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Title: Report for Anglian Water, NRA Unit on the inclusion of storm water overflows into the Orwell Estuary model, and its use to predict limits for SWO discharges
Author: C.J. Penney
Document Type: Monograph
The mathematical model of the Orwell Estuary has been amended to include storm water overflows. A WASSP analysis of the Idswich Borough Council Sewer system model was run by WRc for the first 26 storm in the Times Series Rainfall. The data on storm water overflows was summarised to calculate their effect on predicted estuary water quality. The Orwell Estuary model predicts that the rehabilitated sewer system will cause unacceptable conditions in the top segments of the estuary when all the other discharges meet proposed long term consent limits. Various options are proposed that the model predicts would achieve acceptable conditions by reducing the predicted 99 percentile B.O.D levels to 12 mg/1 or below, the MAC value suggested for transient pollution. The suggested level of discharge and number of times a discharge can occur per year are summarised in Table 7.
Publisher: National Rivers Authority
Publication Date: 1969
Publication Place: Peterborough
Subject Keywords: Pollutant loadMathematical modelsEstuariesSewage
Geographic Keywords: Orwell EstuarySuffolkEast Suffolk catchment
Extent: 26
Total file downloads: 269

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