Grade C Lakes, Fair

1,345 lakes (9% of lakes we track)

C is a common bracket: productive, swimmable most days, with the occasional July week where blooms make the water unappealing. 1,345 lakes grade C. Clarity is measured and shown; it is not why the letter landed here.

A B C D F

1,345

Grade C lakes

States in this list

MN 75QC 25

Lake	County	State	Clarity	Depth	Fish
Lac Denison	Le Val-Saint-François	QC	5.2 ft	-	0
Lac Pierre-Paul	Mékinac	QC	5.9 ft	-	0
Lac Aux Ours	Les Laurentides	QC	4.6 ft	-	0
Lac MéNard	Les Laurentides	QC	3.8 ft	-	0
RéServoir ChoinièRe	La Haute-Yamaska	QC	5.6 ft	-	0
Lac du Village	Urban agglomeration of Longueuil	QC	8.2 ft	-	0
Lac Arbour	Matawinie	QC	4.3 ft	-	0
Lac Schryer	Les Pays-d'en-Haut	QC	4.1 ft	-	0
Petit Lac Noir	Antoine-Labelle	QC	5.2 ft	-	0
Lac des Chicots	Mékinac	QC	4.9 ft	-	0
Lac Johanne	Les Pays-d'en-Haut	QC	3.4 ft	-	0
Lac Boivin	La Haute-Yamaska	QC	7.5 ft	-	0
Lac Rouyn	Abitibi-Témiscamingue	QC	8.2 ft	-	0
Lac Ouellette	Antoine-Labelle	QC	6.4 ft	-	0
Lac des Bleuets	Saguenay–Lac-Saint-Jean	QC	5.6 ft	-	0
Lac Aux Grelots	Beauce-Sartigan	QC	4.3 ft	-	0
Petit Lac Dufresnoy	Abitibi-Témiscamingue	QC	3.3 ft	-	0
Lac de Saint-Damase	La Matapédia	QC	4.6 ft	-	0
Lac Michaud	La Matapédia	QC	5.2 ft	-	0
Lac Bolduc	Les Appalaches	QC	4.1 ft	-	0
Lac Frederic	Argenteuil	QC	5.6 ft	-	0
Lac Bibeau	Matawinie	QC	4.3 ft	-	0
Lac Joseph	L'Érable	QC	4.9 ft	-	0
Lac la Motte	Abitibi	QC	2.3 ft	-	0
Lac William	L'Érable	QC	6.2 ft	-	0
Minnetonka Lake	Hennepin	MN	10 ft	113 ft	18
Big Birch Lake	Todd	MN	12.5 ft	81 ft	18
Mud Lake	Wright	MN	5.6 ft	65 ft	15
Big Lake	Stearns	MN	6.9 ft	42 ft	16
Birch Lake	St. Louis	MN	3.9 ft	25 ft	10
Round Lake	Hennepin	MN	6.6 ft	37 ft	8
Horseshoe Lake	Chisago	MN	4.6 ft	53 ft	14
Horseshoe Lake	Dakota	MN	6.7 ft	-	0
Long Lake	Todd	MN	10.1 ft	63 ft	16
Long Lake	Washington	MN	8 ft	25 ft	0
Long Lake	Meeker	MN	7.5 ft	28 ft	12
Unnamed Lake	Dakota	MN	6 ft	-	3
Maple Lake	Polk	MN	3.3 ft	14 ft	12
Twin Lake	Ramsey	MN	7.5 ft	33 ft	8
Bryant Lake	Hennepin	MN	9.8 ft	45 ft	11
Lemay Lake	Dakota	MN	6.9 ft	15.5 ft	8
Otter Lake	Stearns	MN	9 ft	51 ft	13
Mccarron Lake	Ramsey	MN	11.5 ft	57 ft	13
Pirz Lake	Stearns	MN	12 ft	-	0
Upper South Long Lake	Crow Wing	MN	6 ft	47 ft	16
Clear Lake	Washington	MN	6.2 ft	28 ft	14
One Pine Lake	St. Louis	MN	4.5 ft	13 ft	13
Kraemer Lake	Stearns	MN	6.9 ft	30 ft	14
Blue Lake	Scott	MN	1.9 ft	50 ft	11
Eagle Lake	Crow Wing	MN	9.5 ft	-	0
Auburn Lake	Carver	MN	6.4 ft	84 ft	14
Johanna Lake	Pope	MN	5.1 ft	10 ft	11
Fish Lake	Jackson	MN	4.5 ft	-	0
Fish Lake	Dakota	MN	7.2 ft	33.5 ft	7
Fish Lake	Hennepin	MN	8.2 ft	49 ft	16
Fish Lake	Le Sueur	MN	11.8 ft	55 ft	14
Fish Lake	Washington	MN	5 ft	-	0
Washington Lake	Meeker	MN	4.5 ft	17 ft	18
Sand Lake	Carlton	MN	5 ft	27 ft	3
Sand Lake	Lake	MN	4.1 ft	11 ft	9
Little Pine Lake	Otter Tail	MN	9.5 ft	63 ft	20
Irving Lake	Beltrami	MN	5.6 ft	19 ft	20
Union Lake	Wright	MN	5.5 ft	35 ft	15
Allie Lake	Renville	MN	3 ft	12 ft	13
Green Lake	Chisago	MN	6 ft	32 ft	15
Grace Lake	Beltrami	MN	15 ft	42 ft	13
Bass Lake	Becker	MN	7.9 ft	28 ft	9
Bass Lake	Washington	MN	6.5 ft	-	0
Bass Lake	Otter Tail	MN	8.5 ft	36 ft	7
Island Lake	Itasca	MN	8.9 ft	35 ft	15
Crooked Lake	Anoka	MN	7.1 ft	26 ft	12
Portage Lake	Hubbard	MN	5.5 ft	17 ft	12
Portage Lake	Cass	MN	7.5 ft	55 ft	15
Big Pine Lake	Otter Tail	MN	8.7 ft	76 ft	20
Blackhawk Lake	Dakota	MN	7.9 ft	12 ft	7
Mitchell Lake	Crow Wing	MN	7 ft	78 ft	18
Sandy Lake	Beltrami	MN	10.7 ft	72 ft	10
Pickerel Lake	Itasca	MN	10.2 ft	70 ft	13
George Lake	Stearns	MN	7.3 ft	32 ft	8
George Lake	Cass	MN	5 ft	20 ft	11
George Lake	Anoka	MN	7.3 ft	32 ft	12
Arrowhead Lake	Crow Wing	MN	6.9 ft	13 ft	16
Gull Lake	Beltrami	MN	7.9 ft	23 ft	13
Koronis Lake	Stearns	MN	6 ft	132 ft	22
Bingham Lake	Cottonwood	MN	4 ft	10 ft	8
Upper Red Lake: West-Central	Beltrami	MN	2 ft	15 ft	15
Phalen Lake	Ramsey	MN	8.1 ft	91 ft	11
Skogman Lake	Isanti	MN	5.4 ft	36 ft	12
Goose Lake	Chisago	MN	4.5 ft	55 ft	15
Roy Lake	Mahnomen	MN	6 ft	16 ft	13
Sand Hill Lake	Polk	MN	6.9 ft	17 ft	6
Rock Lake	Cass	MN	5.9 ft	17 ft	11
Minnewawa Lake	Aitkin	MN	5 ft	21 ft	15
Crystal Lake	Dakota	MN	7 ft	37 ft	13
Lower Red Lake : East Central	Beltrami	MN	4 ft	-	0
Mill Lake	Douglas	MN	11 ft	40 ft	15
Camelot Lake	Hennepin	MN	1.3 ft	31 ft	8
Big Sandy Lake	Aitkin	MN	4.5 ft	84 ft	22
Mary Lake	Crow Wing	MN	4.9 ft	34 ft	13
Mary Lake	Wright	MN	8.9 ft	46 ft	13

Showing 100 of 1,345 Grade C lakes.

Frequently Asked Questions

How many lakes have a grade of C?

There are 1,345 Grade C (Fair) lakes across the 49 states and 2 Canadian provinces LakeQuality covers. That is 9% of the 14,370 lakes we track. Lakes without enough recent nutrient or algae samples are published as Not Rated — they are not in this count and they are not an F.

What does a Grade C mean?

Grade C means nutrients and algae sit in the middle of the EPA condition scale for that ecoregion. Moderate algal pressure is common in late summer. Generally swimmable, but check advisories. Clarity is measured, not scored.

Featured Grade C Lakes

Lac Denison

Le Val-Saint-François County, QC · 5.2 ft clarity

Lac Pierre-Paul

Mékinac County, QC · 5.9 ft clarity

Lac Aux Ours

Les Laurentides County, QC · 4.6 ft clarity

Lac MéNard

Les Laurentides County, QC · 3.8 ft clarity

RéServoir ChoinièRe

La Haute-Yamaska County, QC · 5.6 ft clarity

Lac du Village

Urban agglomeration of Longueuil County, QC · 8.2 ft clarity

Source: EPA National Aquatic Resource Surveys, 2026.