Lough Arrow
Sligo, IrelandView mapDirections
EPA Ireland publishes the water-quality measurements for Lough Arrow. Here is what has been measured.
- Limited data
Lough Arrow in Sligo, Ireland has official water-quality measurements, shown as reported. Phosphorus: 13 µg/L. Chlorophyll-a (algae): 2.2 µg/L.
How Lough Arrow is classified
Lough Arrow 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 Arrow is a lake in Sligo 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 2023-12-05. 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 Arrow 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 Arrow
These are the measurements EPA Ireland publishes for Lough Arrow. More on the source.
No clarity data. Phosphorus 13 µg/L. Chlorophyll-a 2.2 µg/L. TSI 40.
| 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 | 13µg/L | Measured, not scored The nutrient that most limits algae growth in freshwater. More phosphorus, more algae potential. |
| Chlorophyll-a (algae) | 2.2µg/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. | 40 | Oligotrophic OligotrophicMesotrophicEutrophicHypereutrophic |
Low nutrients, clear water. No reading is a swimming clearance.
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Frequently asked questions about Lough Arrow
Where is Lough Arrow?
- Lough Arrow is a lake in Sligo, Ireland. This page reports official water-quality measurements, shown as reported.
What is the water quality of Lough Arrow?
- Lough Arrow in Sligo, Ireland has official water-quality measurements, shown as reported. Phosphorus: 13 µg/L. Chlorophyll-a (algae): 2.2 µg/L.
Is Lough Arrow safe to swim in?
- Lough Arrow 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
371 measurements from 5 monitoring stations, 2016–2023. Retrieved from UNEP GEMS/Water GFQA (not the EPA Water Quality Portal) on 2026-08-16.
Collected and reported by
- European Environment Agency
europeanenvironmentagenc371 samples · —
Analytical methods
- GEMStat OPEN / CC BY 4.0
- EPA Ireland WFD lake waterbodies CC BY 4.0
Monitoring station identifiers (5)
IRL00144IRL00145IRL00146IRL00470IRL00471
Authority classifications are shown as the authority published them. See where the data comes from and data sources.