River Boyne Water Quality Management Plan - EPA

River Boync WarcrQuality hlanagamenl PlanThis is funher classified in 4 general pollution classes as follows:-Biotic IndexQuality StatusClassification..........................................Q5,Q4-SjQ4...... 43-4"..............."Q3,QZ-3Q2, Qla.QI".....".............................................................................................Unpolluted WaterClass A..................................................................................................................................................................Slightly Polluted WaterClass B.........................................................Moderately Pollutcd WaterSeriously Polluted WaterBiotic indices, therefore, are used to determine water quality status as regards organic pollution. Theyare not designed to detect toxic pollution and should therefore be combined with physico-chemicalassessment of the water column and bed sediments. Since most of the pollution occurring in Irishrivers is organic, the use of a biotic index provides a useful method of interpreting the significance ofthe invertebrate communities in terms of water quality.The EPA survey method involves complete assessment of the site in the field, including ascribing aQ-Value. Preference is given to riffled sites with turbulent flow conditions and hand-net sampling iscarried out according to IS0 standard 7828-1985 (McGarrigle et.al. 1991). This involves kicksampling for 2-5 minutes with a similar period spent picking animals from stones to ensure that thosewith sufficient holdfast mechanisms are included in the sample.The sample is transferred to a tray and a field inventory of the ia%rtebrates is made on site. Thegeneral conditions such as botton substratum, velocity, clarity, &fsence or absence of sewage fungus,macrophytes or algae are also recorded. The data is the~&d&ensed into a 5 point biotic index of Q-value, which is interpreted as follows:-Class A waters are considered unpolluted and cqoq garded as satisfactory. Water classified as Band C are likely to have an adverse effect o+$&rtctal uses to a lesser or greater extent. Class Dwaters are ser.iously polluted and may be ina$'@le of sustaining aquatic life.'q~'.-+i.C\5.2.1 Biological Assessment of Boyn@iver System.* .For inspection purposes only.Consent of copyright owner required for any other use." "Class C--Class DThe site locations where biologicatFhonttoring of the RiverBoyne is carried out in the catchment areshown in Map No.9 and the data is summarised in Table 5.2a for stations on the main river channel.Fig. 5A and 5B are extracted from the ERU Reports (1991 and 1995) entitled "Ireland - RiverQuality". In this map, blue signifies unpolluted (Class A), green signifies slightly polluted (Class B),brown signifies moderately polluted (Class C) and red signifies seriously polluted (Class D). Table5.2 gives historical data for the Boyne River and more recent 1994 data.An overview of the Boyne catchment for 1994 data (Tables 5.2) indicates the following:-* The main River Boyne channel is relatively unpollzitedfromSlane to Drogheda and upstreamof the Stonestown River tributary. The Kells Blackwater is of similar qualily in its lowerreaches, as is the Stonyford River and Lough LeneRivers indicated as slightlypolluted include the Boyne channel upstream of Sla~ze to zrpshearnof Trim, the Moynalty River, /he Athboy and Deel Rivers, the Yellow River and thedownstreani sectio~i of the River Blackwnler (Longwood)EPA Export 26-07-2013:17:27:00