The River Cam () is a chalk river and the main river flowing through Cambridge in eastern England. After leaving Cambridge, it flows north and east before joining the River Great Ouse to the south of Ely, at Pope's Corner. The total distance from Cambridge to the sea is about and is navigable for punts, small boats, and rowing craft. The Great Ouse also connects to England's canal system via the Middle Level Navigations and the River Nene. In total, the Cam runs for around from its furthest source (near Widdington in Essex) to its confluence with the Great Ouse.
Name The original name of the river was the Granta and (unusually) its present name derives from the city of Cambridge () rather than the other way around: After the city's present name developed in Middle English, the river's name was backformed to match. In earlier times even the lower part of the Cam was named the Granta, but after the name of the Anglo-Saxon town of Grantebrycge had been modified to Cambridge, the river was renamed to match. This was not universally applied, however, and the upper stretch of the river continues to be informally known as the Granta. It has been saidBedders, Bulldogs and Bedells: A Cambridge Glossary, (1995), Frank Stubbings, Cambridge University Press, , p. 19 that the river is the "Granta" above the Silver Street Bridge (in Cambridge) and the "Cam" below it. The confluence of River Rhee is about 4.7 km upstream of Silver Street bridge.
In the Ordnance Survey map, the Granta tributary is called "River Cam or Granta",https://osdatahub.os.uk/data/downloads/open → Download Ordonance Survey 1:250.000 → tile id=TL and in the public environment database is the Cam.Environment Data, Catchment, Cam Rhee and Granta Operational Catchment Water bodies It has a small tributary named Granta, unequivocally.
The Rhee tributary, in the Ordnance Survey map is called "River Cam or Rhee".
Minor tributary Another minor tributary is Bourn Brook which has its source near the village of Eltisley, west of Cambridge, running east through Caxton, Bourn and Toft to join the Cam at Byron's Pool.
The upper river The upper course of the Cam starts near the village of Widdington in Essex, flowing north past Audley End House to merge with the other contributary Rhee, which is also commonly called River Cam, a mile south of Grantchester. From source to its confluence with the Rhee it is in length, or according to Environment Data, .
The lower river
The lower River from Hauxton Junction to the junction on the Ely Ouse has a length of .Environment Data: Cam Lower
An organisation called the Conservators of the River Cam was formed in 1702, charged with keeping the river navigable. The Conservators are responsible for the two locks in and north east of Cambridge: Jesus Lock and Baits Bite Lock. The stretch north (downstream) of Jesus Lock is sometimes called the lower river.
The stretch between Jesus Lock and Baits Bite Lock is much used for rowing. There are also many residential boats on this stretch, their occupants forming a community who call themselves the Camboaters.
Navigation on the lowest section of the Cam, below and including Bottisham Lock, is the responsibility of the Environment Agency.Environment Agency - River Great Ouse
From Jesus Lock and the Backs to Grantchester (middle and upper river)
The stretch above Jesus Lock is sometimes known as the middle river (with the section above the Mill Pond being referred to as the upper river). Between Jesus Lock and the Mill Pond, it passes through the Backs below the walls of many of the colleges. This is the section of river most popular with tourists, with its picture-postcard views of elegant bridges, green lawns and graceful willows. This stretch also has the unusual feature of the remains of a submerged towpath: the riverside colleges did not permit barge horses on the Backs, so the beasts waded up the Cam to the mill pulling their loads behind them.
Access for mechanically powered boats is prohibited above 'La Mimosa' Pub (at the upstream end of Jesus Green) between 1 April and 30 September, when the middle and upper river are open only to manually propelled craft. The most common of these are the flat-bottomed punts.
Between 1 October and 31 March powered boats are allowed as far as Mill Pool, but few people take advantage of this, as there are very few public mooring places along the Backs, and the river is too narrow and the bridges too low to afford easy passing or turning for many boats.
Punts and canoes can be manhandled around the weir above the Mill Pool by means of the rollers, a slipway from lower to upper level. From the Mill Pool and its weir, the river can be followed upstream through Grantchester meadows to the village of Grantchester and Byron's Pool, where it is fed by many streams.
Tributaries The two principal tributaries of the Cam are the Granta and the Rhee, though both are also known as the Cam.Ordnance Survey of Great Britain. 1:25000
Rhee The Rhee begins just off the High Street (Ashwell Springs), at Ashwell in Hertfordshire. Running north out of Ashwell, it forms the county boundary between Bedfordshire and Hertfordshire for around two kilometres, then the boundary between Bedfordshire and Cambridgeshire for a further kilometre. At this point its course turns east and from here until it merges with the Granta it forms the parish boundary between a succession of villages, though until it reaches Barrington it remains at a distance of around a kilometre from any settlement of any size.
Just after flowing under the Roman Ermine Street, it crosses the avenue of Wimpole Hall and a few kilometres later it receives the waters of the minor River Mel that runs through Meldreth. It runs along the southern edge of the village of Barrington, where it still powers a water mill known as Bulbeck Mill. At Harston it passes Harston Mill, the site of a water mill from at least the 11th century until the need for mills died out in the mid-20th century, and the parish church of All Saints. It then touches the eastern edge of the village of Haslingfield before joining the Granta at Hauxton Junction. From source to its confluence with the Granta it is in length.
"Granta", upper course of the Cam
The Granta is the longer one and officially defined as the upper course of the Cam.Environment Data: Waterbody GB105033037480, Cam upstream of Newport The headwaters of the Cam start in the parish of Debden to the east of the village of Widdington in Essex. After initially running south west to descend from the hills of Uttlesford, it turns north just west of the village of Henham. From there until Great Shelford it largely follows the course of the West Anglia Main Line railway. Its northward journey passes first through Newport, where it is joined by the streams known as Wicken Water and Debden Water. A couple of miles later it forms a picturesque addition to views of the stately home as it flows past the front of Audley End House, and is also joined by the stream known as Fulfen Slade. It then skirts the edges of a number of villages as it moves into Cambridgeshire, successively Littlebury, Little Chesterford, Great Chesterford, Ickleton, Hinxton, Duxford and Whittlesford, powering a number of water mills along the way. Forming the boundary between Great Shelford and Little Shelford, it turns west to flow past Hauxton to merge with the Rhee a mile south of Grantchester at Hauxton Junction. From source to its confluence with the Rhee it is in length.
Granta The real Granta is a tributary of the upper Cam. It runs from south of Haverhill to join the Cam south of Great Shelford. Another minor tributary is Bourn Brook which has its source near the village of Eltisley, west of Cambridge, running east through Caxton, Bourn and Toft to join the Cam at Byron's Pool.
Literature "The Reeve's Tale" from Geoffrey Chaucer's Canterbury Tales begins:
The mill formerly stood by Brasley Bridge on Grantchester Road. The mill pond is extant and the foundations of the mill can be seen when the water is low.
Byron's Pool is named after the poet, Lord Byron, who is reputed to have swum there. It was certainly a bathing place for Rupert Brooke and the Cambridge neo-Pagans. Brooke used to canoe from Cambridge to lodgings in Grantchester, which included the Old Vicarage. His homesick poem of 1912 evokes the river:
One of Brooke's contemporaries, Gwen Darwin, later Raverat, grew up in the old mill by the Mill Pond. Her book, Period Piece, is a memoir of a childhood messing about on the river. The mill house is now part of Darwin College.
Children's author Philippa Pearce, who lived in Great Shelford until her death in December 2006, featured the Cam in her books, most notably Minnow on the Say. The river is renamed the River Say, with Great and Little Shelford becoming Great and Little Barley, and Cambridge becoming "Castleford" (not to be confused with the real town of the same name in West Yorkshire).
River Cam is referred to as "Camus, reverend Sire" in line 103 of John Milton's pastoral elegy Lycidas. Edward King, in whose memory the elegy was composed, was a fellow student at Cambridge.
Use for recreation
Like many rivers, the Cam is extensively used for several forms of recreational activity. These include angling, swimming and various kinds of boating.
Angling The water is not murky and is clean enough from its source to its confluence with the Great Ouse to support fish. The fishing rights on the west bank are leased annually to the Cambridge Fish Preservation and Angling Society.
The Cam below Bottisham Sluice may still hold burbot, a fish thought to be extinct in English waters since the early 1970s.UK Biodiversity Action Plan, Burbot , accessed 10 January 2009 The last known burbot caught in Britain was in 1969, on the Cam, and in 2010 a fisherman reported spotting two in the Great Ouse.
Above Hinxton and Great Chesterford the river holds a stock of wild brown trout, though it is also stocked by the Audley Fly Fishers club and other angling societies who own the rights.
Boating All boats using the river downstream of Mill Pond require a navigation licence from either the Conservators of the River Cam or the Environment Agency.
There are public moorings just below Jesus Lock on both sides of the river and on the western bank just north of the bridge at Clayhithe (both with a maximum stay of 48 hours), and unofficial moorings on the railings adjoining Riverside in Cambridge (unlimited stay, but usually fully occupied) which are under review by Cambridge City Council and likely to be reduced to eight or nine formalised residential moorings, or removed altogether. The moorings on the commons in Cambridge (Jesus Green, Midsummer Common and Stourbridge Common) are reserved by the City Council for holders of its long-term mooring permits. There are also some privately owned moorings.
There is a public slipway next to the garden of the Green Dragon pub in Water Street, Chesterton. This is occasionally used for launching small boats.
Punting
Punting is the most popular form of boating on the stretch of the river between Jesus Lock and Grantchester. Several of the colleges own punts, and they can also be hired from various companies, either with or without a person to operate them. The colleges and at least one private operator also own punts which are available for members of the public to travel on.
Canoeing Canoeing and kayaking, both recreational and competitive, are popular at all times of year, especially on the section above the Mill Pond towards Grantchester. Both Cambridge Canoe Club (on Sheep's Green) and Cambridge University Canoe Club (just upstream from Newnham) are based here. Standup paddle boarding has also become popular.
Powered boating