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Jonku Lake

Pudasjärvi, FinlandView mapDirections

Syke publishes the water-quality measurements for Jonku Lake. Here is what has been measured.

Clarity
1.6 m
Typical for Finland
Secchi · sampled 2025
Phosphorus
17 µg/L
Typical for Finland
Measured by Syke
Chlorophyll-a
8.6 µg/L
Typical for Finland
Measured by Syke
Max depth
3.3 m
Bathymetric survey
  • 11 ft max depth
  • Limited data

Jonku Lake in Pudasjärvi, Finland has official water-quality measurements, shown as reported. Water clarity: 1.6 m visibility. Phosphorus: 17 µg/L. Chlorophyll-a (algae): 8.6 µg/L. Maximum depth: 10.8 ft.

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How Jonku Lake is classified

Jonku Lake in Finland 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 water clarity, phosphorus and algae (chlorophyll-a).

LakeQuality publishes no grade of its own beside it. Everything below thathas been measured is 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: the Finnish Environment Institute (Syke) and the ELY Centres — not the EPA Water Quality Portal, last sampled 2025-09-17. 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 Jonku Lake is safe to swim in today is a call for the Finnish Environment Institute (Syke) and the ELY Centres and the county health department, who post current advisories. LakeQuality does not issue swimming clearances.

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Water quality measurements for Jonku Lake

These are the measurements Syke publishes for Jonku Lake. More on the source.

Murky, only visible to about 5.2 ft. Phosphorus 17 µg/L. Chlorophyll-a 8.6 µg/L. TSI 50.

Water quality readings
MeasureReadingWhere it sits
Water clarity (Secchi depth)1.6mMeasured, not scored

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

Total phosphorus17µg/LMeasured, not scored

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

Chlorophyll-a (algae)8.6µg/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.50Mesotrophic
OligotrophicMesotrophicEutrophicHypereutrophic

Moderate nutrients, good water quality

Ask about Jonku Lake

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

Lake Details

Max depth

3.3 m

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Fishing Jonku Lake

Frequently asked questions about Jonku Lake

Where is Jonku Lake?

Jonku Lake is a lake in Pudasjärvi, Finland. This page reports official water-quality measurements, shown as reported.

What is the water quality of Jonku Lake?

Jonku Lake in Pudasjärvi, Finland has official water-quality measurements, shown as reported. Water clarity: 1.6 m visibility. Phosphorus: 17 µg/L. Chlorophyll-a (algae): 8.6 µg/L. Maximum depth: 10.8 ft.

Measurements on this page ↑

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.

Swimming on this page ↑

How deep is Jonku Lake?

Jonku Lake has a maximum depth of 10.8 feet.

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 Centressyke-vesla36 samples · 2016–2025

Analytical methods

  • SYKE VESLA
Monitoring station identifiers (1)
  • 28736

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