Iso-Jälä Lake
Siilinjärvi, FinlandView mapDirections
Syke publishes the water-quality measurements for Iso-Jälä Lake. Here is what has been measured.
- 158 ft max depth
- Limited data
Iso-Jälä Lake in Siilinjärvi, Finland has official water-quality measurements, shown as reported. Water clarity: 2.7 m visibility. Phosphorus: 12 µg/L. Maximum depth: 157.5 ft.
How Iso-Jälä Lake is classified
Iso-Jälä 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 and phosphorus, but not 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-Jälä Lake is a lake in Siilinjärvi County, Finland with a maximum depth of 158 feet.
Source: the Finnish Environment Institute (Syke) and the ELY Centres — not the EPA Water Quality Portal, last sampled 2026-03-18. Methodology: how these readings are compared.
What Iso-Jälä Lake is good for
From access and monitoring records, not editorial picks.
- Deep water157.5 ft surveyed max depth
Swimming conditions
No readingLimited data
Nutrient and algae readings are not a swimming clearance. Check local advisories before you swim.
Whether Iso-Jälä 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.
Water quality measurements for Iso-Jälä Lake
These are the measurements Syke publishes for Iso-Jälä Lake. More on the source.
Moderate clarity, visible to about 8.9 ft. Phosphorus 12 µg/L. TSI 43.
| Measure | Reading | Where it sits |
|---|---|---|
| Water clarity (Secchi depth) | 2.7m | Measured, not scored How deep a black-and-white disk stays visible from the surface. Higher is clearer. |
| Total phosphorus | 12µg/L | Measured, not scored The nutrient that most limits algae growth in freshwater. More phosphorus, more algae potential. |
| Chlorophyll-a (algae) | No reading 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-Jälä Lake
Answers come straight from the public measurements and survey records on this page.
Lake Details
Max depth
48 m
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Fishing Iso-Jälä Lake
Frequently asked questions about Iso-Jälä Lake
Where is Iso-Jälä Lake?
- Iso-Jälä Lake is a lake in Siilinjärvi, Finland. This page reports official water-quality measurements, shown as reported.
What is the water quality of Iso-Jälä Lake?
- Iso-Jälä Lake in Siilinjärvi, Finland has official water-quality measurements, shown as reported. Water clarity: 2.7 m visibility. Phosphorus: 12 µg/L. Maximum depth: 157.5 ft.
Is Iso-Jälä Lake safe to swim in?
- Iso-Jälä 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 Iso-Jälä Lake?
- Iso-Jälä Lake has a maximum depth of 157.5 feet.
Explore Iso-Jälä Lake across LakeQuality
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Where this data comes from
42 measurements from 2 monitoring stations, 2016–2026. 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-vesla42 samples · 2016–2026
Analytical methods
- SYKE VESLA
Monitoring station identifiers (2)
6750261123
Authority classifications are shown as the authority published them. See where the data comes from and data sources.