Jonku Lake
Jonku Lake in Pudasjärvi, Finland has official water-quality measurements, not a LakeQuality A–F grade. Water clarity: 1.6 m visibility. Phosphorus: 17 µg/L. Chlorophyll-a (algae): 8.6 µg/L. Maximum depth: 10.8 ft.
- Clarity
- 1.6 m
- Max depth
- 3.3 m
Why Jonku Lake has no A–F grade
Jonku 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.
Jonku Lake is a lake in Pudasjärvi County, Finland with a maximum depth of 11 feet.
Source: EPA Water Quality Portal sampling records, your state environmental agency, last sampled 2025-09-17. Grade methodology: LakeGrade methodology.
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Swimming Safety
Not ratedLimited data
Not rated for swimming — there is not enough monitoring data to judge this lake
Water quality measurements for Jonku Lake
These readings exist but do not meet the evidence bar for an A–F grade — see why.
Murky, only visible to about 5.2 ft. Phosphorus level: 17 µg/L. Chlorophyll-a: 8.6 µg/L. Trophic State Index: 50.
| Metric | Value | Grade |
|---|---|---|
| Water Clarity (Secchi Depth) | 1.6 m | Not graded |
| Phosphorus | 17 µg/L | Not graded |
| Chlorophyll-a (Algae) | 8.6 µg/L | Not graded |
| Trophic State Index (TSI) | 50 | Mesotrophic |
Moderate nutrients, good water quality
Lake Details
| Characteristic | Value |
|---|---|
| Maximum Depth | 3.3 m |
Where to stay near Jonku Lake
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Fishing Jonku Lake
Frequently asked questions about Jonku Lake
What is the water quality of Jonku Lake?
- Jonku Lake in Pudasjärvi, Finland has official water-quality measurements, not a LakeQuality A–F grade. Water clarity: 1.6 m visibility. Phosphorus: 17 µg/L. Chlorophyll-a (algae): 8.6 µg/L. Maximum depth: 10.8 ft.
Is Jonku Lake safe to swim in?
- Jonku 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 Jonku Lake?
- Jonku Lake has a maximum depth of 10.8 feet.
Explore Jonku Lake across LakeGrade
More lakes in Finland
Where this data comes from
36 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-vesla36 samples · 2016–2025
Analytical methods
- SYKE VESLA
Monitoring station identifiers (1)
28736
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: 2025-09-17
Monitoring stations: 1