Where is Herttuanjärvi?

Herttuanjärvi is a lake in Tammela, Finland. This page reports official water-quality measurements, shown as reported.

Is Herttuanjärvi safe to swim in?

Herttuanjärvi 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 Herttuanjärvi?

Herttuanjärvi has a maximum depth of 38.7 feet.

Herttuanjärvi

Tammela, FinlandView map Directions

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

Clarity

1.5 m

Typical for Finland

Secchi · sampled 2016

Phosphorus

17 µg/L

Typical for Finland

Measured by Syke

Chlorophyll-a

4.3 µg/L

Less algae than most

Measured by Syke

Max depth

11.8 m

Bathymetric survey

39 ft max depth
Limited data

See the measurements Directions Where to stay

Herttuanjärvi in Tammela, Finland has official water-quality measurements, shown as reported. Water clarity: 1.5 m visibility. Phosphorus: 17 µg/L. Chlorophyll-a (algae): 4.3 µg/L. Maximum depth: 38.7 ft.

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How Herttuanjärvi is classified

Herttuanjärvi 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.

Herttuanjärvi is a lake in Tammela County, Finland with a maximum depth of 39 feet.

Source: the Finnish Environment Institute (Syke) and the ELY Centres — not the EPA Water Quality Portal, last sampled 2016-08-17. Methodology: how these readings are compared.

What Herttuanjärvi is good for

From access and monitoring records, not editorial picks.

Deep water38.7 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 Herttuanjärvi 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 Herttuanjärvi

These are the measurements Syke publishes for Herttuanjärvi. More on the source.

Murky, only visible to about 4.9 ft. Phosphorus 17 µg/L. Chlorophyll-a 4.3 µg/L. TSI 48.

Water quality readings
Measure	Reading	Where it sits
Water clarity (Secchi depth)	1.5m	Measured, not scored How deep a black-and-white disk stays visible from the surface. Higher is clearer.
Total phosphorus	17µg/L	Measured, not scored The nutrient that most limits algae growth in freshwater. More phosphorus, more algae potential.
Chlorophyll-a (algae)	4.3µg/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.	48	Mesotrophic OligotrophicMesotrophicEutrophicHypereutrophic

Moderate nutrients, good water quality

Ask about Herttuanjärvi

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

Lake Details

Max depth

11.8 m

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Stays near Herttuanjärvi

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Fishing Herttuanjärvi

→ Herttuanjärvi fishing regulations (limits, seasons, special rules)

Frequently asked questions about Herttuanjärvi

Where is Herttuanjärvi?: Herttuanjärvi is a lake in Tammela, Finland. This page reports official water-quality measurements, shown as reported.
What is the water quality of Herttuanjärvi?: Herttuanjärvi in Tammela, Finland has official water-quality measurements, shown as reported. Water clarity: 1.5 m visibility. Phosphorus: 17 µg/L. Chlorophyll-a (algae): 4.3 µg/L. Maximum depth: 38.7 ft.
Is Herttuanjärvi safe to swim in?: Herttuanjärvi 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 Herttuanjärvi?: Herttuanjärvi has a maximum depth of 38.7 feet.

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Where this data comes from

3 measurements from 1 monitoring station, 2016. 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-vesla3 samples · 2016

Analytical methods

SYKE VESLA

Monitoring station identifiers (1)

2482

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