Rock Lake
Lanark, OntarioView mapDirections
Ontario MECP publishes the water-quality measurements for Rock Lake. Here is what has been measured.
Rock Lake in Lanark, Ontario has water-quality measurements published by Ontario MECP, shown here as reported. Water clarity: 3.5 m visibility. Phosphorus: 8.4 µg/L.
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Rock Lake is a lake in Lanark County, Ontario.
Source: Ontario open-data programmes (Lake Partner Program and Broad-scale Monitoring) — not the EPA Water Quality Portal, last sampled 2016-05-17. Grade methodology: LakeQuality methodology.
What Rock Lake is good for
From access and monitoring records, not editorial picks.
- Clear water11.5 ft of visibility
Swimming conditions
No readingNot rated
Nutrient and algae readings are not a swimming clearance. Check local advisories before you swim.
Whether Rock 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 Rock Lake
These are the measurements Ontario MECP publishes for Rock Lake, shown as reported. The condition class beside each reading is the EPA National Lakes Assessment class for this lake’s ecoregion.
Good clarity, visible to about 11.5 ft. Phosphorus 8.4 µg/L. TSI 38.
| Metric | Value | EPA condition class |
|---|---|---|
| Water Clarity (Secchi Depth) | 3.5 m | Measured, not scored |
| Phosphorus | 8.4 µg/L | Measured, not scored |
| Chlorophyll-a (Algae) | No recent samples | |
| Trophic State Index (TSI) | 38 | Oligotrophic |
Low nutrients, clear water. No reading is a swimming clearance.
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Frequently asked questions about Rock Lake
Ask about Rock Lake
Answers come straight from the public measurements and survey records on this page.
Where is Rock Lake?
- Rock Lake is a lake in Lanark, Ontario. Its water-quality measurements are published by Ontario MECP and shown on this page as reported.
What is the water quality of Rock Lake?
- Rock Lake in Lanark, Ontario has water-quality measurements published by Ontario MECP, shown here as reported. Water clarity: 3.5 m visibility. Phosphorus: 8.4 µg/L.
Is Rock Lake safe to swim in?
- Nutrient and algae readings are not a swimming clearance. Check local advisories before you swim.
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Where this data comes from
Measurements for Rock 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.