Lough Allen
Leitrim, IrelandView mapDirections
EPA Ireland publishes the water-quality measurements for Lough Allen. Here is what has been measured.
- Limited data
Lough Allen in Leitrim, Ireland has official water-quality measurements, shown as reported. Phosphorus: 16 µg/L. Chlorophyll-a (algae): 3.4 µg/L.
How Lough Allen is classified
Lough Allen in Ireland is published with the authority's own measurements and class. The measurements here are published by the agency that samples the lake, as reported. Sampling here has recorded phosphorus and algae (chlorophyll-a), but not water clarity.
LakeQuality publishes no grade of its own beside it. Everything below thathas been measured is reported on this page.
Monitoring: the Environmental Protection Agency of Ireland, via UNEP GEMS/Water, with WFD lake names from EPA Ireland.
Lough Allen is a lake in Leitrim County, Ireland.
Source: the Environmental Protection Agency of Ireland, via UNEP GEMS/Water, with WFD lake names from EPA Ireland — not the EPA Water Quality Portal, last sampled 2022-10-12. Methodology: how these readings are compared.
Swimming conditions
No readingLimited data
Nutrient and algae readings are not a swimming clearance. Check local advisories before you swim.
Whether Lough Allen is safe to swim in today is a call for the Environmental Protection Agency of Ireland, via UNEP GEMS/Water, with WFD lake names from EPA Ireland and the county health department, who post current advisories. LakeQuality does not issue swimming clearances.
Water quality measurements for Lough Allen
These are the measurements EPA Ireland publishes for Lough Allen. More on the source.
No clarity data. Phosphorus 16 µg/L. Chlorophyll-a 3.4 µg/L. TSI 43.
| Measure | Reading | Where it sits |
|---|---|---|
| Water clarity (Secchi depth) | No reading How deep a black-and-white disk stays visible from the surface. Higher is clearer. | |
| Total phosphorus | 16µg/L | Measured, not scored The nutrient that most limits algae growth in freshwater. More phosphorus, more algae potential. |
| Chlorophyll-a (algae) | 3.4µg/L | Measured, not scored The green pigment in algae — a direct measure of how much algae is in the water. |
| Trophic state (TSI)Carlson's 0–100 index of how much algae a lake can support, from clarity, phosphorus and chlorophyll-a. | 43 | Mesotrophic OligotrophicMesotrophicEutrophicHypereutrophic |
Moderate nutrients, good water quality
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Frequently asked questions about Lough Allen
Where is Lough Allen?
- Lough Allen is a lake in Leitrim, Ireland. This page reports official water-quality measurements, shown as reported.
What is the water quality of Lough Allen?
- Lough Allen in Leitrim, Ireland has official water-quality measurements, shown as reported. Phosphorus: 16 µg/L. Chlorophyll-a (algae): 3.4 µg/L.
Is Lough Allen safe to swim in?
- Lough Allen has official nutrient and clarity measurements, not a bacteria swim class and not a safety clearance. Algal blooms, currents, and depth are not covered. Always check local notices before swimming.
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Where this data comes from
77 measurements from 7 monitoring stations, 2018–2022. Retrieved from UNEP GEMS/Water GFQA (not the EPA Water Quality Portal) on 2026-08-16.
Collected and reported by
- European Environment Agency
europeanenvironmentagenc77 samples · —
Analytical methods
- GEMStat OPEN / CC BY 4.0
- EPA Ireland WFD lake waterbodies CC BY 4.0
Monitoring station identifiers (7)
IRL00314IRL00315IRL00316IRL00317IRL00318IRL00319IRL00320
Authority classifications are shown as the authority published them. See where the data comes from and data sources.