River Idle facts for kids
Quick facts for kids River Idle |
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The road bridge and sluice gate at the junction with the River Trent
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Country | England |
Physical characteristics | |
Main source | Confluence of River Maun and River Meden 59 feet (18 m) |
River mouth | River Trent 0 ft (0 m) |
Length | 26 miles (42 km) |
Basin features | |
Tributaries |
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The River Idle is a river in Nottinghamshire, England. Its source is the confluence of the River Maun and River Meden, near Markham Moor. From there, it flows north through Retford and Bawtry before entering the River Trent at Stockwith near Misterton. The county boundary with South Yorkshire follows the river for a short distance near Bawtry, and the border with Lincolnshire does the same at Idle Stop. Originally, it flowed northwards from Idle Stop to meet the River Don on Hatfield Chase, but was diverted eastwards by drainage engineers in 1628.
Most of the land surrounding the river is a broad flood plain. Between Retford and Bawtry, the floodplain is partly occupied by a number of sand and gravel pits, where exhausted forming public lakes for fishing, while beyond Bawtry, the river is constrained by high flood banks, to allow the low-lying areas to be drained for agriculture. Its main tributaries are the River Poulter and the River Ryton.
The river is navigable to Bawtry, and there is a statutory right of navigation as far upstream as East Retford, although access to the river through the entrance sluices is very expensive. Its drainage functions are managed by the Environment Agency, but there is no navigation authority. The river is important for conservation, with the Idle Washlands and some of the sand and gravel pits of the Idle Valley being designated Sites of Special Scientific Interest.
Contents
Hydrology
To the west of the region through which the river flows, the underlying geology is an extensive water-bearing porous rock structure called the Magnesian Limestone aquifer. Magnesian limestone is so named because if contains quantities of the mineral Dolomite, which is rich in Magnesium. Further to the east, this rock is covered by another layer of porous rock called the Triassic Sherwood Sandstone aquifer, which is the major geological component of the area. Continuing eastwards, both are then covered by a layer of Mercia mudstone. Where these aquifers reach the surface, they often supply water to the river system, but can also take water from it. This is affected by the extraction of groundwater, particularly for public water supply, and by fracturing of the aquifers as a result of subsidence caused by deep coal mining.
The catchment for the River Idle covers some 280 square miles (725 km2), which has an average annual rainfall of 24.3 inches (620 mm) (based on figures from 1961 to 1990). About a third of this finds its way into the rivers. Water quality is moderate. The Environment Agency use a six-stage rating scale, from 'A' to 'F', called the General Quality Assessment, to classify rivers. 'A' on the GQA is the best quality of water, while 'F' is the poorest. Factors which affect the quality are levels of ammonia, levels of dissolved oxygen and the Biochemical oxygen demand (BOD), which measures the amount of dissolved oxygen needed by organisms to break down organic matter in the water. These factors are generally worse when the water is discharged from sewage treatment processes, and tend to be worse in summer, when such discharges make up a greater proportion of the total flow in the river. The tributaries of the Idle are rated at 'C' on the GQA scale, because they pass through urban areas, and there are significant discharges to the rivers from sewage treatment works. The average flow in the River Maun is around 13 Mld (megalitres per day) in dry weather, which is supplemented by Mansfield sewage treatment works, which discharges nearly 23 Mld. Water quality does not improve in the Idle, and remains at 'C' on the GQA scale all the way to the Trent. The Environment Agency maintain gauging stations to measure the flow in the river near the junction with the River Poulter, and to the east of Mattersey.
History
The 7th century Battle of the River Idle, in which King Rædwald of East Anglia and his forces defeated the Northumbrians, is described in the 12th century Historia Anglorum, written by Henry of Huntingdon. Until the 17th century, the river flowed northwards from a place which subsequently became known as 'Idle Stop', across Hatfield Chase. To the west of Wroot, the River Torne formed two channels, both of which joined the Idle to the east of Wroot, and the Idle continued to join the River Don to the north west of Sandtoft. From Dirtness, the Don flowed to the north east, to Adlingfleet, where it joined the River Trent near to its confluence with the River Ouse. However, in 1626 the Dutch drainage engineer Cornelius Vermuyden was appointed by King Charles I to drain Hatfield Chase. Vermuyden brought over a number of Walloon partners, known as the Participants, who took shares and performed the drainage work, which was completed two years later. The Idle was affected by this work. Its course was blocked by a dam constructed at Idle Stop, and its waters were diverted along the Bycarrs Dyke, a Roman navigation channel, which joined the River Trent at West Stockwith. In order to isolate the river from Hatfield Chase, a barrier bank was constructed along the northern edge of this channel, for 5 miles (8 km) from the dam to Stockwith. A navigable sluice was built about 1 mile (1.6 km) from the river mouth at Misterton Soss by Vermuyden's nephew, John Liens, between 1629 and 1630, to prevent water from the Trent flooding the land to the south of Bycarrs Dike. The construction was of timber, with high banks running to the Trent on both sides of the channel. Lifting gates gave access to a lock chamber 60 by 18 feet (18.3 by 5.5 m), which could be used when the Trent was not in flood. Liens was compelled to carry out the work by the Court of Sewers, to prevent the flooding of Misterton and Haxey Commons.
A drainage channel called the New Idle River was constructed in a straight line from Idle Stop to Dirtness, crossing the Torne by a tunnel at Tunnel Pits, about halfway along its course. From Dirtness, it was routed to the east to Hirst, where it was joined by the new course of the Torne, and the two channels ran parallel to an outfall at Althorpe on the Trent. There was a great deal of dissatisfaction with the drainage scheme, which resulted in claims and counter-claims in the courts. A petition brought to the Privy Council by several local authorities from Nottinghamshire, alleging that the Participants had caused damage, was judged in their favour. The Commission of Sewers decided that a new cut was needed, to carry water from Misterton, Gringley and Everton to the Trent, and so relieve the Idle, but only about 1.2 miles (2 km) was constructed before landowners objected and the work was not completed. During the English civil war, much of the scheme was damaged. The Participants supported the King, while commoners on the Isle of Axholme supported the Parliamentarians. Alleging that the Royalists would invade Axholme from the south, they broke down Misterton sluice and the Snow Sewer flood gates in 1642 or 1643, causing widespread flooding and damage estimated at £20,000. The Sheriff of Lincoln repaired both structures, but a band of 400 villagers destroyed them again. Legal action and rioting continued for some years. Nathaniel Reading, acting for the Participants, raised an 'army' in 1656, and fought a total of 31 pitched battles, including several against the men of Misterton and Gringley. It was not until 1719 that the issues were finally settled and peace returned to the area.
Daniel Defoe visited the river in the early 18th century, and described it as full and quick, though not rapid and unsafe ... with a deep channel, which carries hoys, lighters, barges or flat-bottom'd vessels. He went on to describe the port of Bawtry, which was the limit of navigation, as famous all over the south part of the West Riding of Yorkshire, for it is the place wither all their heavy goods are carried. Traffic included lead from Derbyshire, brought to Bawtry by pack horse, Swedish iron bound for Sheffield, cutlery from Sheffield, iron products from furnaces in Nottinghamshire and Derbyshire, together with coal and timber.
In 1720, the merchants of East Retford obtained an Act of Parliament to allow them to extend the navigation to Retford, and to charge tolls. Although no work appears to have been carried out, the plans were still being considered in 1757, by which time much of the river's trade had been lost, the Derbyshire lead trade now using an improved River Derwent, and the Sheffield trade using the River Don Navigation.
Boats navigating to Bawtry were shallow-drafted, and were approximately 48 by 14 feet (14.6 by 4.3 m), capable of carrying between 12 and 24 tons. Trade in 1767 amounted to 4,415 tons, but the opening of the Chesterfield Canal in 1777 provided a more convenient outlet for most goods, and by 1828 commercial traffic had ceased to use the river. There was a wharf at Bawtry, but a large bend just above it was in the way when the Great Northern Railway was constructed. The Railway Company constructed a new cut for the river, but the channel to the wharf soon silted up.
Management
The river below Idle Stop and the maintenance of the sluice at Misterton Soss remained the responsibility of the Hatfield Chase Company from the time of Vermuyden's agreement with Charles I until 1930, when the management of low-lying areas was addressed by the Land Drainage Act 1930. Initially control passed to the newly formed Trent River Catchment Board, who built the Trent/Idle sluice across the mouth of the Idle, next to the road bridge. It consisted of a single guillotine gate. The catchment board was superseded by the Trent River Board, under the provisions of the River Boards Act 1948. They carried out some dredging of the river, and maintained the river level some 8 feet (2.4 m) above ordnance datum. In 1963, the sluice at Misterton Soss was abandoned. The south wall and floor of the lock were removed, and the river level was allowed to run down to the level of low water in the Trent, making navigation difficult.
It has been stated that navigation rights on the river ceased with the passing of the Trent River Authority (General Powers) Act of 1972, but the situation is a little more complex. The Trent River Authority intended to remove navigation rights in their Act, but met with opposition from the Inland Waterways Association (IWA) and Retford & Worksop Boat Club, with additional support from Nottinghamshire County Council, East Retford District Council, Doncaster Rural District Council and the Labour Member of Parliament Nigel Spearing. In the face of such opposition, the clause to remove navigation rights was removed, although the Act did contain proposals for unspecified drainage works which might "interfere with or obstruct the right of navigation." They subsequently proposed building two fixed weed screens across the river, and replacing the final section of river by a pumping station with culverts into the Trent. The IWA continued to negotiate, and an agreement was reached that the weed screens would not block the entire channel. Because the pumping station was thought to be essential, the Trent River Authority agreed to provide a slipway for trailable boats, which was later built near Haxey Gate Bridge.
On 2 December 1971, the government outlined proposals to replace the existing river authorities with water authorities, as part of what would become the Water Act 1973. There would be a new responsibility on such authorities, who would "be placed under an obligation when constructing major works to develop amenities and assist the provision of facilities..." The immediate plans for the pumping station were shelved. Meanwhile, Retford & Worksop Boat Club organised two cruises of the river in 1972, one in April when ten boats reached Bawtry, and one in October, when 15 boats entered the river, but could not pass shallows at Misson. Such cruises became an annual event, and 18 or 19 boats reached Bawtry in 1975, with one continuing on to Mattersey. The boat club thus represented boating interests when the new Severn Trent Water Authority revived plans for a pumping station, and the solution adopted was to provide a second sluice nearer to Misterton Soss, which would allow the river to discharge by gravity for most of the time, with the pumps only being operated under extreme flood conditions.
The pumping station and second sluice were built in 1981, some 300 yards (270 m) west of the entrance sluice. Both sluice gates can be raised to the same level as the underside of Haxey Gate Bridge, and the cills are at river bed level. The river level was then maintained at 6 feet (1.8 m) above ordnance datum, and the river was dredged to provide at least 5 feet (1.5 m) of water up to Bawtry. This resulted in significantly less weed growing, which had previously hindered summer cruises.
With the passing of the Water Act 1989 responsibility for rivers, including the Idle, passed to the National Rivers Authority. Their Recreation Officer stated in 1990 that there was no public right of navigation on the Idle, although the Retford and Worksop Boat Club were allowed to cruise on it once a year. A request to allow other boat clubs to use it was subsequently accepted. The National Rivers Authority was replaced by the Environment Agency in 1996, who issued a statement regarding navigation. This acknowledged that there was a common law right of navigation from the Trent to Bawtry, and along the River Ryton as far as Blyth. It also stated that there was a statutory right of navigation from Bawtry to East Retford, as a result of the Act of Parliament obtained in 1720, even though the improvement works on that section of the river were never carried out. As well as requiring 48 hours notice to enter or leave the river, the Environment Agency imposed prohibitive charges to pass through the sluice gates in 2011. These were set at £185 for each transit, and effectively meant that boats could only afford to enter the river in convoys. It has been argued that this way of restricting navigation on a river is legally questionable, although the charges have not been challenged in court. In particular, a legal case from 1702 (The King v Clark) stated that the taking of money to let people pass on a navigable river was against Magna Carta clause 23, which could only be negated by an Act specifically granting such a right.
Although the Environment Agency maintains the river, it is not the navigation authority for the Idle, as the river does not have one. There has been some speculation as to what the position would be if the Canal and River Trust became the navigation authority for Environment Agency waters, a move that has been proposed but not yet implemented. The Environment Agency have also suggested that the river outfall might be reverted to gravity drainage, by leaving the pumping station sluice open and routinely opening the final sluice at low tide. Newman has suggested that access to the river could be significantly enhanced by the construction of a 440-yard (400 m) channel between the river and the Chesterfield Canal at West Stockwith, which would avoid the need for boats to navigate through the sluices, and effectively separate the drainage and navigation functions of the river mouth.
Drainage
The banks of the river below Bawtry have been raised so that the river acts as a high level carrier for the drainage of the surrounding land. The area between the river and the Chesterfield Canal to the south and the Warping Drain to the north is drained by a network of drainage ditches, which are connected to the river by a number of sluices and pumping stations. Water is pumped from the ditches to avoid flooding of the agricultural land, although the pumping station at Gringley can operate in reverse, supplying water to the ditches for irrigation when required. The outflow into the River Trent is controlled by a pumping station and two sluices. A vertical sluice gate protects the entrance to the Idle, and the pumping station and another sluice are situated further back. When the water level in the Trent is low, the sluice gates allow water to leave the Idle by gravity, but at high tide, four electric pumps are used to pump the outflow into the space between the sluice gates until it can again discharge by gravity. The pumping station was commissioned in 1981, and was the largest all-electric pumping station in Britain at the time. When all four pumps are operating, it can discharge 2,124 tons per minute (3,059 Mld).
A large drainage ditch called the Mother Drain runs parallel to the lower river for the final 10 miles (16 km). This was constructed between 1796 and 1801 by the engineer Thomas Dyson, to collect water from the low-lying land to the south of the river. Vermuyden's single sluice was replaced by a triple sluice at this time. The Mother Drain was pumped into the river by two pumping stations at Misterton Soss, the first example of steam engines being used for land drainage outside of the Fens. The first station, called Kate, was built in 1828 and used a 40 horsepower (30 kW) beam engine to drive a 34-foot (10 m) scoop wheel. The wheel was replaced by a centrifugal pump in 1890, and the beam engine was replaced by a 135-horsepower (101 kW) twin cylinder steam engine in 1895. The second, called Ada, was built in 1839, and another 34-foot (10 m) scoop wheel was powered by a beam engine supplied by Booth & Co, who were based at Park Ironworks in Sheffield. Both became redundant in 1941, when the drainage system was re-organised to feed excess water to a new pumping station at Gringley, containing two Ruston diesel engines driving Gwynnes Limited pumps. By 1910, there was a bridge at this point which included tide gates, similar to the V-gates of a lock, which were designed to shut as the level in the River Trent rose. Both the north and the south pumping station are Grade II* listed buildings, and the south building carries an inscribed stone stating "These works erected 1828, Francis Raynes, George Kelk, William Gauntley (Commissioners), Alfred Smith, Engineer". They have been saved from dereliction by being converted to residences, their function performed by the modern electric pumping station at Gringley, while the tide gates have been replaced by the vertical sluice at the entrance to the river.
The low-lying region to the south of the Mother Drain was managed by the Everton Internal Drainage Board, who maintained around 34 miles (55 km) of watercourses. The Board was formally established in 1945, but was the successor to a similar body established in 1796 during the reign of King George III. The watercourses in this area are pumped to the river at Gringley and Scaftworth. The Gringley pumping station was fitted with new diesel pumps in the 1940s, and was upgraded again in 2005 when electric pumps and an automatic weedscreen cleaner were installed.
On the north side of the river, drainage was managed by the Finningley Internal Drainage Board, who were responsible for the maintenance of 24.7 miles (39.8 km) of drains and ditches, which fed surplus water to four pumping stations. Langholme, which is just above Haxey Gate bridge, and Idle Stop pumping stations are situated on the banks of the Idle, while Newington pumping station is set further back on the Austerfield Drain. The fourth pumping station is at Park Drain, on the northern edge of the IDB area, and feeds into the Warping Drain, which joins the River Trent at Owston Ferry. Since April 2012, the pumping stations have been managed by the much larger Doncaster East Internal Drainage Board, formed by the amalgamation of the Finningley IDB with six other internal drainage boards.
Above Idle Stop, the river flows through an area where drainage was the responsibility of the Rivers Idle and Ryton Internal Drainage Board. The IDB was re-formed in 1987, its responsibilities having previously been performed by the Severn Trent Water Authority, and managed 53 miles (85 km) of watercourses. Those to the west of the Idle drain into the river by gravity at a number of locations, but the region to the east of the river and to the north of Retford drains to a single outfall at Wiseton, where a pumping station pumps the water into the river when river levels are too high for gravity flow.
In April 2011, the Rivers Idle and Ryton IDB amalgamated with the Isle of Axholme IDB, Garthorpe IDB and Everton IDB, to become the Isle of Axholme and North Nottinghamshire Water Level Management Board. The move was initiated by the Department for Environment, Food and Rural Affairs (DEFRA), who saw this and other similar amalgamations as a way to increase efficiency, and to allow them to better support Local Flood Authorities.
The river is navigable for around 11 miles (18 km) from West Stockwith to Bawtry. It is quite possible that Bawtry acted as a sea port from Roman times, but little is known of this early period. However, it was associated with the sea by the 12th century, when the parish church was dedicated to St Nicholas, the patron saint of seafarers, and the Hundred Rolls of 1276 listed it as a port. There are records of lead being shipped during the early 1300s, and wool was shipped to Dordrecht from Nottinghamshire via Hull in 1337. The prosperous trading community there suffered a downturn in the early 16th century, but subsequently recovered, with lead being shipped directly to London in 1596. In the same year, a ford constructed across the Bycarrsdyke was described as "a great hinderance to navigation."
Following the construction of the lock at Misterton Soss, which had guillotine gates, any sailing vessels using the river had to lower their masts, and although trade increased during the 17th century, the size of boats on the river tended to be smaller, with their cargoes being transhipped into larger vessels once they reached the Trent. The destruction of the drainage works and the lock during riots in 1643 meant that ships could again reach Bawtry, and lead was shipped directly to Amsterdam in 1645. A new sluice was built in 1645, which probably had mitred gates at its upper end and a guillotine gate at its lower end, but around 1724 it was rebuilt with two sets of mitred gates both pointing towards the Trent, which hindered navigation because the river level above the structure could not be maintained. Of the 4,415 tons of goods handled by Bawtry wharf in 1767, over 25 percent was lead, but trade had been declining for some years. The opening of the Chesterfield Canal in 1777 and the Great Northern Railway through Bawtry in 1849 saw most trade on the river cease. Misterton Soss was rebuilt in 1833 as a three-arched bridge, with gates and boards to control the river level. The upper gates of the lock were turned to face upstream, so that vessels could only pass through when the Idle and Trent made a level.
The fourth edition of Inland Waterways of Great Britain, published in 1962 stated that the river was navigable as far as Bawtry for boats with a draught of 2.5 feet (0.76 m), and that smaller boats could continue upstream for a further 8 miles (13 km). This was still the accepted wisdom in 1985, when the sixth edition was published, although after 1963 and the demolition of Misterton Soss, few boats could reach Bawtry, and those that attempted to make the journey reported that there were obstructions on the river bed. Boats could only enter the river when the falling tide on the Trent was level with the water in the Idle.
Since the drainage works of 1981, access to the Idle is through the two sluice gates at the mouth of the river, and so the Environment Agency, who are responsible for the waterway, require 48 hours notice of intent to enter it. There is also a high toll for doing so, with the result that most boaters that enter the river do so as part of a group, so that the cost can be shared. The space between the two sluices is effectively used as a very large lock, capable of holding a number of boats. Entrance through the first sluice is only possible for an hour either side of high tide. The Environment Agency also require all boaters to sign an indemnity form, which absolves them of any responsibility for loss or damage to boats.
Boats using the river can reach Bawtry bridge. Size is restricted to 59.7 by 18 feet (18.2 by 5.5 m), with a draft of 2.5 feet (0.76 m) and headroom of 9 feet (2.7 m). There are no public moorings. Large boats can turn round with care either side of Bawtry bridge, and at the point where the River Ryton joins the Idle. Above this point, the river can be navigated by canoes all the way from its source. Access to the river can be gained from a bridge over the River Meden some 110 yards (100 m) above the junction with the River Maun, where the Idle starts.
The river also provides water for the Chesterfield Canal. A feeder was constructed in the 1770s, which left the river some 2 miles (3.2 km) above the Retford aqueduct, so that water could flow by gravity to the canal. This arrangement was replaced by an electric pumping station at the foot of the aqueduct in the 1970s.
Conservation
There are four areas of grassland adjacent to the lower Idle, which are subject to periodic flooding, and which provide habitat for wintering and breeding birds. They form the Idle Washlands Site of Special Scientific Interest (SSSI). Historically, a much greater area would have functioned in this way, but much of it is now cut off from the river by high flood defence banks. The Washlands SSSI once covered an area of 250 hectares, which was used as grazing pasture during the summer months and was often covered by shallow flooding in the winter, but during the 1980s, further flood defence work and land drainage reduced this area to 88 hectares. Some work has been carried out under the National Environment Programme to ensure that the wildfowl and wader habitat is not lost completely, and the Environment Agency have produced a water level management plan to further protect the SSSI. Parts of the Mother Drain are also a designated SSSI.
Further up-river, some 781 acres (316 ha) of the Sutton and Lound gravel pits have been designated as an SSSI since 2002. They were part of an active quarrying operation run by the construction group Tarmac between the late 1940s and 2012. Tarmac sold part of the quarry to the Nottinghamshire Wildlife Trust in 1989, and after years of restoration work, the SSSI designation was achieved. It is now known as the Idle Valley Nature Reserve, and a building to house the Rural Learning Centre was completed in 2008, overlooking Belmoor Lake. Tarmac gave the Trust further land in 2009, as quarrying operations wound down, and the reserve was extended as land was acquired from Hanson Quarries. When EDF Energy closed their paraformaldehyde disposal plant in the 1990s, the settling lagoons became part of the reserve, although most of their site was returned to farmland. A total of 1,100 acres (450 ha) are now managed by the Trust, making it one of the largest nature conservation sites in the East Midlands.
The pits provide an important wetland habitat for a large variety of birds. They won the 2008 "British Trust for Ornithology – British Energy Business Bird Challenge" in the category for quarries over 100 ha. A total of 172 different species of birds were recorded, including a number of birds which normally occupy the coastal fringes rather than inland sites. These include ringed plover, little ringed plover, shelduck and oystercatchers. The Nottinghamshire Wildlife Trust have been active in planting reeds to improve the habitat, which were grown at Langford Quarry in a joint venture between Tarmac and the Royal Society for the Protection of Birds. Recording of birds at the site has been taking place since 1951, and 271 distinct species have been identified. The reserve also provides habitat for smaller animals, including 600 species of moths, 28 species of butterflies, and 19 species of dragonflies.
Course
The river is largely rural in character, although it passes through the centre of Retford and skirts the south-eastern fringe of Bawtry. The village of Eaton, on the southern edge of the town of East Retford, is believed to occupy the site of a battle in 616 in which the East Angles under Raedwald defeated the Northumbrians under Æthelfrith, and Æthelfrith was killed. The battle resulted in the establishment of Edwin as king of Northumbria.
Bawtry bridge, which carries the A631 road to Gainsborough over the river, was constructed in 1810 by Mr Flavel of Wetherby, at a cost of £3,000. It consists of a large central arch flanked by a slightly smaller arch on both sides. The road was widened in 1940, by extending the bridge on its south side, but retains its original character because the south facade was carefully removed and reused to face the new construction.
Point | Coordinates (Links to map resources) |
OS Grid Ref | Notes |
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Source | 53°16′06″N 0°56′53″W / 53.2684°N 0.9480°W | SK702751 | Rivers Meden and Maun join |
Retford Aqueduct | 53°19′09″N 0°56′48″W / 53.3192°N 0.9466°W | SK702807 | Chesterfield Canal crosses |
Sutton Weir | 53°20′35″N 0°57′40″W / 53.3430°N 0.961°W | SK692834 | |
Wiseton pumping stn | 53°23′47″N 0°55′55″W / 53.3965°N 0.9320°W | SK711893 | Idle and Ryton IDB |
Bawtry Bridge | 53°25′36″N 1°00′51″W / 53.4268°N 1.0143°W | SK655926 | Limit of navigation |
Austerfield pumping stn | 53°26′22″N 0°59′53″W / 53.4394°N 0.9981°W | SK666940 | Finningley IDB |
Scaftworth pumping stn | 53°26′11″N 0°59′34″W / 53.4363°N 0.9929°W | SK670937 | Everton IDB |
Gringley pumping stn | 53°26′46″N 0°55′43″W / 53.4461°N 0.9285°W | SK712949 | Everton IDB |
Idle Stop and PS | 53°27′39″N 0°54′54″W / 53.4609°N 0.9149°W | SK721965 | Former course turned north |
Hunters Hill pumping stn | 53°27′36″N 0°51′38″W / 53.4599°N 0.8606°W | SK757965 | Finningley IDB |
Misterton Soss | 53°26′50″N 0°49′46″W / 53.4472°N 0.8295°W | SK778951 | Former pumping stns |
Outlet pumping stn | 53°26′45″N 0°48′59″W / 53.4457°N 0.8165°W | SK787949 | inc. navigable sluice |
Entrance sluice | 53°26′37″N 0°48′46″W / 53.4436°N 0.8127°W | SK789947 | vertical lifting gate |
Water quality
The Environment Agency measure the water quality of the river systems in England. Each is given an overall ecological status, which may be one of five levels: high, good, moderate, poor and bad. There are several components that are used to determine this, including biological status, which looks at the quantity and varieties of invertebrates, angiosperms and fish, and chemical status, which compares the concentrations of various chemicals against known safe concentrations. Chemical status is rated good or fail.
The water quality of the River Idle system was as follows in 2016.
Section | Ecological Status | Chemical Status | Overall Status | Length | Catchment | Channel |
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Idle from Maun/Poulter to Tiln | Moderate | Good | Moderate | 7.8 miles (12.6 km) | 19.71 square miles (51.0 km2) | |
Ranskill Brook Catchment (trib of Idle) | Moderate | Good | Moderate | 6.0 miles (9.7 km) | 10.48 square miles (27.1 km2) | |
Idle from Tiln to Ryton | Moderate | Good | Moderate | 11.2 miles (18.0 km) | 23.15 square miles (60.0 km2) | |
Idle from Ryton to Trent | Moderate | Good | Moderate | 11.7 miles (18.8 km) | 24.04 square miles (62.3 km2) | artificial |
The reasons for the quality being less than good include sewage discharge affecting most of the river, ground water abstraction, and poor management of agricultural and rural land adjacent to the river system.