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Title: Clear Options towards an operational model for the Lee Valley Reservoirs
Author: Freshwater Biological Association
Document Type: Monograph
This report seeks (i) to assess, largely in qualitative terms, the likely impact of the broad strategy for supplying London's water upon the treatment capacity of the Coppermills WTW and (ii) to make a preliminary evaluation of the various options for operating the Lee Valley reservoirs so as to minimise that impact as far as possible. In the present context, the efficiency of WTW performance is assumed to be judged principally in terms of operational outputs and of the frequency with which slow-sand filters require to be cleaned. In turn, the concept of quality will refer mainly to the amounts of filterable material delivered to the treatment works per unit time; for practical purposes 'filterable material' is, in most instances, that dominated by planktonic algae present in the water initially drawn from the fluvial resources (R. Lee, R. Thames), subject to such increase by self-replication as may have occurred within the intermediate storage reservoirs. There are other quality criteria, including the content of suspended non-living particulates, dissolved chemicals and pathogenic bacteria. Besides maintaining a reserve capacity for such times that river resources are low or of poor quality and water demand is high, storage reservoirs furnish an important step in the preliminary treatment of the raw river water and simultaneously provide a buffer against the direct passage of pollutants or pathogens into the supply system. Thus, these counterposed disadvantages and benefits of the storage reservoir must be balanced in order to optimise the quality of the water delivered to the treatment work.
Publisher: Freshwater Biological Association
Publication Date: 1988
Publication Place: Ambleside
Subject Keywords: Wastewater treatmentFiltersFiltrationAlgaeSuspended solidsWater abstractionChemical compositionChlorophyll aWater resources
Geographic Keywords: ThamesLee (Hertford)
Extent: 30
Total file downloads: 24

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