Back to Top

 Skip navigation

Extent - EPA Water Framework Directive Data

Extent - EPA Water Framework Directive Data

More than 40% of Ireland's total lake area occurred in Galway and Mayo

CSO statistical publication, , 11am
A CSO Frontier Series Output

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. 

EPA Water Framework Directive Data

Rivers and canals

The extent of the river network can be seen in Map 3.1, occurring in almost every part of the country. This map also shows the location of selected canals (note that this is a subset of the canal network and includes just the canals monitored by Waterways Ireland for ecological status). The total length of rivers and canals was more than 74,000km (Table 3.1). Three counties each had more than 10% of the total length of rivers; Cork (7,584km), Donegal (7,867km), and Mayo (7,464km) (Table 3.1, Figure 3.1, Map 3.2). Dublin, Longford, and Louth had the shortest total length of rivers, at less than 900km or around 1% of the total length in each county. 

As part of the work done for the implementation of the Water Framework Directive (WFD), the Environmental Protection Agency (EPA) has mapped Ireland's waters, focusing on the length of rivers and not their area. For more information, see Background Notes.

Map 3.1 Distribution of rivers and canals, using EPA WFD data

Table 3.1 Length of rivers and canals by county (based on EPA WFD data)
kilometers %1
CountyRiversCanalsRivers and Canals RiversCanalsRivers and Canals
Carlow9710971 1.30.01.3
Cavan2,09702,097 2.80.02.8
Clare2,88702,887 3.90.03.9
Cork7,58407,584 10.20.010.2
Donegal7,86707,867 10.60.010.6
Dublin89039929 1.210.41.2
Galway5,70105,701 7.70.07.7
Kerry6,46306,463 8.70.08.7
Kildare1,1061231,229 1.532.71.7
Kilkenny1,51201,512 2.00.02.0
Laois1,528131,541 2.13.52.1
Leitrim2,115262,141 2.96.92.9
Limerick3,02703,027 4.10.04.1
Longford81835853 1.19.31.1
Louth8200820 1.10.01.1
Mayo7,46407,464 10.10.010.0
Meath2,202212,223 3.05.63.0
Monaghan1,41001,410 1.90.01.9
Offaly1,423711,494 1.918.92.0
Roscommon1,87201,872 2.50.02.5
Sligo2,42502,425 3.30.03.3
Tipperary4,12004,120 5.60.05.5
Waterford1,87901,879 2.50.02.5
Westmeath1,329471,376 1.812.51.8
Wexford2,37302,373 3.20.03.2
Wicklow2,20002,200 3.00.03.0
Ireland74,08337674,459 100.0100.0100.0
1 Due to rounding, percentages may not sum to 100
X-axis labelRivers
Donegal7867
Cork7584
Mayo7464
Kerry6463
Galway5701
Tipperary4120
Limerick3027
Clare2887
Sligo2425
Wexford2373
Meath2202
Wicklow2200
Leitrim2115
Cavan2097
Waterford1879
Roscommon1872
Laois1528
Kilkenny1512
Offaly1423
Monaghan1410
Westmeath1329
Kildare1106
Carlow971
Dublin890
Louth820
Longford818
Map 3.2 Percentage of total length of rivers by county

Lakes and reservoirs

The total area of lakes in Ireland was 125,111 hectares, while reservoirs covered 3,473 hectares (Table 3.2). The distribution of lakes and reservoirs can be seen in Map 3.3, with the majority of lakes occurring in the midlands and west/northwest of the country, while the reservoirs can be seen in the Wicklow and Cork areas. More than 22% of the area covered by lakes occurred in Galway (28,489ha), with almost 18% in Mayo (22,394ha), as shown in Table 3.2, Figure 3.2, and Map 3.4. Carlow, Dublin, Kildare, Kilkenny, Laois, and Louth each had less than 100 hectares of lake ecosystems. Just under two-thirds of the total area of reservoirs was in Wicklow (2,224ha), while about one third was in Cork (1,094ha).

Map 3.3 Distribution of lakes and reservoirs, using EPA WFD data

Table 3.2 Area of lakes and reservoirs by county (based on EPA WFD data)
hectares %1
CountyLakesReservoirsLakes and Reservoirs LakesReservoirsLakes and Reservoirs
Carlow10010 0.00.00.0
Cavan6,87606,876 5.50.05.3
Clare7,99027,992 6.40.16.2
Cork1,0091,0942,103 0.831.51.6
Donegal7,97727,979 6.40.16.2
Dublin6853122 0.11.50.1
Galway28,498<128,499 22.80.022.2
Kerry6,42316,424 5.10.05.0
Kildare7357130 0.11.60.1
Kilkenny36238 0.00.10.0
Laois53053 0.00.00.0
Leitrim8,36708,367 6.70.06.5
Limerick30623329 0.20.70.3
Longford4,67114,672 3.70.03.6
Louth938101 0.10.20.1
Mayo22,394122,396 17.90.017.4
Meath7820782 0.60.00.6
Monaghan2,09202,092 1.70.01.6
Offaly1460146 0.10.00.1
Roscommon9,161<19,162 7.30.07.1
Sligo4,28454,289 3.40.13.3
Tipperary5,239<15,239 4.20.04.1
Waterford1720172 0.10.00.1
Westmeath7,38307,383 5.90.05.7
Wexford7030703 0.60.00.5
Wicklow3042,2242,527 0.264.02.0
Ireland125,1113,473128,584 100.0100.0100.0
1 Due to rounding, percentages may not sum to 100
X-axis labelLakesReservoirs
Galway284980.5
Mayo223941
Roscommon91610.5
Leitrim83670
Clare79902
Donegal79772
Westmeath73830
Cavan68760
Kerry64231
Tipperary52390.5
Longford46711
Sligo42845
Wicklow3042224
Cork10091094
Monaghan20920
Meath7820
Wexford7030
Limerick30623
Waterford1720
Offaly1460
Kildare7357
Dublin6853
Louth938
Laois530
Kilkenny362
Carlow100
Map 3.4 Percentage of total area of lakes by county