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LakeQuality

Nummijärvi

Lohja, FinlandView mapDirections

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

Clarity
2 m
Typical for Finland
Secchi · sampled 2024
Phosphorus
17 µg/L
Typical for Finland
Measured by Syke
Chlorophyll-a
12 µg/L
Typical for Finland
Measured by Syke
Max depth
15.1 m
Bathymetric survey
  • 50 ft max depth
  • Limited data

Nummijärvi in Lohja, Finland has official water-quality measurements, shown as reported. Water clarity: 2 m visibility. Phosphorus: 17 µg/L. Chlorophyll-a (algae): 12 µg/L. Maximum depth: 49.5 ft.

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How Nummijärvi is classified

Nummijärvi 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.

Nummijärvi is a lake in Lohja County, Finland with a maximum depth of 50 feet.

Source: the Finnish Environment Institute (Syke) and the ELY Centres — not the EPA Water Quality Portal, last sampled 2024-07-22. Methodology: how these readings are compared.

What Nummijärvi is good for

From access and monitoring records, not editorial picks.

  • Deep water49.5 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 Nummijärvi 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 Nummijärvi

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

Murky, only visible to about 6.6 ft. Phosphorus 17 µg/L. Chlorophyll-a 12 µg/L. TSI 50.

Water quality readings
MeasureReadingWhere it sits
Water clarity (Secchi depth)2mMeasured, 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)12µg/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 Nummijärvi

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

Lake Details

Max depth

15.1 m

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Fishing Nummijärvi

Frequently asked questions about Nummijärvi

Where is Nummijärvi?

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

What is the water quality of Nummijärvi?

Nummijärvi in Lohja, Finland has official water-quality measurements, shown as reported. Water clarity: 2 m visibility. Phosphorus: 17 µg/L. Chlorophyll-a (algae): 12 µg/L. Maximum depth: 49.5 ft.

Measurements on this page ↑

Is Nummijärvi safe to swim in?

Nummijärvi 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 Nummijärvi?

Nummijärvi has a maximum depth of 49.5 feet.

Where this data comes from

39 measurements from 3 monitoring stations, 2016–2024. 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-vesla39 samples · 2016–2024

Analytical methods

  • SYKE VESLA
Monitoring station identifiers (3)
  • 1570
  • 54834
  • 82007

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