Where is Iso Hietajärvi?

Iso Hietajärvi is a lake in Posio, Finland. This page reports official water-quality measurements, shown as reported.

Is Iso Hietajärvi safe to swim in?

Iso Hietajärvi 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 Iso Hietajärvi?

Iso Hietajärvi has a maximum depth of 40.7 feet.

Iso Hietajärvi

Posio, FinlandView map Directions

Syke publishes the water-quality measurements for Iso Hietajärvi. Here is what has been measured.

Clarity

3.1 m

Clearer than most

Secchi · sampled 2022

Phosphorus

6.1 µg/L

Less phosphorus than most

Measured by Syke

Chlorophyll-a

10.5 µg/L

Typical for Finland

Measured by Syke

Max depth

12.4 m

Bathymetric survey

41 ft max depth
Limited data

See the measurements Directions Where to stay

Iso Hietajärvi in Posio, Finland has official water-quality measurements, shown as reported. Water clarity: 3.1 m visibility. Phosphorus: 6.1 µg/L. Chlorophyll-a (algae): 10.5 µg/L. Maximum depth: 40.7 ft.

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How Iso Hietajärvi is classified

Iso Hietajärvi 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.

Iso Hietajärvi is a lake in Posio County, Finland with a maximum depth of 41 feet.

Source: the Finnish Environment Institute (Syke) and the ELY Centres — not the EPA Water Quality Portal, last sampled 2022-09-12. Methodology: how these readings are compared.

What Iso Hietajärvi is good for

From access and monitoring records, not editorial picks.

Clear water10 ft of visibility
Deep water40.7 ft surveyed max depth

Swimming conditions

No reading

Limited data

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

Whether Iso Hietajärvi 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 Iso Hietajärvi

These are the measurements Syke publishes for Iso Hietajärvi. More on the source.

Good clarity, visible to about 10 ft. Phosphorus 6.1 µg/L. Chlorophyll-a 10.5 µg/L. TSI 43.

Water quality readings
Measure	Reading	Where it sits
Water clarity (Secchi depth)	3.05m	Measured, not scored How deep a black-and-white disk stays visible from the surface. Higher is clearer.
Total phosphorus	6.1µg/L	Measured, not scored The nutrient that most limits algae growth in freshwater. More phosphorus, more algae potential.
Chlorophyll-a (algae)	10.5µg/L	Measured, 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.	43	Mesotrophic OligotrophicMesotrophicEutrophicHypereutrophic

Moderate nutrients, good water quality

Ask about Iso Hietajärvi

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

Lake Details

Max depth

12.4 m

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Fishing Iso Hietajärvi

→ Iso Hietajärvi fishing regulations (limits, seasons, special rules)

Frequently asked questions about Iso Hietajärvi

Where is Iso Hietajärvi?: Iso Hietajärvi is a lake in Posio, Finland. This page reports official water-quality measurements, shown as reported.
What is the water quality of Iso Hietajärvi?: Iso Hietajärvi in Posio, Finland has official water-quality measurements, shown as reported. Water clarity: 3.1 m visibility. Phosphorus: 6.1 µg/L. Chlorophyll-a (algae): 10.5 µg/L. Maximum depth: 40.7 ft.
Is Iso Hietajärvi safe to swim in?: Iso Hietajärvi 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 Iso Hietajärvi?: Iso Hietajärvi has a maximum depth of 40.7 feet.

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Where this data comes from

10 measurements from 1 monitoring station, 2022. 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-vesla10 samples · 2022

Analytical methods

SYKE VESLA

Monitoring station identifiers (1)

36162

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