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Title: Environmental impact of hypolimnial releases from Llyn Brianne
Author: R. Wightman
Author: S. Halfacree
Author: F. Jones
Author: D. Clarke
Document Type: Monograph
Following a public enquiry in December 1966, the West Glamorgan Water (Llyn Brianne) Order of 1968 authorised the construction of Llyn Brianne reservoir in the R. Tywi upstream of Llandovery. Widespread public concern has subsequently been expressed regarding release into the river of water drawn from the hypolimnion of the reservoir. This concern is principally related to the effect of the reservoir on the thermal regime in the river. This paper has the following objectives: (i) To review existing evidence of ecological and fishery impact downstream of Llyn Brianne; (ii) To assess the cause and extent of such impact; (iii) To evaluate the requirement for installation of a multiple level release system.
Publisher: National Rivers Authority
Publication Date: 1990
Publication Place: Cardiff
Subject Keywords: RiversThermal controlWater reservoirsWater transferWater temperatureEnvironmental impactEcologyFisheries
Geographic Keywords: WalesLoughor to Taf catchment
Extent: n.p. [34]
Total file downloads: 315

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