Epilithic diatom communities of Milltown Lake's catchment, Co. Monaghan, Ireland

The National Source Protection Pilot Project based at Milltown Lake, Co. Monaghan, is the first catchment-based source protection project established for the protection of drinking water sources in Ireland. Churchill and Oram Group Water Scheme extract their water supply from Milltown Lake, and preliminary results indicate that the lake is of eutrophic status, as categorised by the Organisation for Economic Co-operation and Development (OECD 1982) classification system. Phase one o f the project involves a detailed baseline water quality survey o f Milltown Lake 's catchment, in which this sub-project forms an essential role. Different biotic groups respond to different environmental factors (PAAVOLA et al. 2003); therefore, epilithic diatoms, in conjunction with macroinvertebrates and macrophytes in other sub-projects, are being studied to furnish the project with an assessment based on a number of taxonomic groups. This will establish the current status ofthe catchment and describe the composition of the diatom communities for future comparisons.