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LakeQuality

Lough Finn

Donegal, IrelandView mapDirections

EPA Ireland publishes the water-quality measurements for Lough Finn. Here is what has been measured.

Phosphorus
29 µg/L
More phosphorus than most
Measured by EPA Ireland
Chlorophyll-a
4.2 µg/L
Typical for Ireland
Measured by EPA Ireland
  • Limited data

Lough Finn in Donegal, Ireland has official water-quality measurements, shown as reported. Phosphorus: 29 µg/L. Chlorophyll-a (algae): 4.2 µg/L.

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How Lough Finn is classified

Lough Finn 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 Finn is a lake in Donegal 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 2022-10-19. Methodology: how these readings are compared.

Swimming conditions

No reading

Limited data

Nutrient and algae readings are not a swimming clearance. Check local advisories before you swim.

Whether Lough Finn 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.

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Water quality measurements for Lough Finn

These are the measurements EPA Ireland publishes for Lough Finn. More on the source.

No clarity data. Phosphorus 29 µg/L. Chlorophyll-a 4.2 µg/L. TSI 49.

Water quality readings
MeasureReadingWhere it sits
Water clarity (Secchi depth)No reading

How deep a black-and-white disk stays visible from the surface. Higher is clearer.

Total phosphorus29µg/LMeasured, not scored

The nutrient that most limits algae growth in freshwater. More phosphorus, more algae potential.

Chlorophyll-a (algae)4.2µg/LMeasured, 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.49Mesotrophic
OligotrophicMesotrophicEutrophicHypereutrophic

Moderate nutrients, good water quality

Ask about Lough Finn

Answers come straight from the public measurements and survey records on this page.

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Stays near Lough Finn

Compare lakeside cabins, hotels, and vacation rentals near Lough Finn in Donegal, Ireland — live availability and prices for your trip. Switch the map to Satellite to see the lake and how close each stay is to the water.

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Fishing Lough Finn

Frequently asked questions about Lough Finn

Where is Lough Finn?

Lough Finn is a lake in Donegal, Ireland. This page reports official water-quality measurements, shown as reported.

What is the water quality of Lough Finn?

Lough Finn in Donegal, Ireland has official water-quality measurements, shown as reported. Phosphorus: 29 µg/L. Chlorophyll-a (algae): 4.2 µg/L.

Measurements on this page ↑

Is Lough Finn safe to swim in?

Lough Finn 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.

Swimming on this page ↑

Where this data comes from

7 measurements from 1 monitoring station, 2018–2022. Retrieved from UNEP GEMS/Water GFQA (not the EPA Water Quality Portal) on 2026-08-16.

Collected and reported by

  • European Environment Agencyeuropeanenvironmentagenc7 samples · —

Analytical methods

  • GEMStat OPEN / CC BY 4.0
  • EPA Ireland WFD lake waterbodies CC BY 4.0
Monitoring station identifiers (1)
  • IRL00224

Authority classifications are shown as the authority published them. See where the data comes from and data sources.