Bathing Place at Portumna (2013)
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Bathing Water Profile - Bathing Place at Portumna (2013) Bathing Water: Bathing Place at Portumna Bathing Water Code: IESHBWL25_191a_0100 Local Authority: Galway County Council River Basin District: Shannon Monitoring Point: 185949E, 203493N 1. Profile Details: Profile Id: BWPR00159 Toilets Available: Yes Year Of Profile: 2013 Car Parking Available: Yes Year Of Identification 1992 Disabled Access: Yes Version Number: 1 First Aid Available: Yes Sensitive Area: Yes Dogs Allowed: Yes Lifesaving Facilities: Yes Figure 1: Bathing Water 2. Bathing Water Details: Map 1: Bathing Water Location & Extent Bathing Water location and Portumna Bathing Water is located in the Lough Derg Management Unit of the Shannon River Basin extent: District in County Galway. Portumna town is located on the N65 about 64km from Galway City and 57km from Athlone Town, Co. Westmeath. The bathing area is situated at the head of Lough Derg about 1.5km south of Portumna town centre. It may be accessed by taking the L4320 in the town centre beside the Bank of Ireland. Proceed through the next crossroads, then follow the L4321 which leads to the bathing area facility. The bathing water area is approximately 400 metres long with an area of 800m2. Main features of the Bathing Type of Bathing Water: The bathing water is situated at the northern end of the lake, a short distance Water: from where the River Shannon enters Lough Derg. It is a pleasant well maintained facility used throughout the year. It is situated in a shallow area of the lake between a small jetty on the west and a reed bed on the eastern end. There are also two small jettys leading out into the lake waters. The lake bed is a mixture of gravel, mud and sand. Fauna/Flora Riparian Zone: To the West of the bathing area is Portumna Forest Park and Portumna Castle Grounds. Vegetation is generally not present in the bathing area although, following poor weather conditions, Phragmite Reeds may be present in small numbers; however, it is unlikely to interfere with bathers. The underlying geology of the lake is carboniferous limestone and water transparency in the lake is medium. Surrounding the bathing area are amenity grounds composed of grassy areas, footpaths, planted trees, shrubs and flower beds. Some of the native trees present in the vicinity of the bathing area are Scots Pine (Pinus sylvestris), Birch (Betula spp.), Alder (Alnus spp.) and Ash (Fraxinus spp.). The land bordering the amenity area is a mixture of reed beds and marsh, agricultural land and forest. The lake is rated as nationally important for waterfowl. Species that may be present include Mute Swan (Cygnus olor), Mallard (Anas platytrhynchos), Golden Eye (Bucephala clangula), Coot (Fulca atra), Moor Hen (Gallinula chloropus), Tufted Duck (Aythya fuligula), Widgeon (Anas penelope) and Cormorant (Phalacrocorax carbo). Black Headed Gulls (Chroicocephalus ridibundus) and Pied Wagtail (Motacilla alba). Lough Derg is also of conservation interest for its fish and freshwater invertebrates and Lampreys (Petromyzonidae spp.), listed under Annex II of the EU Habitats Directive, are known to occur in the lake. Tidal Range/Water Depth: Portumna Bathing Area has a microtidal range (<2m) with a medium depth of 1 metre and a and a maximum depths of 3 metres. The lake is generally calm although it can be subject to strong wave action and currents. Land use: The land bordering the amenity area is a mixture of reed beds and marsh, agricultural land and forest. Visitor numbers: Max. number of visitor during a day in high season: 200 persons Main features of the Bathing Water: Approx number of visitor during the bathing season: avg no 50 * 90 days = 4500 Activities available at the The lake is suitable for sailing, windsurfing and canoeing and boats can be hired to explore the lake. It is Bathing Water: also a popular location for anglers (fishing permit required). Pony rides may also be available during the summer. An information board is also present. Contributing catchment Description of the Contributing Catchment: Portumna Bathing Water is located in the Lough Derg details: Management Unit of the Shannon River Basin District in County Galway. The catchment is extensive as it forms part of the Shannon catchment. Lough Derg, the lowest order lake on the River Shannon, is one of the largest bodies of freshwater in Ireland. It stretches 34.5km from Portumna at the northern end to Ballina/Killaloe situated at either side of the southern end. It has a surface area of 117km2 with an average depth of 7.5m. Topography: The northern portion of the lake is relatively shallow with a mean depth of 4m. The shore area is flat and there are extensive reed beds in the bays. The catchment area is surrounded mainly by improved pastoral farmland to the south and east with areas of bog to the southwest and west. Soils/Subsoils and Bedrock: The bedrock varies and includes muddy limestone and lime mudstone. The main subsoil in the area is till derived from limestone with rocky outcrops in areas. The vulnerability of the groundwater in the area varies near the bathing area from low to extreme. Rainfall: Average annual rainfall in the area is 1000 to 1200mm. Mean Rainfall at the nearest MET station in Gurteen during the period 1961 to 1990 was 860mm. The month with the highest mean precipitation during this period was December at 93 mm, while April had the lowest mean precipitation at 56 mm. However in 2010 the wettest month was July with 117mm of rain and the driest month was December with 24.6mm. This data indicates that there is a risk of unusual weather events which may contribute to a short-term pollution event. Land use: Forestry plantations are present along the west and north west shore. The land is generally low lying and is used predominately for cattle rearing and milk production as well as some tillage. Livestock and fertiliser usage within the catchment are in line with national averages. Formal Designations: Lough Derg is of significant ecological interest, with six habitats listed on Annex I of the E.U. Habitats Directive. The entire lake, including all islands, is also a designated SPA. Population centres: Portumna 1530 (CSO, 2011) Monitoring point details: The monitoring point is located centrally in the bathing area at E 185949 N 203493 Reason for selection of the It is considered to be a suitable location for determining the quality of the water within the bathing area. monitoring point: This monitoring point has been used historically. It is not considered that the water quality varies significantly throughout the identified bathing area. Water quality assessment: Based on the results obtained from 2006 to 2009, the classification under the Bathing Water Regulations, 2008 was determined as excellent for the four years. It should be noted, however, that there are spikes on occasion with elevated levels of faecal coliforms. The source of this contamination is unknown but it is suspected that it is linked to heavy rainfall events. Water Quality Results: The 95th percentile calculation for water quality classifies the bathing area as excellent and of a standard commensurate with that of a Blue Flag Beach for the period 2009-2012. 3. Identified Pressures: Map 2: Bathing Water Catchment 3.1 Potential pressures in the catchment assessed as posing no risk: Description: Section 16's Source: Pressure Posing No Risk Type: Industrial discharges Short Term Pressure: No Description: Portumna Waste Water Treatment Plant Source: Pressure Posing No Risk Type: Waste Water Treatment plant Short Term Pressure: No Description: Leisure Boats Source: Pressure Posing No Risk Type: Recreational boating and charter shipping Short Term Pressure: No 3.2 Potential pressures in the catchment assessed as posing risk: Description: Agriculture Source: Pressure Posing Risk Type: Run off from agricultural land Short Term Pressure: Yes Nature: Low Risk Frequency: unknown Duration: < 24 hours Risk Assessment Risk assessments were carried out in 2005 using EPA Diffuse Model and were reported as part of Methodology: the RBD plans. Risk Assessment Several catchments up-gradient of the bathing area were identified as being at risk from agricultural Results: activities. The likelihood or magnitude was not determined. Details: As detailed above, the water quality in the area is generally good; therefore, the risk of short term pollution is low. Management Measures: Investigative monitoring is carried out on a prioritised basis throughout the county. Due to the quality of the water in the area, this catchment is considered low priority. Description: On-Site Wastewater Treatment Plant Source: Pressure Posing Risk Type: Septic Tank Short Term Pressure: Yes Nature: Low Risk Frequency: unknown Duration: < 24 hours Risk Assessment All of the waterbodies in the catchment for this bathing area have been identified as being probably Methodology: at risk from on-site wastewater treatment systems Risk Assessment Risk assessments were carried out as part of the RBD plans. There are 14,643 septic tanks in the Results: Water Management Unit, 6,958 of these are located in areas of very high or extreme risk. The catchment for this bathing area forms a small part of the water management unit. Details: As detailed above, the water quality in the area is generally good, therefore the risk of short term pollution is low. Management Measures: The National Inspection Programme provides a mechanism for dealing with this issue; however, considerable resources are required to carry out inspections in any catchment. Inspections in the county will be carried out on a priority basis in line with available resources. Due to the quality of the water in the area, this catchment is considered low priority. 3.3 Other Risks: Assessment of the potential for proliferation The Lough Derg Water Management Unit Action Plan states that Lough Derg has a moderate of cyanobacteria: water quality based on a mesotrophic rating in 2004-2006 and an oligotrophic rating in 2007.