![]() ![]() ![]() LIDAR (a satellite derived map of land level) revealed a bit more information: in the image below you can see a darker line meandering down the valley, sometimes north, sometimes south of the straight ditched course of the river. Natural meanders on the River Tatīut we had to dig deeper than maps to find out what the river may once have looked like and also where it once flowed. More indicative were the more continuous meanders on the nearby Upper Tat, an almost identical size and type of stream. These, however, give an idea of the meander pattern the river once had. The entire upper river has been straightened and only in a very few places can relic meander sequences can be found: There’s a relic meander in the wood in the centre of the map: only a handful of these exist on the entire upper river. Only here we had no relic channel to restore, and not much in the way of reference reaches to use as a model. So, this project, like the one I described in my previous blog, was also aimed at re-meandering a much canalised river, this time in the headwaters. The straight channel was progressively made deeper by maintenance dredging through the 20th Century until the upper quarter of this Norfolk chalk-stream had become more of a drainage ditch than a stream. It seems as if the river meandered in 1797, but was dead straight within fifty years, when the first OS series was drawn. You have to go back to Faden’s map of Norfolk to find the upper River Nar drawn with a wiggly line. The second in my mini-series on our (Norfolk Rivers Trust) 2014 river restoration projects begins in the headwaters of the River Nar. It is available to view here: Restoration Drama Continuedįrom Faden’s 1797 map of Norfolk showing a meandering upper River Nar To make sense of the lay-out, please read the notes on the lay-out at the head of the index. ![]() In the meanwhile, I hope this index proves a useful resource for those who are interested in the conservation of English chalk-streams. Already I have been promised updates for Buckinghamshire! Please send feedback to me at the contact email on this blog and I will include corrections and additions and credit the contributors. In time I will work this index into a series of catchment-based maps, which will include those geological sub-categorisations on which Haydon and I will do more work. I worked on this index with Dr Haydon Bailey, a geologist with a keen interest in chalk, and we have started to sketch out some geological categorisations that help to shed light on those differences and show that what we have, in reality, is a spectrum of pure chalk-streams and chalk-influenced rivers. Chalk-streams are created by geology, the geology of England is complex and chalk-streams vary so much in character. I’m often asked “What is a chalk-stream?” It is a difficult question to answer quickly. I recently compiled my best attempt at a complete index of all the English chalk-streams, partly to satisfy my own cataloguing obsession, partly because it was needed for WWF’s new report State of England’s Chalk-Streams 2014. ![]()
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