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

Mason County Lake Quality

Washington, 28 lakes, measured by Washington Ecology

The county-level average smooths over real differences — a single agricultural watershed near the southwest corner can pull the average down even if the rest of the county runs clean. The 28 monitored lakes in Mason County carry whatever clarity, phosphorus, and chlorophyll-a readings Washington Ecology 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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Where to stay near Mason County

Top-rated places to stay near Mason County

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Quick Answers for Mason County

Cleanest lakes in Mason County →Best swimming lakes in Washington →

Planning a trip? Check special fishing regulations for Mildred Lakes — or check the official Washington fishing regulations.

All Lakes in Mason County

28 lakes · 0 ranked on readings, 28 without enough sampling0 lakes ranked on readings · 28 without enough sampling, hidden

#LakeClarityPhosphorusAlgaeTrophicMax DepthAccess
Mildred LakesMasonNo recent samplesNo recent samplesNo recent samplesNo recent samplesNo recent samplesNot recorded
Island LakeMasonNo recent samplesNo recent samplesNo recent samplesNo recent samples30 ft✓ Public
Cranberry LakeMasonNo recent samplesNo recent samplesNo recent samplesNo recent samplesNo recent samplesNot recorded
Lake LimerickMasonNo recent samplesNo recent samplesNo recent samplesNo recent samplesNo recent samples✓ Public
Lake KokaneeMasonNo recent samplesNo recent samplesNo recent samplesNo recent samplesNo recent samplesNot recorded
Lake CushmanMasonNo recent samplesNo recent samplesNo recent samplesNo recent samplesNo recent samples✓ Public
Melbourne LakeMasonNo recent samplesNo recent samplesNo recent samplesNo recent samplesNo recent samplesNot recorded
Lake WootenMasonNo recent samplesNo recent samplesNo recent samplesNo recent samplesNo recent samples✓ Public
Haven LakeMasonNo recent samplesNo recent samplesNo recent samplesNo recent samplesNo recent samples✓ Public
Tee LakeMasonNo recent samplesNo recent samplesNo recent samplesNo recent samplesNo recent samples✓ Public
Bennettsen LakeMasonNo recent samplesNo recent samplesNo recent samplesNo recent samplesNo recent samplesNot recorded
Blacksmith LakeMasonNo recent samplesNo recent samplesNo recent samplesNo recent samplesNo recent samplesNot recorded
Tiger LakeMasonNo recent samplesNo recent samplesNo recent samplesNo recent samplesNo recent samples✓ Public
Lake AndersonMasonNo recent samplesNo recent samplesNo recent samplesNo recent samplesNo recent samplesNot recorded
Devereaux LakeMasonNo recent samplesNo recent samplesNo recent samplesNo recent samplesNo recent samples✓ Public
Prickett LakeMasonNo recent samplesNo recent samplesNo recent samplesNo recent samplesNo recent samplesNot recorded
Mason LakeMasonNo recent samplesNo recent samplesNo recent samplesNo recent samples90 ftNot recorded
Benson LakeMasonNo recent samplesNo recent samplesNo recent samplesNo recent samplesNo recent samples✓ Public
Spencer LakeMasonNo recent samplesNo recent samplesNo recent samplesNo recent samplesNo recent samples✓ Public
Phillips LakeMasonNo recent samplesNo recent samplesNo recent samplesNo recent samplesNo recent samples✓ Public
Forbes LakeMasonNo recent samplesNo recent samplesNo recent samplesNo recent samplesNo recent samplesNot recorded
Big Twin LakeMasonNo recent samplesNo recent samplesNo recent samplesNo recent samplesNo recent samplesNot recorded
Isabella LakeMasonNo recent samplesNo recent samplesNo recent samplesNo recent samplesNo recent samples✓ Public
Stump LakeMasonNo recent samplesNo recent samplesNo recent samplesNo recent samplesNo recent samplesNot recorded
Lost LakeMasonNo recent samplesNo recent samplesNo recent samplesNo recent samples60 ft✓ Public
Lystair LakeMasonNo recent samplesNo recent samplesNo recent samplesNo recent samplesNo recent samplesNot recorded
Lake ArrowheadMasonNo recent samplesNo recent samplesNo recent samplesNo recent samplesNo recent samplesNot recorded
Nahwatzel LakeMasonNo recent samplesNo recent samplesNo recent samplesNo recent samples24 ft✓ Public

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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Other Counties in Washington

Lincoln County

22 lakes

Grant County

48 lakes

Whatcom County

34 lakes

Yakima County

23 lakes

Snohomish County

52 lakes

Thurston County

29 lakes

Browse every Washington lake, or the full directory of lakes across all United States (49 states), Canada (Ontario, Québec, Nova Scotia, British Columbia and Newfoundland and Labrador), and 38 other country hubs..

Source: the Washington State Department of Ecology. See data sources.