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LakeQuality

One Island Lake

Thunder Bay District, OntarioView mapDirections

Ontario MECP publishes the water-quality measurements for One Island Lake. Here is what has been measured.

Clarity
1.9 m
Secchi · sampled 2025
Phosphorus
8 µg/L
Measured by Ontario MECP

One Island Lake in Thunder Bay District, Ontario has water-quality measurements published by Ontario MECP, shown here as reported. Water clarity: 1.9 m visibility. Phosphorus: 8 µg/L.

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One Island Lake is a lake in Thunder Bay District County, Ontario.

Source: Ontario open-data programmes (Lake Partner Program and Broad-scale Monitoring) — not the EPA Water Quality Portal, last sampled 2025-05-22. Grade methodology: LakeQuality methodology.

Swimming conditions

No reading

Not rated

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

Whether One Island Lake is safe to swim in today is a call for the Ontario Ministry of the Environment, Conservation and Parks and the county health department, who post current advisories. LakeQuality does not issue swimming clearances.

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Water quality measurements for One Island Lake

These are the measurements Ontario MECP publishes for One Island Lake, shown as reported. The condition class beside each reading is the EPA National Lakes Assessment class for this lake’s ecoregion.

Murky, only visible to about 6.1 ft. Phosphorus 8 µg/L. TSI 43.

MetricValueEPA condition class
Water Clarity (Secchi Depth)1.85 mMeasured, not scored
Phosphorus8 µg/LMeasured, not scored
Chlorophyll-a (Algae)No recent samples
Trophic State Index (TSI)43Mesotrophic

Moderate nutrients, good water quality

Fishing One Island Lake

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Frequently asked questions about One Island Lake

Ask about One Island Lake

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

Where is One Island Lake?

One Island Lake is a lake in Thunder Bay District, Ontario. Its water-quality measurements are published by Ontario MECP and shown on this page as reported.

What is the water quality of One Island Lake?

One Island Lake in Thunder Bay District, Ontario has water-quality measurements published by Ontario MECP, shown here as reported. Water clarity: 1.9 m visibility. Phosphorus: 8 µg/L.

Is One Island Lake safe to swim in?

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

Where this data comes from

Measurements for One Island Lake come from Ontario open-data programmes (Lake Partner Program and Broad-scale Monitoring), not the EPA Water Quality Portal. Per-sample source details are not recorded for this lake. Contains information licensed under the Open Government Licence – Ontario. See data sources.