River Boyne Water Quality Management Plan - EPA

River Boync Water Qualiiy Managemm1 PlanThe foregoing dissolved oxygen profile in the River Boyne system shows general compliance, withsome critically low readings in sections of the river system for critical conditions (low river flows,high summer temperatures and growth conditions). Data for the Yellow, Castlejordan, Deel andKnightsbrook rivers, shows satisfactory D.O. levels with rare values below 7 mgll. The critical areaslisted above are consistent with those river sections with inferior biological status, as outlined insection 5.2. The key issues adversely affecting D.O. levels are;Limiting organic loadingControl of nutrierits to lir~iitplant and algal growth, partictrlarly in slowjlowing rivers.5.3.2 Bioclremical Oxygen Demand (BODg)Biochemicnl oxygen demand (BOD5) is the accepted measure of biodegradable organic matterpresent in the water, with a limiting value of 5mgll 02 required in thesalmonid Waters Regulations(S1 293, 1988). Any values over 4 mgll 02 are borderline and indicate significant waste loads in theriver.In the upper Boyne catchment, values in excess of this limit have been noted as follows:River Boyne Upstreanr; Cliannel near Ederiderw i~idicafe~%ccosional high values (-1-3 mg/l),R3. $,.* Upper Boyne Tributaries; Locally on the rivers &h,Deel, Kinnegad, Kriightsbrook, Skone07 ,XL ' . .arid Yello11. -07: .c&\ ++.h..'River Boyne Downsfreant; ~ccasion~$~& t~nlues ore recorded at Bective, npproaching 51 . Values afj.6 riig/l are reph&$l at Bellinfer on successive dws in Jnntra~y, 1993.Occosio~ial high valtres ore re@f&i?downstreani at Broadboyne arid Slane, presuniab!~related to the Nuvan Wastelc~nter0&scharge (> 5 nig/l02)A-L.River Blackwater (~ells);&; linrir valzres have been found fo be exceeded in the regionupstream of Lotrgh Ramor, with a number of exceedences don~nstreani of the lake oictlet.Occasionally exceedence of the li~iiit value (5 nig/l O2/ is indicated in Appendix 3 atBloomsbuy Bridge, Carnaross, Doriagh Patrick Bridge, Liscarton arid Mabes BridgeRiver Devlin; the li111it value of 51ng/l was exceeded in the zipper region of Sally gardens midaf Grange Crossroads (June 1995): otherwise the values in this river appear reasonableRiver Clady ; a number of high values have been recorded at T~rllaghansfown (1993/1994)River Mattock; reasonable vollres have been recorded apartfrom one exceedence at Boyd'sbridge (Mcy 1991) and New Bridge (May 1994)Moynalw River; Significant exceedence of the limit values hove been identified on this river,indicating excessive organic poll~rtion in the tipper reaches where values ore high withoccasianol breaches of the liniit-0'For inspection purposes only.Consent of copyright owner required for any other use.EPA Export 26-07-2013:17:27:01