Greenwater Lake
Thunder Bay District, OntarioView mapDirections
Ontario MECP publishes the water-quality measurements for Greenwater Lake. Here is what has been measured.
Greenwater Lake in Thunder Bay District, Ontario has water-quality measurements published by Ontario MECP, shown here as reported. Water clarity: 14.6 m visibility. Phosphorus: 1.8 µg/L.
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Greenwater 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 2025-08-01. Grade methodology: LakeQuality methodology.
What Greenwater Lake is good for
From access and monitoring records, not editorial picks.
- Clear water47.9 ft of visibility
Swimming conditions
No readingNot rated
Nutrient and algae readings are not a swimming clearance. Check local advisories before you swim.
Whether Greenwater 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.
Water quality measurements for Greenwater Lake
These are the measurements Ontario MECP publishes for Greenwater Lake, shown as reported. The condition class beside each reading is the EPA National Lakes Assessment class for this lake’s ecoregion.
Crystal clear, you can see 47.9 ft down. Phosphorus 1.8 µg/L. TSI 17.
| Metric | Value | EPA condition class |
|---|---|---|
| Water Clarity (Secchi Depth) | 14.6 m | Measured, not scored |
| Phosphorus | 1.8 µg/L | Measured, not scored |
| Chlorophyll-a (Algae) | No recent samples | |
| Trophic State Index (TSI) | 17 | Oligotrophic |
Low nutrients, clear water. No reading is a swimming clearance.
Lake Size & Watershed
Size, shoreline, and watershed area from HydroLAKES (HydroSHEDS).
Fishing Greenwater Lake
Nearby Lakes in Thunder Bay District
Frequently asked questions about Greenwater Lake
Ask about Greenwater Lake
Answers come straight from the public measurements and survey records on this page.
Where is Greenwater Lake?
- Greenwater 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 Greenwater Lake?
- Greenwater Lake in Thunder Bay District, Ontario has water-quality measurements published by Ontario MECP, shown here as reported. Water clarity: 14.6 m visibility. Phosphorus: 1.8 µg/L.
Is Greenwater Lake safe to swim in?
- Nutrient and algae readings are not a swimming clearance. Check local advisories before you swim.
How deep is Greenwater Lake?
- The available depth estimate for Greenwater Lake is shallower than its measured water clarity, which cannot be right, so no depth is shown.
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Where this data comes from
Measurements for Greenwater 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.
Other records on this page
Lake size & watershed from HydroLAKES (HydroSHEDS)