117 research outputs found
Hydrological changes and river regulation in the UK
No full textWater levels of streams and rivers in the United Kingdom have been regulated by weirs for more than one thousand years, but regulation of the flow regime by impoundments began in the latter half on the 19th Century. Organized river flow measurements were not undertaken until 1935, and today the average record length is about 20 years. Only three gauging stations have provided data suitable for pre- and post-impoundment comparisons. Other studies have relied on the comparison of regulated and naturalized discharges. In either case climate and land-use changes make evaluation of the hydrological effect of impoundments problematic. This paper reviews research on hydrological changes due to river regulation in the UK, and presents a case study of the River Severn to evaluate the influence of Clywedog Reservoir on flood magnitude and frequency.
Consequent upon dam completion, on average, median flows have been reduced by about 50per cent; mean annual floods have been reduced by about 30per cent; and low flows have been maintained at about 22 per cent higher than the natural Q95 discharge. However, marked differences exist between rivers. The direct effect of reservoir compensation flows and the indirect effect of inter basin transfers for supply have significantly increased minimum flows in most rivers, although in the case of the latter this involves the discharge of treated effluents. In contrast, the effects of impoundments on flood magnitude and frequency is less clear and on the River Severn, at least, changes in flood hydrology during the past two decades are shown to be more related to climate change than to river regulation
Professor Geoffrey Petts (1953-2018): An outstanding interdisciplinary river scientist
No full textThis paper provides an introduction and an editorial to this special issue of River Research and Applications by documenting the contributions made by Professor Geoffrey Petts to our interdisciplinary understanding of the functioning of rivers and their floodplains and their sustainable management. We outline Geoff’s career, which framed not only his research but its communication through his inspirational teaching but also included very high level and innovative contributions to the management and development of several UK universities. We then explain how and why Geoff was an outstanding interdisciplinary river scientist and how he communicated his science through both integrative books and book chapters and also research papers that developed eight complementary research themes. Lastly we introduce the papers in this special issue and show how they provide inputs to all eight of Geoff’s areas of research interest
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