River Boyne Water Quality Management Plan - EPA

River Blnckwnter (KeNs) ; /his river is shown as gross1.v polluted in it's upper reaches,improisirig to slightly polluted/moderately polluted in the niiddle reaches and relativelyunpollirted in it's lower reaches. Overall, rhe middle and lower reaches of the river haveslightly disinproved over time up to 1994River Devlin ; data on this river shows it to be slightly polluted and soniewhatdisimprovedfrom (he mid-1980'sDrunlkeery Lough Stream ; this is indicated as nioderatelypoll~rted improved since 1990Lislen River ; indicated as unpolluted with no change recentlyMattock River ; the Mattock River is indicated as slightly polluted to un-pollzrted over it'slength, which is an improvement over the years0 Moynal@ River ; this river is generally slightly polluted with a local black spot on the ChapelLake branchThis biological data on the River Boyne system provides an overview of the water qualityenvironment. It indicates a reasonably satisfactory situation over;~@'in the catchment, with a numberof remaining black spots and with indications of an increase i&he extent of slightly to moderatelypolluted river. This is almost certainly associated ..,:"@$utrophication arising from nutrientenrichment.,.., >-Biological rating is an essential part of water ~$&l& assessment, providing a reliable indicator ofgeneral quality and change over time. It is p&~@farly useful in assessing the culnulative impact ofgeneral pollvtion or occasional discharges *'&'may not be identified in periodic water sampling. A\ :c