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Title: An investigation into the effects of Alton sewage works on the River Wey North
Author: P. Greaves
Document Type: Monograph
During the late summer and early autumn of 1991, the water quality in the upper reaches of the river Wey North, which is normally of very high quality, deteriorated significantly causing fish mortalities in the stretch used for game fishing, and RQO failures. The deterioration in quality was due to Alton Sewage Works, which is operated by Thames Water Utilities, discharging an effluent into the river that at times breached the consent standards by a large margin. However, most of the time during the period in question, the effluent complied with the consent, but was significantly worse than that normally produced. Under these circumstances, this still caused severe water quality problems in the river downstream. This stretch of the River Wey normally poses no water quality problems such as these, and complies with the IB RQO. This is because the effluent produced by Alton sewage works, which is the key to high water quality in this stretch, is normally very much better than the consent requires. A drop in quality from the works, although remaining within consent, can produce severe problems in the river. If the water quality in the upper reaches of the Wey North is to be maintained, the consent for Alton sewage works needs to be tightened.
Publisher: National Rivers Authority
Publication Date: 1992
Publication Place: Guildford
Subject Keywords: SewageWater qualityEffluentsRivers
Geographic Keywords: Wey (Surrey)Wey catchmentSurrey
Extent: 12; + appendices
Total file downloads: 337

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