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Title: A Status Report on the Direct Oxygenation of the Tywi Estuary - October 1989
Author: S.P. Halfacree
Document Type: Monograph
Investigations into the well documented oxygen depletion problem in the Tywi estuary have continued during 1989. Continuous monitoring at four sites supported by boat surveys, has shown dissolved oxygen sags similar to those observed in previous years. Dissolved oxygen minima approached 1 mg/l for short periods. As has been observed in previous years, marine and estuarine algal blooms had a significant influence on estuarine water quality. Localised dissolved oxygen depletion occurs in the vicinity of Parc-y-Splotts STV, under freshwater flows, but only during neap tides. Even in the adverse conditions of the summer of 1989, when flows were low for a prolonged period and water temperatures were high, there was no evidence of fish mortalities in the estuary in spite of intensive fieldwork being undertaken by NRA personnel. The 2 tonne per day oxygenation plant has been poorly maintained and evaluation of the technique of direct oxygenation has been impossible this year. A 12 tonne per day unit is due to be installed on the estuary as a result of an agreement between the NRA and Velsh Vater pic. Calculations suggest that the 12 tonne per day plant may be of inadequate capacity due to the magnitude of the tidal flow in this estuary.
Publisher: National Rivers Authority
Publication Date: 1990
Publication Place: Cardiff
Subject Keywords: EstuariesWater qualityOxygenImprovementProjectsProject evaluation
Geographic Keywords: WalesLoughor to Taf catchment
Extent: n.p. [41]
Total file downloads: 308

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