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Title: An ecological study of the effects of ferric dosing on the plankton and benthic invertebrates of Grafham Water between May 1990 and November 1991
Author: National Rivers Authority Anglian Region
Document Type: Monograph
Since July 1990, ferric sulphate dosing of Grafham Water Reservoir has been carried out by Anglian Water as part of a strategy to lower phosphate levels and thereby reduce the incidence of blue-green algae blooms. In 1990 dosing was carried out by a combination of methods discharge from the draw off tower discharge from the aeration tower and from a barge. In 1991 dosing was carried out almost entirely from the aeration tower. Substantial quantities of ferric sulphate have been used. During 1991, up to 2,500 tonnes per month were being discharged, with a total of around 25,000 tonnes for the year up to September 1991. The ferric sulphate being in an 11% solution as iron. The National Rivers Authority has carried out biological monitoring over this time to assess any effects of the dosing programme on the plankton and on the benthic invertebrates of the reservoir.
Publisher: National Rivers Authority
Publication Date: 1992
Publication Place: Peterborough
Subject Keywords: Cyanophyceae; Water reservoirs; Benthic environment; Benthos; Invertebrates; Zooplankton; Phytoplankton; Phosphates; Sulphates; Biological monitoring
Geographic Keywords: Grafham Water; Cambridgeshire
Extent: 5; + figures and tables
Total file downloads: 0

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