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

Cleanest Lakes in Middlesex County, Massachusetts

Ashby Reservoir in Middlesex County leads the rankings with a water quality grade of NR. Below are the top 50 cleanest monitored lakes in Middlesex County, Massachusetts, ranked by EPA water quality score.

Ranked List

#LakeCountyGradeClarityPhosphorusAlgae
1Ashby ReservoirMiddlesexNR---
2Harbor PondMiddlesexNR---
3Heald PondMiddlesexNR---
4Coon Tree PondMiddlesexNR---
5Nashua River ReservoirMiddlesexNR---
6Plow Shop PondMiddlesexNR---
7Eldridge PondMiddlesexNR---
8Grove PondMiddlesexNR---
9Sandy PondMiddlesexNR---
10Flannagan PondMiddlesexNR---
11Long PondMiddlesexNR---
12Spectacle PondMiddlesexNR---
13Long PondMiddlesexNR---
14Fort PondMiddlesexNR---
15Nagog PondMiddlesexNR---
16Cramberry Bog Reservoir Number OneMiddlesexNR---
17Russell MillpondMiddlesexNR---
18Batemans PondMiddlesexNR---
19Warners PondMiddlesexNR---
20White PondMiddlesexNR---
21Fairhaven BayMiddlesexNR---
22Flints PondMiddlesexNR---
23Walden PondMiddlesexNR---
24Lower Mystic LakeMiddlesexNR---
25Upper Mystic LakeMiddlesexNR---
26North ReservoirMiddlesexNR---
27Middle ReservoirMiddlesexNR---
28Spot PondMiddlesexNR---
29Crystal LakeMiddlesexNR---
30Mill Pond ReservoirMiddlesexNR---
31Nutting LakeMiddlesexNR---
32Richardson PondMiddlesexNR---
33Long PondMiddlesexNR---
34Ames PondMiddlesexNR---
35Martins PondMiddlesexNR---
36Swan PondMiddlesexNR---
37Peters PondMiddlesexNR---
38Flint PondMiddlesexNR---
39Althea LakeMiddlesexNR---
40Burges PondMiddlesexNR---
41Newfield PondMiddlesexNR---
42Fletchers PondMiddlesexNR---
43Long Sought-for PondMiddlesexNR---
44Keyes PondMiddlesexNR---
45Forge PondMiddlesexNR---
46Whitney PondMiddlesexNR---
47Lost LakeMiddlesexNR---
48Knops PondMiddlesexNR---
49Baddacook PondMiddlesexNR---
50Massapoag PondsMiddlesexNR---

More Answers for Middlesex County, Massachusetts

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