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

Clark County Lake Quality

Washington, 16 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 16 monitored lakes in Clark 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 Clark County

Top-rated places to stay near Clark County

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Quick Answers for Clark County

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

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

All Lakes in Clark County

16 lakes · 0 ranked on readings, 16 without enough sampling0 lakes ranked on readings · 16 without enough sampling, hidden

#LakeClarityPhosphorusAlgaeTrophicMax DepthAccess
Vancouver LakeClark1.4 ft80 µg/L28.6 µg/LNo recent samplesNo recent samplesNot recorded
Lacamas LakeClark4.4 ftNo recent samplesNo recent samplesNo recent samplesNo recent samples✓ Public
Horseshoe LakeClarkNo recent samplesNo recent samplesNo recent samplesNo recent samplesNo recent samples✓ Public
Lake RosannahClarkNo recent samplesNo recent samplesNo recent samplesNo recent samplesNo recent samplesNot recorded
Lancaster LakeClarkNo recent samplesNo recent samplesNo recent samplesNo recent samplesNo recent samplesNot recorded
Widgeon LakeClarkNo recent samplesNo recent samplesNo recent samplesNo recent samplesNo recent samplesNot recorded
Canvasback LakeClarkNo recent samplesNo recent samplesNo recent samplesNo recent samplesNo recent samplesNot recorded
Lancaster LakeClarkNo recent samplesNo recent samplesNo recent samplesNo recent samplesNo recent samplesNot recorded
Carty LakeClarkNo recent samplesNo recent samplesNo recent samplesNo recent samplesNo recent samplesNot recorded
Campbell LakeClarkNo recent samplesNo recent samplesNo recent samplesNo recent samplesNo recent samplesNot recorded
Green LakeClarkNo recent samplesNo recent samplesNo recent samplesNo recent samplesNo recent samplesNot recorded
Post Office LakeClarkNo recent samplesNo recent samplesNo recent samplesNo recent samplesNo recent samplesNot recorded
Battle Ground LakeClarkNo recent samplesNo recent samplesNo recent samplesNo recent samplesNo recent samplesNot recorded
Round LakeClarkNo recent samplesNo recent samplesNo recent samplesNo recent samples64 ftNot recorded
Yale LakeClarkNo recent samplesNo recent samplesNo recent samplesNo recent samplesNo recent samples✓ Public
Lake MerwinClarkNo recent samplesNo recent samplesNo recent samplesNo recent samples186 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.