River Boyne Water Quality Management Plan - EPA

2.5 LakesLakes within a river system require particular attention in the context of water resourcesmanagement. By virtue of the storage which they provide, they have greater potential to meet waterabstraction requirements. At the same time, the long average residence time results in a complex ecosystemwhich is sensitive to environmental pressures such as organic pollution and nutrientenrichment (phosphates and nitrates).Table 2.6 is a list of lakes within the Boyne catchment. Table 2.7 summarises the lakes for whichdetailed information is available on contributing catchment area, lake surface area, stored volume,mean and maximum depth and water residence time. These parameters provide a basis for assessingthe lakes from the point of view of potential abstraction yield and likely impact of organic or nutrientloadings.The table indicates the more significant lakes as follows:-e Lough Ramor in Co. CavanLough Lene in Co. WestmeathLough Bane in Co. Westmearh (34%) and Co. Mealh (67%)>+,.\.Ngcli-esgeel Loughs in Co. CavanSkragh Lo~rgA in Co. CavanCustle Lake in Co. Cava17Drun~kee~y Lake in Co. CavonLisgrea Loke in Co. Cavani~*.*For inspection purposes only.Consent of copyright owner required for any other use.The lakes provide a valuable angling resource, particularly for Co. Cavan with significant economicgain in the local areas. The majority of the lakes provide good course angling, with the foregoinglakes being the more notable. Significant lakes from a water abstraction point of view are.LoughLene, Skeagh Lough, Nadreegeel Lough, Lough Acurry, Drumkeery Lough and Cuilcagh Lough.Water quality data in lakes shows that, while generally satisfactory, the majority show evidence ofnutrient enrichment, leading to varying degrees of eutrophication. This involves excessive growth ofplants and planktonic algae. It causes fluctuation in dissolved oxygen (D.O.), pH and turbidity (waterclarity) and can render the water less suitable for abstraction, fish life and other beneficial uses.EPA Export 26-07-2013:17:27:00