All Graded Lakes
Every monitored lake LakeQuality grades — 14,370 lakes across 38 states and 1,600 counties. Search for any lake by name, or browse by state, county, or grade.
Browse by Grade
10,087 of 14,370 lakes earn an A–F report card from water clarity, phosphorus, and algae data. 4,283 do not have enough monitoring data to grade.
Browse by State
All states →Lakes by country →Water quality report cards for every state we cover, sorted by number of graded lakes.
Ontario
2,822 lakes40 counties graded
Minnesota
2,394 lakes77 counties graded
Florida
2,159 lakes59 counties graded
Wisconsin
1,428 lakes69 counties graded
Québec
1,018 lakes70 counties graded
Michigan
646 lakes62 counties graded
Missouri
278 lakes77 counties graded
Vermont
228 lakes14 counties graded
Wyoming
220 lakes19 counties graded
Iowa
209 lakes76 counties graded
Kansas
196 lakes75 counties graded
New York
189 lakes48 counties graded
Montana
188 lakes13 counties graded
Virginia
175 lakes61 counties graded
Utah
168 lakes28 counties graded
Texas
164 lakes90 counties graded
Oklahoma
157 lakes60 counties graded
North Carolina
154 lakes58 counties graded
North Dakota
149 lakes48 counties graded
Illinois
148 lakes45 counties graded
Arkansas
137 lakes52 counties graded
Colorado
118 lakes49 counties graded
Kentucky
113 lakes75 counties graded
Alabama
110 lakes45 counties graded
Massachusetts
105 lakes12 counties graded
Oregon
99 lakes25 counties graded
Tennessee
76 lakes42 counties graded
Arizona
75 lakes14 counties graded
New Mexico
73 lakes22 counties graded
Nebraska
69 lakes49 counties graded
Nevada
56 lakes12 counties graded
Washington
56 lakes18 counties graded
Georgia
56 lakes35 counties graded
Ohio
52 lakes28 counties graded
Idaho
50 lakes17 counties graded
Indiana
22 lakes7 counties graded
South Dakota
9 lakes5 counties graded
Pennsylvania
4 lakes4 counties graded
Browse by County
All 1,600 counties ranked by average lake water quality — find the cleanest lake counties for a cabin, a fishing trip, or a move.
View county rankings →Cleanest Lakes Right Now
The top-graded lakes across all 38 states. See the full ranking →
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