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Title: The Influence of Variations in Flow on General Quality Assessment of Rivers
Author: J Ellis
Author: D Hunt
Author: Environment Agency
Document Type: Monograph
Annotation: Environment Agency Project ID:EAPRJOUT_1616, Representation ID: 17, Object ID: 1350; A summary document can be found at:
The Environment Agency monitors river quality mainly through spot sample analyses of Biochemical Oxygen Demand (BOD), ammonia and Dissolved Oxygen (DO). The resulting data is used for chemical classification according to the General Quality Assessment (GQA). The Agency needs to comment on changes in GQA results: these may occur for many reasons, but flow variations were thought to have a large impact. However, with no formal method to quantify the effect, the Agency has had to rely on the observations and experience of its regional staff. It therefore commissioned WRc plc to undertake a statistical study of the relationship between flow and various measures of water quality, including GQA class in particular. This report describes the methodology adopted and the results obtained from that study.
Publisher: Environment Agency
Subject Keywords: RiversWater qualityEnvironmental managementRegulationsWater levelsFlow rateMethodologyFreshwater ecology
Extent: 105
Total file downloads: 26

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