Avonbeg–Avonmore Priority Area for Action: Desk Study Summary

Avonbeg–Avonmore Priority Area for Action: Desk Study Summary Below, we summarise the desk-top assessment findings for the Avonbeg–Avonmore Priority Area for Action (PAA). Desk-top reports are, as the name suggests, written at our desks. To write these reports, we use information about each of the Avonmore and Avonbeg rivers that we assess. This is a water based assessment at a particular point in time (up to March 2020) to identify the issues and pressures. We get our information from: • The Environmental Protection Agency • Local authorities • Inland Fisheries Ireland • Irish Water • Other public agencies In our desk-top reports, we tell you about a particular river, lake, or coastal waters: • quality–how the water quality has changed over the past 3–6 years. • importance–for example, we at if it is water used for drinking water, and if there are any rare plants or and animals in it, we need to protect. • impacts from human activity–here we focus on impacts that damage water quality such as wastewater treatment, agriculture, forestry, physical changes to the water. We complete desk studies first before starting our field-based assessments or local catchment assessments (LCAs), so an LCA report contains the most up-to-date information, where available. 1 1. Background and Location LAWPRO catchment scientists work in specific catchment areas called Priority Areas for Action (PAAs). A catchment is an area of land around a river, lake, or other body of water. Rainwater that falls in the catchment flows to the river, lake, or coastline. Rainwater that falls within a catchment eventually flows into rivers, lakes, or directly into estuaries or coastal waters bringing with it any contaminants that may be in the landscape. The total land area included in the PAA is based upon the combined catchment areas of each of the four rivers. A river’s catchment is derived from the topography of the landscape, where all water that falls onto that catchment area flows into one river. When the river is large, we spilt it into smaller, more manageable sections. Each of these river sections has a smaller catchment area with a unique code, which we call waterbodies. At the bottom of these waterbodies, there are monitoring points, which are used to measure the quality of the incoming water. The Avonbeg-Avonmore PAA is in County Wicklow. It is divided into four sections or waterbodies, which are distinguished by a unique number (shown in Map 1 and Map 2): • Avonbeg_010: This waterbody is the headwater to Avonbeg river. It rises in Wicklow Mountains (at Camenabologue Mountain) in the area southwest from Glendalough. It then flows southeast to Glenmalure. • Avonbeg_020: This waterbody flows through Glenmalure valley to Glenmalure town. • Avonmore_010: This waterbody (also known as Cloghoge River), rises in the Wicklow Mountains northwest of Roundwood. It flows south through Lough Tay. • Avonmore_020: This waterbody relates to Inchavore River flowing into Lough Dan and to the Oldbridge town. 2 Photo 1: Lough Dan in Avonmore_020 waterbody. Photo 2: View of the Avonmore_010 catchment downstream of the Lough Tay. 3 2. Catchment description This PAA is mainly in the Wicklow Mountains. The main land cover is peatbogs and forestry (mainly Coillte conifer forests). The geology and soil type within a catchment determines how water moves. Soils are often wet with peaty soils, mainly in the uplands. There are very thin subsoils with granite bedrock underneath. Avonmore_010 and Avonmore_020 are Freshwater Pearl Mussel (Margaritifera) sensitive area (these are not designated sites that include extant populations). Avonmore_010 and Avonmore_020 are also Blue Dot catchments meaning that historically they were in near pristine conditions (achieving high ecological status). 3. Water Quality history in the Avonbeg-Avonmore PAA Rivers are classified into five quality classes (status), with high being unpolluted and bad being the most polluted. High Good Moderate Poor Bad The Environmental Protection Agency assign status at (approximately) 3-yearly intervals based on the standards set out in European legislation, the Water Framework Directive. Status is based on many elements that altogether show the overall health of the river, for example, the ecology recorded in river habitats, the physico-chemical condition of the river (oxygen levels, nutrient concentrations, indicators of organic and chemical pollution etc) and also the physical condition of the river bed and bank. 4 Map 1: The Avonbeg-Avonmore PAA (Avonmore_010 and Avonmore_020), ecological status, location of monitoring points and waterbody catchment areas. 5 Map 2: The Avonbeg-Avonmore PAA (Avonbeg_010 and Avonbeg_020), ecological status, location of monitoring points and waterbody catchment areas. We need to make sure that the Avonbeg_010 and Avonbeg_020 achieve Good status, and Avonmore_010 and Avonmore_020 achieve High status. We have reviewed water quality data available for each of the waterbodies (Table 1) and we have found that: Table 1: Water quality status and findings Waterbody Status (2013 – 2018) Our findings Avonbeg_010 Good This is the required status for this waterbody. That means we need to protect it to maintain these conditions. There is, however, a risk of status failure due to low pH (acidification) in this waterbody. Avonbeg_020 Good This is the required status for this waterbody. We also need to protect this 6 waterbody to maintain these conditions. This site is also at risk of failing acidification conditions. Avonmore_010 Good We need to restore this waterbody to High conditions. We think that acidification and too much sediment may cause the decline in water quality. Avonmore_020 Good We need to restore this waterbody to High conditions. We think that acidification, too much sediment and also nutrients may cause the decline in water quality. 4. Sources of Pollution Pollutants find their way to rivers by several paths: • They can be through pipes directly connected to the river from large sources such as wastewater treatment plants, or minor sources such as faulty septic tanks, farmyards, roadside drains. • They can flow across the ground to the river when nutrients applied to the land as fertiliser wash off by rainfall before the crop and soil has absorbed them. This can also relate to soil being washed off the land. This is usually a problem where soils are wetter and poorly draining, particularly during wet weather. • Groundwater losses occur when pollutants move down through the soil and rock into groundwater and eventually into rivers, lakes, and coastal waters. This usually occurs when too much fertiliser is applied to land, or when the soil is not ready to absorb the nutrient (e.g., temperatures too cold, incorrect soil pH etc) and is common in free- draining/ light soils. EPA identified forestry, atmospheric deposition and agriculture as the pressures affecting water quality in this PAA. • Forestry was identified as a pressure at all four waterbodies in this PAA. Forestry operations can cause physical impacts to the river habitats mainly due to soil losses but also nutrient inputs to the river during forestry operations (clearfelling, planting). Land drainage associated with forestry activities can also increase inputs of 7 dissolved organic carbon that is leached from drained peat. That can cause increased acidity in the river. • Atmospheric deposition was identified by the EPA as a significant pressure in Avonmore_010. This is because historically burning of the fossil fuels caused air pollution (mainly sulphur and nitrogen compounds). These chemicals could be deposited in the catchment (or intercepted by forestry canopies) and when washed off to the river could cause acidification issues. In our desk study we have reviewed long-term monitoring research data located close to Avonmore_010, which showed reductions in deposition of sulphur and nitrogen compounds. We have concluded that atmospheric deposition is not the primary cause of acidification risk in this waterbody. • Agriculture was identified as a pressure in Avonmore_010 due to physical changes. Exact issues arising from agriculture are not known. There are two commonage areas in this waterbody. Considering slight to moderate siltation being identified as an issue, overgrazing, peat erosion, water drinking access points or peat extraction may be potential sediment sources in this waterbody. All four waterbodies are at risk from acidification (Table 2), this is where the pH values are lower than normal. Acidification can result from the natural physical conditions (geology, soils, topography) of the catchment. Land drainage activities associated with forestry and peat cutting can exacerbate acidification. We will investigate the causes of acidification and their links to catchment characteristics and pressures in the Wicklow rivers through the pH Review project with the EPA. 8 Table 2 Ecological status, pressures, and significance in the Avonbeg-Avonmore PAA (high status objective water bodies highlighted in columns 1 and 2 in blue). EPA Desk Study Desk study Ecological Status EPA Characterisation Review Review Characterisation Waterbody Significant Pressure Potential Potential Waterbody Code Waterbody name Risk Significant Type Category (Sub- Additional Significant 2007 - 2010 - 2010 - 2013 - Issue category) Pressures Issue 2009 2012 2015 2018 (2013-2015) (2013-2015) IE_EA_10A040100 AVONBEG_010 River At Risk Good Good Moderate Good Forestry (forestry) Acidification Acidification Acidification, IE_EA_10A040400 AVONBEG_020

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