The rivers of a riverless city: An ode to Birmingham

UK Topographic Map
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One of the often quoted facts about the city of Birmingham is that it has “more miles of canals than Venice” although as others have pointed out before, that fact somewhat misses the point. It’s somewhat disingenuous in any case as Birmingham is much bigger than Venice (thus has a lower density of canal) and there are other cities (such as Amsterdam) who can make similar claims. A far more fascinating fact from a river management point of view is that Birmingham doesn’t really have any rivers.

Birmingham has three named water courses flowing through it: the River Cole, River Tame and River Rea. At the point they flow through Birmingham none of these rivers is large enough or deep enough to be navigable by any boat of a reasonable size (i.e. by nothing much larger than a canoe). I believe this makes Birmingham almost unique as a temperate large metropolitan area without a port or a navigable river (along with its West Midlands cousin Coventry), although am happy to be proved wrong (in the comments please!) My criteria are the region the city is in has to be temperate (so arid cities don’t really count, although I’d be happy to have examples), and the city has neither a lake or sea port or a river capable of taking boats at any part of the year – get thinking!

The motorways around Birmingham, where the M5 and southern part of the M42 mark the approximate boundary of River Humber and Seven catchments

However despite it’s position as an almost riverless city Birmingham has a lot to interest the river manager and catchment hydrologist. The reason for this is Birmingham is one of the highest cities in the UK at an average of 130m above sea level and straddles the boundaries of two of the UK’s great watersheds. Very roughly speaking the M5 and M42 motorways are the boundaries between the catchments of the River Trent (central Birmingham) and the River Stour (The Black Country).

Thus a drop of rain falling within the Woodgate Valley Country park, to the West of the city will eventually make its way East via the Bourn Brook, past the University of Birmingham campus, into the River Rea in Cannon Hill Park (a river so degraded it had the lowest ecological status of “poor” in 2009!), through and under the city centre before meeting the River Tame under junction 6 of the M6 (“Spaghetti Junction“). From there it makes its way North and meets the River Trent north of Lichfield and flows past Nottingham, Newark and meets the Humber between Goole and Hull and eventually out into the North Sea via the Humber Estuary.

Map showing major river areas of UK with River Humber highlighted in blue (www.wfduk.org)

Conversely a drop of rain falling just slightly to the West of the Woodgate Valley park, would makes its way via one of the small tributaries of the East Stour just South of Halesowen, past the ruined Abbey and into the River Stour proper where it would flow through Dudley, Stourbridge and Kidderminster before meeting the River Severn at Stourport-on-Severn. It then flows via Worcester and Gloucester and out into the Bristol Channel.

So a rain shower to the West of Birmingham will see some rainwater flow eventually into the North Sea and some, falling just a few hundred metres away, flowing into the Bristol Channel, over 200 miles from the Humber Estuary.

Although it has no large river flowing through its centre, Birmingham’s position at a high point on the boundary between two of the great river catchments in the UK makes it interesting and important from a hydrological perspective. With regards to the water framework directive combating the degraded quality of some of the small streams and rivers in and around Birmingham, particularly diffuse pollution, can have a knock on effect upon water quality and ecology within the Trent and Stour and thus the Humber and Severn. Given the large population and the lack of a large river to discharge treated waste water into, water treatment in Birmingham has to embrace new technology to ensure the effluent they discharge is as clean as possible. Although many people may not want to think about it waste water treatment discharge operates to a degree on the principle of dilution! This means if one is discharging effluent directly into the Seven or Thames a less clean discharge will be quickly diluted within the large discharge of the river to minute concentrations, which is not the case if it is discharged to a small river.

This illustrates that even a city without a river needs to be considered as part of a catchment wide approach to river management.

Don’t forget to post your examples of other big cities with neither large rivers or ports (lake or sea) in the comments.