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Title: Porth stream EC surface water abstraction failure 1993 : final draft report
Author: Rob Hocking
Document Type: Monograph
Annotation: EA additional title info: environmental department cornwall area
The Porth Stream at R25A025 failed for colour in 1993. R25A025 is the abstraction point for Rialton Mill water treatment works (WTW). The locations of monitoring sites and summary of water quality data are shown in figure 1. The Porth Stream at R25 A025 exceeded the colour standard (twenty filtered hazen) three times in 1993. The Porth Stream at R25A031 and R25A030 exceeded the standard on three and five occasions respectively. However, these samples were taken on different dates from R25A025. Because R25A030 had colour failures in 1993 the investigation concentrated upstream of this point. Data from both 1993 and 1994 indicated that all failures were associated with rainfall either on the day of sampling or in the previous two days. Failures occurred any time during the year and were not linked with high chlorophyll concentrations in Porth Reservoir. Therefore, algal blooms are unlikely to contribute to failure. The Indian Queens bypass construction work was not isolated in the investigation because of the number of failures in the catchment before earthmoving began in the summer of 1993.
Publisher: National Rivers Authority
Publication Date: 1993
Publication Place: Exeter
Subject Keywords: StreamsWater abstractionWater resourcesWater qualityWater sampling
Geographic Keywords: CornwallNorth Cornwall, Seaton, Looe and Fowey catchment
Extent: n.p. [5]
Total file downloads: 13

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