This publication is categorised as a CSO Frontier Series Output. Particular care must be taken when interpreting the statistics in this release as it may use new methods which are under development and/or data sources which may be incomplete, for example new administrative data sources.
This publication uses a new approach to examine the condition of Ireland's river and lake ecosystems, and how this has changed over time. Based on the System of Environmental-Economic Accounting - Ecosystem Accounting (SEEA-EA), Ecosystem Condition Accounts were compiled for Ireland's rivers and lakes. We used data from the Environmental Protection Agency (EPA) to compare the assessment periods 2010-2015 and 2016-2021, corresponding to the first and second cycles of our national River Basin Management Plans (RBMPs).
There was a decrease in the overall condition of river ecosystems between the 2010-2015 and 2016-2021 assessment periods, with 9% fewer river water bodies in Good or High ecological status.
Overall, around 51% of monitored river water bodies were in Good or High ecological status in 2016-2021, while 49% were in Moderate, Poor, or Bad ecological status.
Louth (20%), Dublin (21%), and Kildare (21%) were the counties with the lowest proportion of river water bodies in Good or High ecological status in the 2016-2021 assessment period, while the counties with the highest proportion of the same status were Cork (73%), Leitrim (72%), and Wicklow (71%).
The catchments with the highest percentage of river water bodies in Good or High ecological status in the 2016-2021 period at 79% were Erriff-Clew Bay (in the Galway/Mayo area) and Dunmanus-Bantry-Kenmare (West Cork and Co. Kerry). The catchments with the lowest percentages were the Nanny-Delvin in the Dublin/Meath area (9%) and the Upper Shannon (26G) in the Athlone region (10%).
There was a small improvement in the overall condition of lake ecosystems between the EPA's 2010-2015 and 2016-2021 assessment periods, with a 4% increase in the number of lake water bodies in Good or High ecological status.
Around 48% of the lake water bodies monitored in 2016-2021 were in Good or High ecological status, with 52% in Moderate, Poor or Bad status.
The catchments with the highest percentage of lake water bodies assigned a High ecological status in 2016-2021 were Galway Bay North and Dunmanus-Bantry-Kenmare (both at 50%).
Six catchments had at least one lake water body in Bad ecological status in 2016-2021 (Erne, Erriff-Clew Bay, Sligo Bay & Drowse, Mal Bay (Co. Clare), Lower Shannon (25C) (in the midlands), and Lough Swilly (Co. Donegal)).
The Environmental Protection Agency (EPA) is responsible for monitoring Ireland's water bodies as part of the Water Framework Directive (WFD). More information on the WFD in Ireland is available from the Department of Housing, Local Government and Heritage and from the EPA.
River and lake water bodies are classified into five quality classes (or statuses) under the WFD:
An ecological status of High or Good is considered satisfactory; a status of Moderate, Poor or Bad is unsatisfactory. See Background Notes for more information.
Data for this publication were downloaded from the EPA's Geoportal. Data for five assessment periods were available when these preliminary ecosystem condition accounts were being compiled.
Data on ecological status of water bodies were used to compile preliminary ecosystem condition accounts for rivers and lakes. Ecosystem condition accounts record the condition of ecosystem assets (in this case water bodies) in terms of selected characteristics (in this case ecological status) at specific points in time. Over time, the accounts record changes in condition, and can provide valuable information on the health and functioning of ecosystems, and their ability to provide ecosystem services.
Ireland has 46 catchments used as the main management units in the national River Basin Management Plans (RBMPs). A catchment is an area of land draining towards a river, lake, or other body of water. Each catchment is identified by a name and a catchment code. There are seven Upper Shannon catchments, and four Lower Shannon catchments; where these are referred to in the text, the catchment code is included to distinguish between them. Catchments do not neatly fit into administrative boundaries such as counties, but where appropriate we have included the county or counties in which a catchment is located to provide context to the results.
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Statistician's Comment
The Central Statistics Office (CSO) has today (23 August 2023) published Ecosystem Condition Accounts - Rivers and Lakes 2021.
Commenting on the release, Nova Sharkey, Statistician in the Ecosystem Accounts Division, said:
"This release, published as part of the CSO’s Frontier Series, looks at the condition of our river and lake ecosystems. It uses Water Framework Directive reporting data produced by the Environmental Protection Agency (EPA) to compile ecosystem condition accounts for rivers and lakes.
Overall Results
Around 51% of monitored river water bodies were in Good or High ecological status in 2016-2021, while 49% had a Moderate, Poor, or Bad ecological status. When we look at lake water bodies, around 48% were in Good or High ecological status in the same assessment period, with 52% assigned a Moderate, Poor, or Bad ecological status. This means that around half of our river and lake ecosystems failed to reach the objectives set out in the Water Framework Directive. Only river and lake ecosystems in good condition can provide us with a full suite of ecosystem services, including clean water for drinking, habitats for biodiversity, flood protection, and cultural and recreational services.
It is worth noting that the total number of river water bodies monitored by the EPA has been increasing since the 2007-2009 assessment period, from 2,161 to 2,398. The percentage of monitored river water bodies reaching Good or High status was highest in the 2010-2012 period at 60% (1,369 water bodies). However, there has been a decrease in ecological status in every assessment period since then, with around 51% (1,234 water bodies) achieving Good or High ecological status in 2016-2021. The number of monitored river water bodies assigned a Bad ecological status has decreased from 19 in the 2007-2009 assessment period to five in the 2016-2021 period (See Figure 2.3 and Table 2.3).
County Results
The counties with the lowest percentages of monitored river water bodies in Good or High ecological status in the 2016-2021 assessment period were Louth (20%), Dublin (21%), and Kildare (21%). Cork (73%), Leitrim (72%), and Wicklow (71%) were the counties with the highest percentages of river water bodies in Good or High ecological status (See Figure 2.4 and Table 2.4).
Changes Over Time – Rivers and Lakes
Ecosystem condition accounts were compiled to compare water bodies monitored in both the first (2010-2015) and second (2016-2021) cycles of Ireland's River Basin Management Plans (RBMPs). These accounts showed that there was a 9% decrease (113 water bodies) in the number of river water bodies reaching Good or High ecological status.
Looking at lake water bodies monitored over both cycles of the RBMPs, there was an increase of around 4% in the number of water bodies reaching Good or High ecological status. While this 4% rise accounts for an increase of four water bodies, it was a large percentage increase in terms of area (around 43%, or almost 18,000 hectares) (See Table 2.1).
Changes Over Time - Catchments
Ecosystem condition accounts based on ecological status were also compiled at catchment level, comparing the same assessment periods (2010-2015 and 2016-2021).
For river water bodies, the Upper Shannon (26G), in the Athlone region, was the catchment with the largest negative percentage change in number of water bodies in Good or High ecological status, going from 40% (four water bodies) to 10% (one water body), a 75% decrease.
The Owenavorragh catchment, which covers the area drained by the River Owenavorragh in Co. Wexford, saw the largest percentage increase, from 6% (one water body) to 35% (six water bodies), a five-fold increase (See Table 3.1a and Table 3.1c).
When we examined the change in ecological status of lake water bodies, five catchments had no water bodies achieving Good or High status in either assessment period. These were the Colligan-Mahon catchment in Co. Waterford, the Tralee Bay-Feale catchment, and three Shannon catchments in the midlands (Lower Shannon (25C), Upper Shannon (26A), and Upper Shannon (26B)).
The Blacksod-Broadhaven (Co. Mayo) and Mal Bay (Co. Clare) catchments both saw a decrease of 50% (from two water bodies to one water body). The largest percentage increase was in the Galway Bay South East catchment, which went from around 33% (one water body) to 100% (three water bodies) at Good or High ecological status, up 200% (See Table 3.2a, Table 3.2c, and Figure 3.2)."