Late afternoon sun over Slim Lake, scattering a bright path across wind-textured water

Frontenac County Lake Quality

Ontario, 104 lakes, measured by Ontario MECP

Frontenac County in Ontario carries 104 monitored lakes — one of the lake-richer counties in our dataset. Coverage that dense usually reflects active lake-association sampling alongside state-agency monitoring. The 104 monitored lakes in Frontenac County carry whatever clarity, phosphorus, and chlorophyll-a readings Ontario MECP has published, shown as reported.

Most of the county's monitored lakes are shallow, under 50 feet, which means wind keeps the water column mixed all summer and sediment-bound phosphorus releases back into the surface layer whenever the bottom is disturbed.

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Planning a trip? Check special fishing regulations for Ardoch Lake — or check the official Ontario fishing regulations.

All Lakes in Frontenac County

104 lakes · 0 ranked on readings, 104 without enough sampling0 lakes ranked on readings · 104 without enough sampling, hidden

Include not-rated lakes (104)

Lake	Clarity	Phosphorus	Algae	Trophic	Access
Ardoch LakeFrontenac	19 ft	6.8 µg/L	No recent samples	No recent samples	Not recorded
Big Clear LakeFrontenac	15.1 ft	9 µg/L	No recent samples	No recent samples	Not recorded
Big Clear LakeFrontenac	21.3 ft	8.1 µg/L	No recent samples	No recent samples	Not recorded
Big Gull LakeFrontenac	13.1 ft	8.1 µg/L	No recent samples	No recent samples	Not recorded
Big Olhman LakeFrontenac	16.4 ft	13.8 µg/L	No recent samples	No recent samples	Not recorded
Birch LakeFrontenac	14.1 ft	8.8 µg/L	No recent samples	No recent samples	Not recorded
Blue LakeFrontenac	37.7 ft	8.1 µg/L	No recent samples	No recent samples	Not recorded
Bobs LakeFrontenac	15.7 ft	9.3 µg/L	No recent samples	No recent samples	Not recorded
Brule LakeFrontenac	23.3 ft	5.4 µg/L	No recent samples	No recent samples	Not recorded
Buck LakeFrontenac	13.1 ft	9.7 µg/L	No recent samples	No recent samples	Not recorded
Buckshot LakeFrontenac	13.5 ft	5.1 µg/L	No recent samples	No recent samples	Not recorded
Buffy LakeFrontenac	9.2 ft	21 µg/L	No recent samples	No recent samples	Not recorded
Burridge LakeFrontenac	17.2 ft	9 µg/L	No recent samples	No recent samples	Not recorded
Butterill LakeFrontenac	14.4 ft	14.1 µg/L	No recent samples	No recent samples	Not recorded
Canoe LakeFrontenac	14.1 ft	7.9 µg/L	No recent samples	No recent samples	Not recorded
Canonto LakeFrontenac	20 ft	6.2 µg/L	No recent samples	No recent samples	Not recorded
Carnahan LakeFrontenac	10.5 ft	19 µg/L	No recent samples	No recent samples	Not recorded
Cole LakeFrontenac	5.9 ft	18.5 µg/L	No recent samples	No recent samples	Not recorded
Collins LakeFrontenac	8.5 ft	18 µg/L	No recent samples	No recent samples	Not recorded
Cox'S LakeFrontenac	7.5 ft	9.6 µg/L	No recent samples	No recent samples	Not recorded
Cranberry LakeFrontenac	8.9 ft	18.5 µg/L	No recent samples	No recent samples	Not recorded
Crotch LakeFrontenac	8.5 ft	10.5 µg/L	No recent samples	No recent samples	Not recorded
Crotch LakeFrontenac	13.1 ft	7.7 µg/L	No recent samples	No recent samples	Not recorded
Crow LakeFrontenac	17.4 ft	7 µg/L	No recent samples	No recent samples	Not recorded
Desert LakeFrontenac	19 ft	9.1 µg/L	No recent samples	No recent samples	Not recorded
Devil LakeFrontenac	21.3 ft	7.4 µg/L	No recent samples	No recent samples	Not recorded
Dog LakeFrontenac	6.2 ft	28.1 µg/L	No recent samples	No recent samples	Not recorded
Eagle LakeFrontenac	17.9 ft	8.5 µg/L	No recent samples	No recent samples	Not recorded
Elbow LakeFrontenac	9.8 ft	14.8 µg/L	No recent samples	No recent samples	Not recorded
Fawn LakeFrontenac	12.3 ft	No recent samples	No recent samples	No recent samples	Not recorded
Fermoy LakeFrontenac	11.3 ft	13.5 µg/L	No recent samples	No recent samples	Not recorded
Fishing LakeFrontenac	13.1 ft	10.1 µg/L	No recent samples	No recent samples	Not recorded
Fortune LakeFrontenac	27.9 ft	No recent samples	No recent samples	No recent samples	Not recorded
Fourteen Island LakeFrontenac	21.3 ft	11.4 µg/L	No recent samples	No recent samples	Not recorded
Garter LakeFrontenac	16.7 ft	No recent samples	No recent samples	No recent samples	Not recorded
Gould LakeFrontenac	18 ft	6.7 µg/L	No recent samples	No recent samples	Not recorded
Green LakeFrontenac	21.2 ft	5.2 µg/L	No recent samples	No recent samples	Not recorded
Grindstone LakeFrontenac	18 ft	4.9 µg/L	No recent samples	No recent samples	Not recorded
Guerley LakeFrontenac	13.1 ft	14.5 µg/L	No recent samples	No recent samples	Not recorded
Hambly LakeFrontenac	14.6 ft	10.2 µg/L	No recent samples	No recent samples	Not recorded
Horseshoe LakeFrontenac	9.8 ft	8.5 µg/L	No recent samples	No recent samples	Not recorded
Howes LakeFrontenac	12.8 ft	17.3 µg/L	No recent samples	No recent samples	Not recorded
Hungry LakeFrontenac	7.9 ft	6.7 µg/L	No recent samples	No recent samples	Not recorded
Inverary LakeFrontenac	5.9 ft	19.1 µg/L	No recent samples	No recent samples	Not recorded
Kashwakamak LakeFrontenac	15.7 ft	7.2 µg/L	No recent samples	No recent samples	Not recorded
Kennebec LakeFrontenac	8.9 ft	9.6 µg/L	No recent samples	No recent samples	Not recorded
Knowlton LakeFrontenac	13.1 ft	8.2 µg/L	No recent samples	No recent samples	Not recorded
Leggat LakeFrontenac	22.6 ft	No recent samples	No recent samples	No recent samples	Not recorded
Little Long LakeFrontenac	14.9 ft	9.7 µg/L	No recent samples	No recent samples	Not recorded
Long LakeFrontenac	11.2 ft	15.2 µg/L	No recent samples	No recent samples	Not recorded
Long Schooner LakeFrontenac	20.2 ft	16.4 µg/L	No recent samples	No recent samples	Not recorded
Loughborough LakeFrontenac	13.1 ft	11.7 µg/L	No recent samples	No recent samples	Not recorded
Lower Rock LakeFrontenac	16.1 ft	8.3 µg/L	No recent samples	No recent samples	Not recorded
Lucky LakeFrontenac	21.3 ft	8.2 µg/L	No recent samples	No recent samples	Not recorded
Mackie LakeFrontenac	19 ft	5.3 µg/L	No recent samples	No recent samples	Not recorded
Malcolm LakeFrontenac	14.8 ft	9.4 µg/L	No recent samples	No recent samples	Not recorded
Mazinaw LakeFrontenac	16.1 ft	4.3 µg/L	No recent samples	No recent samples	Not recorded
Milk LakeFrontenac	20.7 ft	11.6 µg/L	No recent samples	No recent samples	Not recorded
Mink LakeFrontenac	9.2 ft	8.5 µg/L	No recent samples	No recent samples	Not recorded
Mississagagon LakeFrontenac	23 ft	6.3 µg/L	No recent samples	No recent samples	Not recorded
Mosque LakeFrontenac	16.1 ft	6.4 µg/L	No recent samples	No recent samples	Not recorded
North Otter LakeFrontenac	14.1 ft	10.3 µg/L	No recent samples	No recent samples	Not recorded
Opinicon LakeFrontenac	13.1 ft	13.6 µg/L	No recent samples	No recent samples	Not recorded
O'Reilly LakeFrontenac	20 ft	No recent samples	No recent samples	No recent samples	Not recorded
Palmerston LakeFrontenac	21.3 ft	4.8 µg/L	No recent samples	No recent samples	Not recorded
Penyck LakeFrontenac	11.5 ft	13 µg/L	No recent samples	No recent samples	Not recorded
Pine LakeFrontenac	16.4 ft	6.5 µg/L	No recent samples	No recent samples	Not recorded
Pot LakeFrontenac	3.6 ft	28.4 µg/L	No recent samples	No recent samples	Not recorded
Potspoon LakeFrontenac	17.1 ft	11.3 µg/L	No recent samples	No recent samples	Not recorded
Rock LakeFrontenac	5.9 ft	12.6 µg/L	No recent samples	No recent samples	Not recorded
Round Schooner LakeFrontenac	16.4 ft	8.7 µg/L	No recent samples	No recent samples	Not recorded
Shabomeka LakeFrontenac	14.4 ft	No recent samples	No recent samples	No recent samples	Not recorded
Sharbot LakeFrontenac	17.1 ft	8.9 µg/L	No recent samples	No recent samples	Not recorded
Shawenegog LakeFrontenac	15.4 ft	6.7 µg/L	No recent samples	No recent samples	Not recorded
Sigsworth LakeFrontenac	16.4 ft	9.1 µg/L	No recent samples	No recent samples	Not recorded
Silver LakeFrontenac	20 ft	6.3 µg/L	No recent samples	No recent samples	Not recorded
St Andrew LakesFrontenac	11.8 ft	13.4 µg/L	No recent samples	No recent samples	Not recorded
Sunday LakeFrontenac	15.3 ft	8 µg/L	No recent samples	No recent samples	Not recorded
Swaugers LakeFrontenac	12.1 ft	9.3 µg/L	No recent samples	No recent samples	Not recorded
Sydenham LakeFrontenac	15.7 ft	12.3 µg/L	No recent samples	No recent samples	Not recorded
Thirteen Island LakeFrontenac	15.1 ft	12.5 µg/L	No recent samples	No recent samples	Not recorded
Thirty Island LakeFrontenac	18.7 ft	10.5 µg/L	No recent samples	No recent samples	Not recorded
Turtle LakeFrontenac	14.8 ft	11.1 µg/L	No recent samples	No recent samples	Not recorded
Unnamed LakeFrontenac	7.7 ft	23.4 µg/L	No recent samples	No recent samples	Not recorded
Unnamed LakeFrontenac	3.9 ft	35.2 µg/L	No recent samples	No recent samples	Not recorded
Upper Rock LakeFrontenac	11.2 ft	12 µg/L	No recent samples	No recent samples	Not recorded
White LakeFrontenac	11.5 ft	7.5 µg/L	No recent samples	No recent samples	Not recorded
Wolfe LakeFrontenac	20 ft	9.9 µg/L	No recent samples	No recent samples	Not recorded
Cranberry LakeFrontenac	No recent samples	11.7 µg/L	No recent samples	No recent samples	Not recorded
Darling LakeFrontenac	No recent samples	12.8 µg/L	No recent samples	No recent samples	Not recorded
Garrison LakeFrontenac	No recent samples	10.2 µg/L	No recent samples	No recent samples	Not recorded
Horseshoe LakeFrontenac	No recent samples	12 µg/L	No recent samples	No recent samples	Not recorded
Spring LakeFrontenac	No recent samples	12.1 µg/L	No recent samples	No recent samples	Not recorded
Warrens LakeFrontenac	No recent samples	10.9 µg/L	No recent samples	No recent samples	Not recorded
Black LakeFrontenac	No recent samples	15.4 µg/L	No recent samples	No recent samples	Not recorded
Belmont LakeFrontenac	10.5 ft	8.9 µg/L	No recent samples	No recent samples	Not recorded
Big Salmon LakeFrontenac	13.1 ft	8.1 µg/L	No recent samples	No recent samples	Not recorded
Bull LakeFrontenac	7.5 ft	10.1 µg/L	No recent samples	No recent samples	Not recorded
Fourth Depot LakeFrontenac	7.2 ft	11.9 µg/L	No recent samples	No recent samples	Not recorded
Govan LakeFrontenac	17.2 ft	15.6 µg/L	No recent samples	No recent samples	Not recorded
Kishkebus LakeFrontenac	10.5 ft	6.1 µg/L	No recent samples	No recent samples	Not recorded
Little Clear LakeFrontenac	6.9 ft	16.6 µg/L	No recent samples	No recent samples	Not recorded
Little John LakeFrontenac	14.4 ft	19.2 µg/L	No recent samples	No recent samples	Not recorded
St Andrews LakeFrontenac	11.5 ft	14.3 µg/L	No recent samples	No recent samples	Not recorded

NR = no nutrient or algae reading on record. The measurements are published as the authority reports them. Where the data comes from.

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Source: the Ontario Ministry of the Environment, Conservation and Parks. See data sources.