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

Cleanest Lakes in Colorado

Pueblo Reservoir in Pueblo County leads the rankings with a water quality grade of A and 6.5 ft of clarity. Below are the top 50 cleanest monitored lakes in Colorado, ranked by EPA water quality score.

Ranked List

#LakeCountyGradeClarityPhosphorusAlgae
1Pueblo ReservoirPuebloA6.5 ft15 µg/L4.9 µg/L
2Willow Creek ReservoirGrandC3.9 ft75.5 µg/L2.4 µg/L
3Wolford Mountain ReservoirGrandC7.5 ft13 µg/L2 µg/L
4Grand LakeGrandC8.7 ft14 µg/L2.7 µg/L
5Shadow Mountain LakeGrandD7.9 ft20 µg/L5.1 µg/L
6Blue Mesa ReservoirGunnisonD11.5 ft35 µg/L3.9 µg/L
7Dillon ReservoirSummitD11.6 ft46 µg/L2.8 µg/L
8Deweese ReservoirCusterD5.2 ft41.5 µg/L13.5 µg/L
9Windy Gap ReservoirGrandD-52 µg/L3 µg/L
10Horse Creek Outlet LakeWeldD-460 µg/L27.6 µg/L
11Stagecoach LakeRouttD-50 µg/L-
12Prospect LakeWeldF-300 µg/L42.5 µg/L
13McDonough ReservoirSaguacheNR---
14Davey LakeSaguacheNR---
15Harrence LakeSaguacheNR---
16Trites LakeSaguacheNR---
17Island LakeSaguacheNR---
18Mishak LakesSaguacheNR---
19Weisman LakeSaguacheNR---
20North Crestone LakeSaguacheNR---
21Upper Dome ReservoirSaguacheNR---
22Needle Creek ReservoirSaguacheNR---
23Upper Sand Creek LakeSaguacheNR---
24Julesburg ReservoirSedgwickNR---
25Logie LakeCheyenneNR---
26Brush Creek LakesCusterNR---
27Mormon ReservoirLa PlataNR---
28Pastorius ReservoirLa PlataNR---
29Chapman LakeLa PlataNR---
30Electra LakeLa PlataNR---
31Shalona LakeLa PlataNR---
32Lemon ReservoirLa PlataNR---
33Vallecito ReservoirLa PlataNR---
34City ReservoirLa PlataNR---
35Columbine LakeLa PlataNR---
36Balsam LakeSan JuanNR---
37Highland Mary LakesSan JuanNR---
38Clear LakeSan JuanNR---
39Columbine LakeSan JuanNR---
40Silver LakeSan JuanNR---
41Wildcat ReservoirPitkinNR---
42Snowmass LakePitkinNR---
43Grizzly ReservoirPitkinNR---
44Ivanhoe LakePitkinNR---
45Homestake ReservoirPitkinNR---
46Montgomery ReservoirParkNR---
47Jefferson LakeParkNR---
48Lininger LakeParkNR---
49Tarryall ReservoirParkNR---
50Milligan LakesParkNR---

More Answers for Colorado

Cleanest lakes →Safest swimming lakes →Lakes with algae →All Colorado lakes →

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