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Title: Time of travel of pollutants study : River Torridge : Q28/Q32
Author: National Rivers Authority South Western Region
Document Type: Monograph
Oscar Faber Water was commissioned by the National Rivers Authority, South Western Region, to undertake a study of the time of travel of pollutants in the River Torridge between Black Torrington Bridge and Old Rothem Bridge, during high flow conditions. The study was carried out over the period 14th to the 15th December 1994. The river was divided into six reaches and these were studied in succession in an upstream direction using Rhodamine-B as the tracer. Average daily flow reduced gradually during the study period from a Q28 percentile (Torrington gauge, 16,730 m3/s) to a Q32 percentile (Tonington gauge, 14.324 m3/s). The combined time of travel for the overall distance of 40.550 km for Black Torrington Bridge to Old Rothem Bridge, was 16 hours 35 minutes. The average velocity of travel was 0.68 m/s.
Publisher: National Rivers Authority
Publication Date: 1995
Publication Place: Exeter
Subject Keywords: RiversWater pollutionTimeFlow rate
Geographic Keywords: EA South WestTorridgeNorth Devon catchment
Extent: 8; + appendices
Total file downloads: 279

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