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Title: Biological investigation into the impact of the storm overflow at Middle Marwood Sewage Treatment Works
Author: S. Hunter
Document Type: Monograph
Annotation: EA additional title info: DEV/EP/12/99 (Catchment 30A)
Middle Marwood Sewage Treatment Works has an embargo, preventing any further connections to the works. The storm overflow reportedly operates almost continuously with a significant proportion of the flow not receiving any biological treatment. In September 1998 a request was received from Environment Protection to undertake a biological impact assessment at this location. The aim of this investigation is to look at the impact of the storm overflow (subsequent to the start of the survey the storm overflow was found to be discharging at two discrete points) individually and in combination with the final effluent on the macroinvertebrate population in Marwood Stream. The final effluent is discharged down stream of the storm overflows. Our impact on the biodiversity of the site was taken into account during the planning of this investigation. Conservation were contacted in an effort to identify any sites recognised or designated as sensitive at or in the vicinity of Middle Marwood STW. Marwood Stream has a River Ecosystem Use Class of 2 (RE2). The stream is a tributary of Knowl Water, which has marginally failed its River Quality Objective of RE2.
Publisher: Environment Agency
Publication Date: 1999
Publication Place: Exeter
Subject Keywords: StormsWater qualityBiological surveysEnvironmental impact assessmentSewage treatmentBiodiversityRiversBMWP
Geographic Keywords: Marwood (Devon)
Extent: 19
Total file downloads: 303

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