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LakeQuality

Rainbow Lake

Lanark, OntarioView mapDirections

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

Clarity
2.8 m
Typical for Ontario
Secchi · sampled 2016
Phosphorus
13.8 µg/L
More phosphorus than most
Measured by Ontario MECP

Rainbow Lake in Lanark, Ontario has water-quality measurements published by Ontario MECP, shown here as reported. Water clarity: 2.8 m visibility. Phosphorus: 13.8 µg/L.

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Rainbow 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 2016-05-23. Methodology: how these readings are compared.

Swimming conditions

No reading

Not rated

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

Whether Rainbow 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 Rainbow Lake

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

Moderate clarity, visible to about 9.2 ft. Phosphorus 13.8 µg/L. TSI 44.

Water quality readings
MeasureReadingWhere it sits
Water clarity (Secchi depth)2.8mMeasured, not scored

How deep a black-and-white disk stays visible from the surface. Higher is clearer.

Total phosphorus13.8µg/LMeasured, 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.44Mesotrophic
OligotrophicMesotrophicEutrophicHypereutrophic

Moderate nutrients, good water quality

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Frequently asked questions about Rainbow Lake

Where is Rainbow Lake?

Rainbow 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 Rainbow Lake?

Rainbow Lake in Lanark, Ontario has water-quality measurements published by Ontario MECP, shown here as reported. Water clarity: 2.8 m visibility. Phosphorus: 13.8 µg/L.

Measurements on this page ↑

Is Rainbow Lake safe to swim in?

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

Swimming on this page ↑

Where this data comes from

Measurements for Rainbow 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.