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Title: Impact assessment of Helston Sewage Treatment Works on water quality of the River Cober Loe Pool
Author: S. Smith
Author: L. White
Document Type: Monograph
Annotation: EA additional title info: environmental protection report
The National Rivers Authority South-West (NRA SW) has expressed concern over the contribution of Helston Sewage Treatment Works (STW) to poor water quality in the River Cober and Loe Pool. Therefore, a study of recent water quality data collected at routine monitoring sites was undertaken to determine the extent of inqpact. Poor final effluent quality from Helston STW resulted in an increase in BOD and total ammonia concentrations in the River Cober during a rainfall event in October 1989. This caused river water quality standards to be exceeded. However, since 1989 monitored water quality has not exceeded river quality standards. Non-compliance with river quality standards occurred at Loe Pool outfall during 1989 and 1990 and was attributed to presence of severe algal blooms in Loe Pool. The final effluent from Helston STW could be the principle source of nutrient enrichment to Loe Pool and therefore the principal cause of algal blooms. It is recommended that the River Cober and the final effluent at Helston STW are monitored during heavy rainfall to determine the current impact of Helston STW on the River Cober under these conditions.
Publisher: National Rivers Authority
Publication Date: 1992
Publication Place: Exeter
Subject Keywords: RiversLakesWater qualityEnvironmental impact assessmentSewage treatmentAmmoniaDissolved oxygen
Geographic Keywords: EA South WestWest Cornwall and the Fal catchmentCornwall
Extent: 7; + figures and appendices
Total file downloads: 71

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