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Title: Combined sewer overflow remedial strategy : South West Area report
Author: National Rivers Authority Welsh Region
Document Type: Monograph
Annotation: EA additional title info: version 2 February 1995
Storm water overflows on sewerage systems are designed to reduce the capacity of combined or partially separated systems which would otherwise be required to carry excessive volumes of rainfall generated storm water. They act as release valves when the maximum sewerage capacity is reached during peak flow events and thus prevent flooding and damage to the sewerage system. The majority of Welsh sererage systems receive both surface water and sewage (as well as trade effluent in many cases), and storm overflows are therefore described as combined SewerOverflows or CSOs. In theory CSOs are designed to minimise the impact on the receiving watercourse by only discharging diluted sewage into rivers when their assimilative capacity has also been increased by a rainfall event. In practice these ideal criteria are not always met and grossly aesthetically polluting discharges do occur.
Publisher: National Rivers Authority
Publication Date: 1995
Publication Place: Cardiff
Subject Keywords: SewerageSurface waterRain water managementWater pollutionImprovement
Geographic Keywords: Wales
Extent: n.p. [95]
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