right|thumb|The Trent passes over a man-made waterfall in Hollin Wood just downstream from its source
The Trent, the third-longest river in the United Kingdom, has its source in Staffordshire, on the southern edge of Biddulph Moor. It flows through and drains the North Midlands into the Humber Estuary. The river is known for dramatic flooding after storms and spring snowmelt, which in the past have often caused the river to change course.
The river passes through Stoke-on-Trent, Stone, Staffordshire, Rugeley, Burton-upon-Trent, Nottingham, Newark-on-Trent and Gainsborough before joining the Yorkshire Ouse at Trent Falls to form the Humber Estuary, which empties into the North Sea between Kingston upon Hull in Yorkshire and Immingham in Lincolnshire. The wide Humber estuary has often been characterised as the boundary between the Midlands and Northern England ("The North").
Name
The name "Trent" is possibly from a Romano-British word meaning "strongly flooding". More specifically, the name may be a contraction of two Romano-British words, tros ("over") and hynt ("way"). This may indeed indicate a river that is prone to flooding. However, a more likely explanation may be that it was considered to be a river that could be crossed principally by means of fords, i.e. the river flowed over major road routes. This may explain the presence of the Romano-British element rid (cf. Welsh rhyd, "ford") in various place names along the Trent, such as Hill Ridware, as well as the Old English‐derived ford. Another translation is given as "the trespasser", referring to the waters flooding over the land. According to Koch at the University of Wales, the name Trent derives from the Romano-British Trisantona, a Romano-British reflex of the combined elements *tri-sent(o)-on-ā- (through-path-augmentative-feminine-) ‘great thoroughfare’.
Course
The Trent rises within the Staffordshire Moorlands district, near the village of Biddulph Moor, from a number of sources including the Trent Head Well. It is then joined by other small streams to form the Head of Trent, which flows south, to the only reservoir along its course at Knypersley Reservoir. Downstream of the reservoir it passes through Stoke-on-Trent and merges with the Lyme, Fowlea and other brooks that drain the six towns of the Staffordshire Potteries to become the River Trent. On the southern fringes of Stoke, it passes through the landscaped parkland of Trentham Gardens.
thumb|right|[[Swarkestone Bridge]]
The river then continues south through the market town of Stone, and after passing the village of Salt, it reaches Great Haywood, where it is spanned by the 16th-century Essex Bridge near Shugborough Hall. At this point the River Sow joins it from Stafford. The Trent now flows south-east past the town of Rugeley until it reaches Kings Bromley where it meets the Blithe. After the confluence with the Swarbourn, it passes Alrewas and reaches Wychnor, where it is crossed by the A38 road dual carriageway, which follows the route of the Roman Ryknild Street. The river turns north-east where it is joined by its largest tributary, the River Tame (which is at this point actually the larger, though its earlier length shorter) and immediately afterwards by the River Mease, creating a larger river that now flows through a broad floodplain.
The river continues north-east, passing the village of Walton-on-Trent until it reaches the large town of Burton-upon-Trent. The river in Burton is crossed by a number of bridges including the ornate 19th-century Ferry Bridge that links Stapenhill to the town.
It then reaches the town of Gainsborough with its own Trent Bridge. The river frontage in the town is lined with warehouses, that were once used when the town was an inland port, many of which have been renovated for modern use. Downstream of the town the villages are often named in pairs, representing the fact that they were once linked by a river ferry between the two settlements. These villages include West Stockwith and East Stockwith, Owston Ferry and East Ferry, and West Butterwick and East Butterwick. At West Stockwith the Trent is joined by the Chesterfield Canal and the River Idle and soon after enters Lincolnshire fully, passing to the west of Scunthorpe. The last bridge over the river is at Keadby where it is joined by both the Stainforth and Keadby Canal and the River Torne. An abandoned channel at Repton is described on an old map as 'Old Trent Water', records show that this was once the main navigable route, with the river having switched to a more northerly course in the 18th century.<!-- I think this was the tithe map for Repton or Ingleby - 1850s --> Farther downstream at Hemington, archaeologists have found the remains of a medieval bridge across another abandoned channel.<!-- This came from a lecture given by a professional archaeologist: it is probably published somewhere --> Researchers using aerial photographs and historical maps have identified many of these palaeochannel features, a well-documented example being the meander cutoff at Sawley. The river's propensity to change course is referred to in Shakespeare's play Henry IV, Part 1:
Henry Hotspur's speech complaining about the river has been linked to the meanders near West Burton, however, given the wider context of the scene, in which conspirators propose to divide England into three after a revolt, it is thought that Hotspur's intentions were of a grander design, diverting the river east towards the Wash such that he would benefit from a much larger share of the divided Kingdom. Downstream of Burton upon Trent, the river increasingly trends northwards, cutting off a portion of Nottinghamshire and nearly all of Lincolnshire from his share, north of the Trent. This took place in 1593 so would have been a contemporary topic in the Shakespearean period.
Prehistory
During the Pleistocene epoch (1.7 million years ago), the River Trent rose in the Welsh hills and flowed almost east from Nottingham through the present Vale of Belvoir to cut a gap through the limestone ridge at Ancaster and thence to the North Sea. At the end of the Wolstonian Stage (c. 130,000 years ago) a mass of stagnant ice left in the Vale of Belvoir caused the river to divert north along the old Lincoln river, through the Lincoln gap, along what is now the course of the Witham. During a following glaciation (Devensian, 70,000 BC) the ice held back vast areas of water – called Glacial Lake Humber – in the current lower Trent basin. When this retreated, the Trent adopted its current course into the Humber.
Catchment
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The Trent basin covers a large part of the Midlands, and includes the majority of the counties of Staffordshire, Derbyshire, Leicestershire, Nottinghamshire and the West Midlands; but also includes parts of Lincolnshire, South Yorkshire, Warwickshire and Rutland. The catchment is located between the drainage basins of the Severn and its tributary the Avon to the south and west, the Weaver to the north-west, the tributaries of the Yorkshire Ouse to the North and the basins of the Welland, Witham and Ancholme to the east.
A distinctive feature of the catchment is the marked variation in the topography and character of the landscape, which varies from the upland moorland headwaters of the Dark Peak, where the highest point of the catchment is the Kinder Scout plateau at ; through to the intensively farmed and drained flat fenland areas that exist alongside the lower tidal reaches, where ground levels can equal sea level. These lower reaches are protected from tidal flooding by a series of floodbanks and defences.
Elsewhere there is a distinct contrast between the open limestone areas of the White Peak in the Dove catchment, and the large woodland areas, including Sherwood Forest in the Dukeries area of the Idle catchment, the upland Charnwood Forest, and the National Forest in the Soar and Mease drainage basins respectively.
Water level management is important in these lowland areas, and the local watercourses are usually maintained by internal drainage boards and their successors, with improved drainage being assisted by the use of pumping stations to lift water into embanked carrier rivers, which subsequently discharge into the Trent.
The less populous rural areas are offset by a number of large urbanised areas including the conurbations of Stoke-on-Trent, Birmingham and the surrounding Black Country in the West Midlands; and in the East Midlands the major university cities and historical county seats of Leicester, Derby and Nottingham. Together these contain the majority of the 6 million people who live in the catchment.
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Downstream of Armitage the solid geology is primarily Mercia Mudstones, the course of the river following the arc of these mudstones as they pass through the Midlands all the way to the Humber. The mudstones are not exposed by the bed of the river, as there is a layer of gravels and then alluvium above the bedrock. In places, however the mudstones do form river cliffs, most notably at Gunthorpe and Stoke Lock near Radcliffe on Trent, the village being named after the distinctive red coloured strata.
The low range of hills, which have been formed into a steep set of cliffs overlooking the Trent between Scunthorpe and Alkborough are also made up of mudstones, but are of the younger Rhaetic Penarth Group.
This ‘staircase’ of flat topped terraces was created as a result of successive periods of deposition and subsequent down cutting by the river, a product of the meltwater and glacially eroded material produced from ice sheets at the end of glacial periods through the Pleistocene epoch between 450,000 and 12,000 years BP. Contained within these terraces is evidence of the mega fauna that once lived along the river, the bones and teeth of animals such as the woolly mammoth, bison and wolves that existed during colder periods have all been identified. Another notable find in a related terrace system near Derby from a warmer interglacial period, was the Allenton hippopotamus. Once worked out, the remaining gravel pits which are usually flooded by the relatively high water table have been reused for a wide variety of purposes. These include recreational water activities, and once rehabilitated, as nature reserves and wetlands.
During the end of the last Devensian glacial period the formation of Lake Humber in the lowest reaches of the river, meant that substantial lake bed clays and silts were laid down to create the flat landscape of the Humberhead Levels. These levels extend across the Trent valley, and include the lower reaches of the Eau, Torne and Idle. In some areas, successive layers of peat were built up above the lacustrine deposits during the Holocene period, which created lowland mires such as the Thorne and Hatfield Moors.
Hydrology
The topography, geology and land use of the Trent catchment all have a direct influence on the hydrology of the river. The variation in these factors is also reflected in the contrasting runoff characteristics and subsequent inflows of the principal tributaries. The largest of these is the River Tame, which contributes nearly a quarter of the total flow for the Trent, with the other significant tributaries being the Derwent at 18%, Soar 17%, the Dove 13%, and the Sow 8%. Four of these main tributaries, including the Dove and Derwent which drain the upland Peak District, all join within the middle reaches, giving rise to a comparatively energetic river system for the UK.
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Rainfall
Rainfall in the catchment generally follows topography with the highest annual rainfall of and above occurring over the high moorland uplands of the Derwent headwaters to the north and west, with the lowest of , in the lowland areas to the north and east. Rainfall totals in the Tame are not as high as would be expected from the moderate relief, due to the rain shadow effect of the Welsh mountains to the west, reducing amounts to an average of for the tributary basin.
The average for the whole Trent catchment is which is significantly lower than the average for United Kingdom at and lower than that for England at .
Like other large lowland British rivers, the Trent is vulnerable to long periods of rainfall caused by sluggish low pressure weather systems repeatedly crossing the basin from the Atlantic, especially during the autumn and winter when evaporation is at its lowest. This combination can produce a water-logged catchment that can respond rapidly in terms of runoff, to any additional rainfall. Such conditions occurred in February 1977, with widespread flooding in the lower reaches of the Trent when heavy rain produced a peak flow of nearly at Nottingham. In 2000 similar conditions occurred again, with above average rainfall in the autumn being followed by further rainfall, producing flood conditions in November of that year.
Another meteorological risk, although one that occurs less often, is that related to the rapid melting of snow lying in the catchment. This can be a result of a sudden rise in temperature after a prolonged cold period, or when combined with extensive rainfall. Many of the largest historical floods were caused by snowmelt, but the last such episode occurred when the bitter winter of 1946–7 was followed by a rapid thaw due to rain in March 1947 and caused severe flooding all along the Trent valley.
At the other extreme, extended periods of low rainfall can also cause problems. The lowest flows for the river were recorded during the drought of 1976, following the dry winter of 1975/6. Flows measured at Nottingham were exceptionally low by the end of August, and were given a drought return period of greater than one hundred years.
Discharge
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!colspan=11|Discharge of the River Trent at various locations
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!scope=row|Stoke on Trent
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The river's flow is measured at several points along its course, at a number of gauging stations. At Stoke-on-Trent in the upper reaches, the average flow is only , which increases considerably to , at Great Haywood, as it includes the flow of the upper tributaries draining the Potteries conurbation. At Yoxall, the flow increases to due to the input of larger tributaries including the Sow and Blithe. At Drakelow upstream of Burton the flow increases nearly three-fold to , due to the additional inflow from the largest tributary the Tame. At Colwick near Nottingham, the average flow rises to , due to the combined inputs of the other major tributaries namely the Dove, Derwent and Soar. The last point of measurement is North Muskham here the average flow is , a relatively small increase due to the input of the Devon, and other smaller Nottinghamshire tributaries.
The Trent has marked variations in discharge, with long term average monthly flows at Colwick fluctuating from in July during the summer, and increasing to in January.
During lower flows the Trent and its tributaries are heavily influenced by effluent returns from sewage works, especially the Tame where summer flows can be made up of 90% effluent. For the Trent this proportion is lower, but with nearly half of low flows being made up of these effluent inflows, it is still significant. There are also baseflow contributions from the major aquifers in the catchment.
Average monthly flows of Trent in cubic metres per second measured at Colwick (Nottingham).
Warp was also used as a commercial product, after being collected from the river banks at low tide, it was transported along the Chesterfield Canal to Walkeringham where it was dried out and refined to be eventually sold as a silver polish for cutlery manufacturers.
Floods
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!colspan=6| Largest floods on the River Trent at Nottingham
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One of the earliest recorded floods along the Trent was in 1141, and like many other large historical events was caused by the melting of snow following heavy rainfall, it also caused a breach in the outer floodbank at Spalford. Some of the earliest floods can be assessed by using Spalford bank as a substitute measure for the size of a particular flood, as it has been estimated that the bank only failed when flows were greater than , the bank was also breached in 1403 and 1795.
Early bridges were vulnerable to floods, and in 1309 many bridges were washed away or damaged by severe winter floods, including Hethbeth Bridge. In 1683 the same bridge was partially destroyed by a flood that also meant the loss of the bridge at Newark. Historical archives often record details of the bridge repairs that followed floods, as the cost of these repairs or pontage had to be raised by borrowing money and charging a local toll. In Nottingham, residents of Narrow Marsh were trapped by the floodwaters in their first floor rooms, boats were used to take supplies to those stranded. Livestock was badly affected, 72 sheep drowned in Wilford and ten cows were lost in Bridgford. The vulnerable flood bank at Spalford was breached again, floodwaters spreading out across the low-lying land, even reaching the River Witham and flooding Lincoln. Some were flooded for a period of over three weeks.
right|thumb|Flood marks at [[Girton, Nottinghamshire|Girton showing the height of the 1795 flood and others]]
A description of the breach was given as follows:
<blockquote>The bank is formed upon a plain of sandy nature, and when it was broken in 1795, the water forced an immense breach, the size of which may be judged from the fact that eighty loads of faggots and upwards of four hundred tons of earth were required to fill up the hole, an operation which took several weeks to complete.</blockquote>
The flood bank was subsequently strengthened and repaired, following further floods during 1824 and 1852. In Newark the water was deep enough to allow four grammar school boys to row across the countryside to Kelham. The flood marks at Girton show that this flood was only lower than that of 1795, when the village was flooded to a depth of .
Flooding on the Trent can also be caused by the effects of storm surges independently of fluvial flows, a series of which occurred during October and November 1954, resulting in the worse tidal flooding experienced along the lower reaches. These floods revealed the need for a tidal protection scheme, which would cope with the flows experienced in 1947 and the tidal levels from 1954, and subsequently the floodbanks and defences along the lower river were improved to this standard with the works being completed in 1965. In December 2013, the largest storm surge since the 1950s occurred on the Trent, when a high spring tide combined with strong winds and a low pressure weather system, produced elevated tidal river levels in the lower reaches. The resulting surge overtopped the flood defences in the area near Keadby and Burringham, flooding 50 properties.thumb|left|
The fifth largest flood recorded at Nottingham occurred in November 2000, with widespread flooding of low-lying land along the Trent valley, including many roads and railways. The flood defences around Nottingham and Burton constructed during the 1950s, following the 1947 event, stopped any major urban flooding, but problems did occur in undefended areas such as Willington and Gunthorpe, and again at Girton where 19 houses were flooded.
History of navigation
Nottingham seems to have been the ancient head of navigation until the Restoration, due partly to the difficult navigation of the Trent Bridge. Navigation was then extended to Wilden Ferry, near to the more recent Cavendish Bridge, as a result of the efforts of the Fosbrooke family of Shardlow.
Later, in 1699, the baron William Paget (Lord Paget), who owned coal mines and land in the area, obtained an act of Parliament, the (10 Will. 3. c. 26), to extend navigation up to Fleetstones Bridge, Burton, despite opposition from the people of Nottingham. Lord Paget seems to have funded the work privately, building locks at King's Mill and Burton Mills and several cuts and basins. The act gave him absolute control over the building of any wharves and warehouses above Nottingham Bridge. Lord Paget leased the navigation and the wharf at Burton to George Hayne, while the wharf and warehouses at Wilden were leased by Leonard Fosbrooke, who held the ferry rights and was a business partner of Hayne. The two men refused to allow any cargo to be landed which was not carried in their own boats, and so created a monopoly.
In 1748, merchants from Nottingham attempted to end this monopoly by landing goods on the banks and into carts, but Fosbrooke used his ferry rope to block the river, and then created a bridge by mooring boats across the channel, and employing men to defend them. Hayne subsequently scuppered a barge in King's Lock, and for the next eight years goods had to be transhipped around it. Despite a Chancery injunction against them, the two men continued with their action. Hayne's lease expired in 1762, and Lord Paget's son, the Earl of Uxbridge, gave the new lease to the Burton Boat Company. The canal ran parallel to the upper river to Burton upon Trent, where new wharfs and warehouses at Horninglow served the town, and the Burton Boat Company were unable to repair the damaged reputation of the river created by their predecessors. Eventually in 1805, they reached an agreement with Henshall & Co., the leading canal carriers, for the closure of the river above Wilden Ferry. Though the river is no doubt legally still navigable above Shardlow, it is probable that the agreement marks the end of the use of that stretch of the river as a commercial navigation.
The lower river
The first improvement of the lower river was at Newark, where the channel splits into two. The residents of the town wanted to increase the use of the branch nearest to them, and so the (13 Geo. 3. c. 86) was obtained in December 1772 to authorise the work. Newark Navigation Commissioners were created, with powers to borrow money to fund the construction of two locks, and to charge tolls for boats using them. The work was completed by October 1773, and the separate tolls remained in force until 1783, when they were replaced by a one-shilling (5p) toll whichever channel the boats used.
The aim of the improvements was to increase the minimum depth from to . By early 1796, the Beeston cut was operational, with the Cranfleet cut following in 1797, and the Holme cut in 1800, with the whole works being finished by 1 September 1801. The cost exceeded the authorised capital by a large margin, with the extra being borrowed, but the company continued to pay a 7 per cent dividend on the original shares and on those created to finance the new work. In 1823 and again in 1831, the Newark Navigation Commissioners proposed improvements to the river, so that larger vessels could be accommodated, but the Trent Navigation Company were making a good profit, and did not see the need for such work.
thumb|right|Newark Town Lock
With traffic still between 350,000 and 400,000 tonnes per year, Frank Rayner became the engineer in 1896, and the company were persuaded that major work was necessary if the navigation was to survive. The engineer for the Manchester Ship Canal, Sir Edward Leader Williams, was commissioned to survey the river, while negotiations with the North Staffordshire Railway, who owned the Trent and Mersey Canal and had maintained its viability, ensured that some of the clauses from previous acts of Parliament did not prevent progress. A plan to build six locks between Cromwell and Holme, and to dredge this section to ensure it was wide and deep was authorised by the Trent Navigation Act 1906 (6 Edw. 7. c. lvii). Raising finance was difficult, but some was subscribed by the chairman and vice-chairman, and construction of Cromwell Lock began in 1908. The Newark Navigation Commissioners financed improvements to Newark Town lock at the same time, and dredging of the channel was largely funded by selling the 400,000 tonnes of gravel removed from the river bed. At , Cromwell lock could hold a tug and three barges, and was opened on 22 May 1911. The transport of petroleum provided a welcome increase to trade on the river, but little more work was performed before the beginning of the First World War. Barges still transport gravel from pits at Girton and Besthorpe to Goole and Hull.
Navigation today
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The river is legally navigable for some below Burton upon Trent. However, for practical purposes, navigation above the southern terminus of the Trent and Mersey Canal (at Shardlow) is conducted on the canal, rather than on the river itself. The canal connects the Trent to the Potteries and on to Runcorn and the Bridgewater Canal.
Down river of Shardlow, the non-tidal river is navigable as far as the Cromwell Lock near Newark, except in Nottingham (Beeston Cut & Nottingham Canal) and just west of Nottingham, where there are two lengths of canal, Sawley and Cranfleet cuts. Below Cromwell lock, the Trent is tidal, and therefore only navigable by experienced, well-equipped boaters. Navigation lights and a proper anchor and cable are compulsory. Associated British Ports, the navigation authority for the river from Gainsborough to Trent Falls, insist that anyone in charge of a boat must be experienced at navigating in tidal waters.
The use of a maritime pilot on the Trent is not compulsory for commercial craft, but is suggested for those without any experience of the river. Navigation can be difficult, and there have been a number of incidents with ships running aground and in one case, striking Keadby Bridge. The most recent occurrence involved the Celtic Endeavour being aground near Gunness for ten days, finally being lifted off by a high tide.
Trent Aegir
thumb|The Trent Aegir seen from West Stockwith, [[Nottinghamshire, 20 September 2005]]
At certain times of the year, the lower tidal reaches of the Trent experience a moderately large tidal bore (up to high), commonly known as the Trent Aegir (named after the Norse sea god). The Aegir occurs when a high spring tide meets the downstream flow of the river. The funnel shape of the river mouth exaggerates this effect, causing a large wave to travel upstream as far as Gainsborough, Lincolnshire, and sometimes beyond. The Aegir cannot travel much beyond Gainsborough as the shape of the river reduces the Aegir to little more than a ripple, and weirs north of Newark-on-Trent, Nottinghamshire, stop its path completely.
The literal North/South divide
The Trent historically marked the boundary between Northern England and Southern England. For example, the administration of royal forests was subject to a different justice in eyre north and south of the river, and the jurisdiction of the medieval Council of the North started at the Trent. In addition to this, the University of Oxford was formerly divided into a northern nation and a southern nation, the former consisting of English people north of the River Trent and the Scots and the latter consisting of English people south of the Trent, the Irish, and the Welsh.
Some traces of the former division remain: the Trent marks the boundary between the provinces of two English Kings of Arms, Norroy and Clarenceux. This divide was also described in Michael Drayton's epic topographical poem, Poly-Olbion, The Sixe and Twentieth Song, 1622:
Pollution history
It is not clear when pollution first became an issue for the River Trent, but in the late 1880s, it had a thriving salmon fishery, with the river producing an annual catch of some 3,000 fish, a decade later, this had fallen to 100. The collapse of the fishery was due to the rapid population increase of the towns that developed following the Industrial Revolution. The tipping point being the introduction of piped water and a basic sewer network, which meant that effluent, which was previously stored in cesspits, was carried away through drains into the nearest brook.