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Title: Investigation into failures of the River Dalch from Canns Mill Bridge to below Lapford sewage treatment works (2001)
Author: S. Hunter
Document Type: Monograph
Annotation: EA additional title info: Devon Area internal report July 2001
The River Dalch significantly failed to meet its River Quality Objective (RQO) of RE2 (River Ecosystem use class), in 1997 and marginally failed in 1998. The failure was due to elevated Biochemical Oxygen Demand (BOD) and elevated ammonia in 1997, and elevated BOD in 1998 (Ref.1). Devon Area Investigations were asked to investigate the cause of the failure and make recommendations to improve water quality in the River Dalch. The River Dalch is a tributary of the River Yeo. It rises to the north of Puddington and flows in a south-westerly direction until its confluence with the River Yeo at Lapford. Lapford Sewage Treatment Works (STW) discharges into the Dalch approximately 300m above the confluence with the Yeo. The aim of this investigation is try and identify the causes of the failures in the stretch of the River Dalch and to make recommendations in an attempt to prevent further failures. It is suspected that the ponding effect of the weir combined with the final effluent discharge is having a deleterious effect on water quality. The investigation will aim to test this theory.
Publisher: Environment Agency
Publication Date: 2001
Publication Place: Exeter
Subject Keywords: River Quality ObjectivesWater qualityRiversEnvironmental qualityPollutant loadAmmoniaSewage treatmentWater quality surveysFlow rateWeirs
Geographic Keywords: Dalch (Devon)Yeo (Lapford)North Devon catchmentDevonLapford
Extent: 23
Total file downloads: 38

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