Although there are now few UK rivers, certainly less than 15%, for which the flow regime can be considered natural, the rivers and streams have basically followed the same course since the last Ice Age, around 12,000 years ago. The need to drain land, to protect it from flooding, to control the flow of water for water supply or hydropower, or to use the watercourses for navigation, fishing or recreation, have all imposed change to the riverscape. As has been mentioned here before, there are 161 chalk streams in England, from Wessex flowing south into Christchurch Harbour, The Solent and the Channel, north into the Thames, the Thames Estuary in Kent those that flow into the Ouse and the Broads in East Anglia, as well as those that flow into the Humber and the North Sea in the Eastern Wolds of Lincolnshire and Yorkshire. Chalk streams are defined as those rising directly from the chalk and subsequently flow over younger Tertiary (sand and clay) deposits, or those that rise from chalk which was directly impacted by major glacial action during the Pleistocene Ice Age. London has its own chalk stream in the form of the River Wandle, which rises in Carshalton and flows for nine miles into the Thames at Wandsworth. It was considered an excellent trout stream in the sixteenth and seventeenth centuries and was famously fished by Lord Nelson, until industrialisation and pollution turned it, officially, into an open sewer right up to the 1960s. It was mentioned in The Compleat Angler by Isaak Walton, who described the trout caught there as ‘having marbled spots like a tortoise.’ Since then, the Wandle Piscators and the Environment Agency have cleaned it up, and it is now meant to host trout, sea trout and salmon, according to a certain Theo Pike in his book Trout in Dirty Places, although no-one has actually seen or caught one yet.
A River Runs Through It is the title of a book by Norman Maclean and a film directed by Robert Redford, with the opening line, ‘In our family there was no clear line between religion and fly fishing.’ We are told that they live in western Montana, ‘at the junction of great trout rivers…’ In London, several rivers run through it, although most now flow underground. Apart from The Wandle, the Lea, the Ravensbourne, the Brent and the Crane, most rivers are hidden under our feet. Though the main stream can be encased in some form of sewer, the brook in its course would be joined by many springs and rivulets which cannot enter the enclosed sewer and will simply follow the original course of the stream, which means that the watersheds are the same, and below the buildings, the strata are unaltered. Unknown to most Londoners, there is a whole system of underground rivers, ‘as intricate and mysterious as those which pour from cave to cave in the heart of the Pyrenees and, partly like them, unexplored,’ as Nicholas Barton states in his 1962 book, Lost Rivers of London. Perhaps these rivers are not ‘lost’, but merely hidden.
As is suggested in William Kent’s Encyclopaedia of London, ‘a river can sometimes be diverted, but it is a very hard thing to lose it altogether,’ The Westbourne flows from Hampstead Heath, with one source actually springing up in the crypt of University College School in Frognal. It flows down through West Hampstead to Kilburn, where it is joined by another tributary, and continues down through Paddington and into Hyde Park, where it used to flow into the Serpentine. After going down through Knightsbridge, it famously crosses the District and Circle Lines above Sloane Square Underground station in a massive iron conduit, flowing into the Thames at Chelsea Bridge.
The Fleet starts life in the Vale of Health pond, again on Hampstead Heath, flowing through the Hampstead Ponds, with another tributary coming from the damned lake at Kenwood House and then into the chain of Highgate Ponds. By the time the two sources unite at Camden Town, it has disappeared underground, passing under the Regent’s Canal, past King’s Cross, Farringdon Road, Holborn, up to where it was navigable until the 1730s, where it finally flows into the Thames at Blackfriars Bridge. If one stops and listens at a drain in Clerkenwell, one can hear the Fleet sewer below!
The Tyburn also arises on Hampstead Heath from the Shepherd’s Well and flows southwards down to Regent’s Park, then under Oxford Street and Piccadilly towards Green Park and Buckingham Palace, flowing into The Thames at Westminster. Beverley Brook is a minor open stream rising in Worcester Park, then flowing north through Wimbledon Common, and Richmond Park, and joining the River Thames to the north of Putney Embankment at Barn Elms.
To the north of London, there is a charming little stream called Mutton Brook that rises in East Finchley, flows under the Finchley Road at Henly’s Corner, then under the North Circular Road to meet Dollis Brook, which then becomes the River Brent and flows into The Welsh Harp. After a circuitous course through Wembley and Greenford, it enters the Thames at Brentford. The River Lea is the largest tributary of the Thames around the capital and is classified as a chalk stream, as it originates in the Chiltern Hills near Luton. The master wood-engraver Robert Gibbons, already famous for his Sweet Thames Run Softly in 1940, wrote and illustrated Lovely is the Lea in 1945, with some exquisite engravings of the natural world.
In 2005, and again in 2011, a 15lb Canada goose was pulled down very quickly by a large predator, according to witnesses, going ‘vertically down’ in the space of half a second. It seemed unlikely that a pike could be capable to take such a prey, so speculation about what it was ranged from a caiman, a crocodile, a snapping turtle, or, more likely, a wels catfish, but British Waterways strenuously denied that there might be a crocodile in the river.
These rivers not only provided water for the expanding capital, they powered dozens of water mills, with more than thirty on the Wandle alone: tobacco-mills, snuff-mills, copper-mills, oil-mills, leather-mills, flour-mills, a parchment-mill and at least two paper-mills. Cutlers, dyers, tanners and, of course, brewers, all needed water and power to produce their goods. Other hidden rivers include the Falcon in Clapham, the Effra, flowing through Brixton, the Peck sourcing in Dulwich and Counters Creek flowing through Chelsea, but, in the past, they were part of daily life, until urbanisation obliterated all but a handful. As Ella Fitzgerald sang, ‘Fish got to swim, birds gotta fly.’ And rivers got to flow.