Jero Lake
Jero Lake in Lieksa, Finland has official water-quality measurements, not a LakeQuality A–F grade. Water clarity: 4.2 m visibility. Phosphorus: 3.7 µg/L. Chlorophyll-a (algae): 2.9 µg/L. Maximum depth: 88.6 ft.
- Clarity
- 4.2 m
- Max depth
- 27 m
Why Jero Lake has no A–F grade
Jero Lake in Finland 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 water clarity, phosphorus and algae (chlorophyll-a).
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 Finnish Environment Institute (Syke) and the ELY Centres.
Jero Lake is a lake in Lieksa County, Finland with a maximum depth of 89 feet.
Source: EPA Water Quality Portal sampling records, your state environmental agency, last sampled 2025-09-01. Grade methodology: LakeGrade methodology.
Watch Jero Lake 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 Jero Lake
These readings exist but do not meet the evidence bar for an A–F grade — see why.
Good clarity, visible to about 13.9 ft. Phosphorus level: 3.7 µg/L. Chlorophyll-a: 2.9 µg/L. Trophic State Index: 34.
| Metric | Value | Grade |
|---|---|---|
| Water Clarity (Secchi Depth) | 4.22 m | Not graded |
| Phosphorus | 3.7 µg/L | Not graded |
| Chlorophyll-a (Algae) | 2.9 µg/L | Not graded |
| Trophic State Index (TSI) | 34 | Oligotrophic |
Low nutrients, clear water, excellent for swimming
Lake Details
| Characteristic | Value |
|---|---|
| Maximum Depth | 27 m |
Where to stay near Jero Lake
Compare lakeside cabins, hotels, and vacation rentals near Jero Lake in Lieksa, Finland — 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 Jero Lake
Availability and prices from Stay22 partners (Booking.com, Vrbo, Expedia). We may earn a commission from bookings, at no extra cost to you.
Fishing Jero Lake
Frequently asked questions about Jero Lake
What is the water quality of Jero Lake?
- Jero Lake in Lieksa, Finland has official water-quality measurements, not a LakeQuality A–F grade. Water clarity: 4.2 m visibility. Phosphorus: 3.7 µg/L. Chlorophyll-a (algae): 2.9 µg/L. Maximum depth: 88.6 ft.
Is Jero Lake safe to swim in?
- Jero Lake 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.
How deep is Jero Lake?
- Jero Lake has a maximum depth of 88.6 feet.
Explore Jero Lake across LakeGrade
More lakes in Finland
Where this data comes from
31 measurements from 1 monitoring station, 2016–2025. Retrieved from Syke VESLA (not the EPA Water Quality Portal) on 2026-08-16.
Collected and reported by
- Finnish Environment Institute (Syke) and ELY Centres
syke-vesla31 samples · 2016–2025
Analytical methods
- SYKE VESLA
Monitoring station identifiers (1)
23063
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: 2025-09-01
Monitoring stations: 1