EPA - Ireland's Environment, An Integrated Assessment - 2020

Ireland’s Environment – An Integrated Assessment 2020 Table 7.1  Surface water bodies with bad ecological status, 2013-2018 (Source: EPA) WATER BODY ECOLOGICAL STATUS COUNTY Rivers Avoca (two sections) Bad Wicklow Aughboy Bad Wexford Ahavarraga stream Bad Limerick Kilmihil stream Bad Clare Kilgolgan Bad Galway Owenriff Bad Galway Ballaghdoo Bad Donegal Roechrow Bad Donegal Lakes Lough Alewnaghta Bad Clare and Galway Ballyquirke lough Bad Galway Corglass lough Bad Cavan Lough Egish Bad Monaghan Lickeen lough Bad Clare Lough Macnean Lower Bad Cavan and Fermanagh Lough Muckno or Blayney Bad Monaghan Lough Naglack Bad Monaghan Rinn lough Bad Leitrim Templehouse Bad Sligo Urlaur Bad Mayo Estuaries and lagoons Lough Donnell Bad Clare Cuskinny lake Bad Cork Kilkerran lake Bad Cork Rogerstown estuary Bad Dublin Lady’s Island lake Bad Wexford Ballyteige channels Bad Wexford Rincarna pools Bad Galway The number of bad-status water bodies (the worst of the worst) has fallen marginally over each assessment period, but there are still 27 water bodies in the most polluted category. These include nine rivers, 11 lakes and seven estuarine water bodies (Table 7.1). This classification means that these water bodies are being severely damaged by pollution and other human disturbance to an extent that prevents them from supporting most types of aquatic life. At the other end of the scale our best-quality, least-polluted and least impacted, high status waters are important reservoirs of aquatic biodiversity. These waters provide a home for species sensitive to pollution including river insects such as stoneflies and mayflies and the young and larval stages of salmon and trout. Their loss is a significant concern. The proportion of high-quality sites (Q5, Q4-5) has almost halved since the late 1980s declining from 31.6 per cent of rivers in 1987-1990 to just 17.2 per cent in 2013-2018 (Figure 7.6). Even more worrying is the dramatic reduction in the number of our most pristine rivers – the best of the best (Q5) – which has fallen from 573 sites to only 20 sites over the same period. A macroalgal bloom in Rogerstown Estuary, Co. Dublin. These blooms can form extensive dense mats which can smother other animals in the sediments below them. 166