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

Chapter 7: Water Quality Of most concern is the continuing decline in high status water bodies and the increase in the number of water bodies in poor ecological health. The proportion of high status surface water bodies has decreased by one-third (94 water bodies) since the period 2007-2009, while the proportion of poor status surface water bodies increased by one-third (115 water bodies) over the same period (Figure 7.5). The loss of high status waters has implications for the survival of certain protected species sensitive to small changes in water quality such as the freshwater pearl mussel ( Margaritifera margaritifera ), while at the other end of the spectrum the ecology of poor status waters is so significantly altered that their ability to function normally in terms of food web dynamics and nutrient cycling is greatly diminished. The Laney river upstream of Macroom, Co. Cork. One of the few remaining highest quality (Q5) rivers Figure 7.5  Change in each of the five Water Framework Directive status categories over three assessment periods for all surface waters (number of water bodies in each class) (Source: EPA) 2013-2018 (2703) 2010-2015 (2693) 2007-2009 (2503) 0% 20% 40% 60% 80% 100% High Good Moderate Percentage (%) of surface water bodies Poor Bad 230 290 324 1196 1202 1096 765 718 678 485 454 370 27 29 35 Biological monitoring by the EPA on the River Dargle. 165