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Title: Quantification of the relationship between effluent quality and biological quality : interim report for stage 1
Author: A. Gunby
Author: I. Milne
Author: M. Wheeler
Document Type: Monograph
Annotation: EA additional title info: regional operational investigation 579 - quantification of the relationship between effluent quality and biological quality
This Interim Report is the first formal output from Regional Operational Investigation 579, to quantify the relationship between effluent quality and the biological quality of rivers. This investigation was initiated to address the need to develop a methodology for relating sewage treatment works effluent quality to biologically assessed water quality. Procedures already exist within NRA Anglian Region for identifying STW effluents with the greatest potential impact in terms of chemical quality. This takes the form of the Index of Discharge Impact, which is calculated from the statistics of compliance with the River Needs Consent and from an assessment of compliance of receiving waters with quality standards. The RNC is a working estimate of the consent that may be needed in future to achieve Water Quality Objectives. The IDI is used to prioritise discharges for targeting for improvement and the ability to link biological data in with the assessment would substantially enhance confidence in the methodology, hence the inception of this project.
Publisher: National Rivers Authority
Publication Date: 1996
Publication Place: Peterborough
Subject Keywords: EffluentsSewage treatmentWater qualityWater quality measurementsBiological analysisData
Geographic Keywords: EA Anglian
Extent: 45
Total file downloads: 285

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