Lough Farnharn
Lough Farnharn in Cavan, Ireland has official water-quality measurements, not a LakeQuality A–F grade. Phosphorus: 170 µg/L. Chlorophyll-a (algae): 2.5 µg/L.
Why Lough Farnharn has no A–F grade
Lough Farnharn in Ireland is published with the authority's own measurements, not a LakeQuality letter. official authority class; not a LakeQuality A–F letter Sampling here has recorded phosphorus and algae (chlorophyll-a), but not water clarity.
A letter on the LakeQuality scale would be an invention, not an official class. Everything below that has been measured is still reported on this page.
Monitoring: the Environmental Protection Agency of Ireland, via UNEP GEMS/Water, with WFD lake names from EPA Ireland.
Lough Farnharn is a lake in Cavan County, Ireland.
Source: EPA Water Quality Portal sampling records, your state environmental agency, last sampled 2022-10-25. Grade methodology: LakeGrade methodology.
Watch Lough Farnharn water quality
Subscribe for LakeQuality updates by email. No spam, unsubscribe anytime.
Swimming Safety
Not ratedLimited data
Not rated for swimming — there is not enough monitoring data to judge this lake
Water quality measurements for Lough Farnharn
These readings exist but do not meet the evidence bar for an A–F grade — see why.
No clarity data. Phosphorus level: 170 µg/L. Chlorophyll-a: 2.5 µg/L. Trophic State Index: 59.
| Metric | Value | Grade |
|---|---|---|
| Water Clarity (Secchi Depth) | No recent samples | |
| Phosphorus | 170 µg/L | Not graded |
| Chlorophyll-a (Algae) | 2.5 µg/L | Not graded |
| Trophic State Index (TSI) | 59 | Eutrophic |
High nutrients, frequent algae, reduced clarity
Where to stay near Lough Farnharn
Compare lakeside cabins, hotels, and vacation rentals near Lough Farnharn in Cavan, 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.
Top-rated places to stay near Lough Farnharn
Availability and prices from Stay22 partners (Booking.com, Vrbo, Expedia). We may earn a commission from bookings, at no extra cost to you.
Fishing Lough Farnharn
Frequently asked questions about Lough Farnharn
What is the water quality of Lough Farnharn?
- Lough Farnharn in Cavan, Ireland has official water-quality measurements, not a LakeQuality A–F grade. Phosphorus: 170 µg/L. Chlorophyll-a (algae): 2.5 µg/L.
Is Lough Farnharn safe to swim in?
- Lough Farnharn 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.
Explore Lough Farnharn across LakeGrade
More lakes in Ireland
Where this data comes from
11 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 Agency
europeanenvironmentagenc11 samples · —
Analytical methods
- GEMStat OPEN / CC BY 4.0
- EPA Ireland WFD lake waterbodies CC BY 4.0
Monitoring station identifiers (1)
IRL00239
Authority classifications are stored separately from LakeQuality A–F letters and are never blended. See methodology and data sources.
Data Sources
Water quality data from the EPA Water Quality Portal
Grade thresholds from the EPA National Lakes Assessment (EPA 841-R-24-006, Table 6-3), applied by ecoregion
Most recent sample: 2022-10-25
Monitoring stations: 1