate that the Ouse was affected by the same storm that devastated the Netherlands in the St Elizabeth's flood of 1421. Drainage became so bad that 400 acres (1.6 km²) of the Archbishop of Canterbury's meadow at Southerham were converted into a permanent fishery (the Brodewater) in the mid-15th century, and by the 1530s the entire Lewes and Laughton Levels comprising over 6,000 acres (24 km²), were reduced to marshland again.^[25]

Part of the problem of flooding was caused by longshore drift creating a huge shingle bar across the river mouth, which had gradually moved eastwards to Seaford, some 2 miles (3.2 km) from its position in Roman times. The bar prevented the river from draining effectively, and made it difficult for ships to enter the estuary.^[26] Prior Crowham of Lewes Priory sailed to Flanders and returned with two drainage experts. In 1537 a water-rate was levied on all lands on the Levels to fund the cutting of a channel through the shingle bar at the mouth of the Ouse, below Castle Hill at Meeching, to allow the river to drain the Levels. This canalisation created access to a sheltered harbour, Newhaven, which succeeded Seaford as the port at the mouth of the Ouse.^[27]

The new channel was completed by 1539^[28] and drained the Levels so that much of the valley floor could be reclaimed for pasture. However, shingle continued to accumulate and so the mouth of the Ouse began to migrate eastwards again. In 1648 the Ouse was reported to be unfit either to drain the levels or for navigation.^[29] At some time between 1676 and the publication of an Admiralty chart in 1698, the river flowed along the back of the shingle bar and broke through into the sea about 0.5 miles (0.8 km) further to the east, at the site of a tide mill.^[30] The outlet at Newhaven had been reinstated by 1731,^[31] when the Newhaven Harour Commissioners were established by Act of Parliament. The engineer John Reynolds carried out some work for them on the piers at the entrance to the river, and constructed a sluice across it at Piddinghoe between 1731 and 1733, working for the Drainage Commissioners, but that was short lived, as it was damaged in 1736 and taken down rather than repaired.^[32] By the 18th century the valley was regularly inundated in winter and often flooded in summer.^[22]

Smeaton's survey

In 1767 the Commissioners for the Lewes and Laughton Levels employed the engineer John Smeaton to survey the river and the drainage of the levels, which he did over four days in June following a period of wet weather. He found that the meadows, which were locally known as brooks, were in many cases under water, but that their condition, and therefore the remedies that would be required, were variable. In particular, the brooks of Southover, Iford, Pool Bar, and Rodmell, which he called the West Levels, were badly affected as their embankments were low and poorly maintained. At high tide, the level of the river was above that in the meadows. The same applied to Ranscombe brooks, to the north of the junction between the Ouse and the Glynde, Further down river, at White Wall and Tarring, the brooks were generally dry, which he attributed to the land surface being higher, the walls being higher and well maintained, and the outfall sluices from the meadows being arranged at a lower level in relation to the river.^[33]

He noted that the rise and fall of the tide below Piddinghoe was some 8 feet (2.4 m), but this was reduced to just 6 inches (15 cm) at the mouth of the Glynde, and was barely visible at Lewes Bridge. A series of shoals, combined with the narrow and winding channel, held water back and prevented it from draining from the levels. He also commented on the great shingle bar crossing the mouth of the river at Newhaven, which if removed would allow the water levels to be around 6.5 feet (2.0 m) lower at low tide.^[34] The brooks above Lewes Bridge became gradually drier as he progressed towards Barcombe Mill, but with almost no fall on the river, its winding course and numerous shoals hampered the drainage of the meadows. The brooks bordering the Glynde, to the east of Ranscombe, were generally at a higher level, but were affected by stagnant water lying on the surface. There was again no gradient on that river, which followed a winding course, but he was confident that if the drainage of Ranscombe could be solved, the drainage of the Laughton Levels would also be.^[35]

His first proposal to achieve the drainage of the levels was to straighten the river, to remove all of the obstructions, and to construct an outfall sluice, to prevent the tides entering the river. The brooks on the west level and at Ranscombe would need better embankments, and adequate sluices to allow water to drain away when required. A second option involved raising the banks on all of the meadows, and constructing a separate sewer to carry surplus water from them to the sea, leaving the main river largely unaltered.^[36] The outfall sluice would have been located at Tarring Tenantry near Piddinghoe, and would contain three openings, two of 13 feet (4.0 m), each with a set of pointed doors facing in opposite directions, to prevent the sea entering the river, and to retain water in the river during dry periods. The third opening would be 14 feet (4.3 m) wide, with double pointed doors facing in both directions, so that it could additionally be used as a navigation lock at all states of the tide and river.^[37] He estimated the cost of the first scheme to be £10,800,^[38] and the Commissioners implemented some of his suggestions, improving the channels below Lewes in 1768, by dredging to remove shoals and making the channel wider in places. However, they did little to straighten the river, and Smeaton's great sluice was not constructed.^[39]

Ouse navigation

Zdroj:https://en.wikipedia.org?pojem=River_Ouse,_Sussex
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