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

Washington County Lake Quality

Idaho, 9 lakes, measured by Idaho DEQ

Washington County holds 9 monitored lakes. With a sample that small the county-level summary describes those specific waters, not necessarily every water body in the county. The 9 monitored lakes in Washington County carry whatever clarity, phosphorus, and chlorophyll-a readings Idaho DEQ 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 Washington County

Top-rated places to stay near Washington County

Prices for Oct 30–Nov 1, 4 adults. Change dates on the map below.

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Quick Answers for Washington County

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

Planning a trip? Check special fishing regulations for Mann Creek Reservoir — or check the official Idaho fishing regulations.

All Lakes in Washington County

9 lakes · 0 ranked on readings, 9 without enough sampling0 lakes ranked on readings · 9 without enough sampling, hidden

#LakeClarityPhosphorusAlgaeTrophicMax DepthAccess
Mann Creek ReservoirWashingtonNo recent samples49 µg/L179 µg/LNo recent samplesNo recent samplesNot recorded
Crane Creek ReservoirWashingtonNo recent samplesNo recent samplesNo recent samplesNo recent samplesNo recent samples✓ Public
Little Crane Creek ReservoirWashingtonNo recent samplesNo recent samplesNo recent samplesNo recent samplesNo recent samplesNot recorded
Fairchild ReservoirWashingtonNo recent samplesNo recent samplesNo recent samplesNo recent samplesNo recent samplesNot recorded
Mann Creek ReservoirWashingtonNo recent samplesNo recent samplesNo recent samplesNo recent samples123 ft✓ Public
Barton ReservoirWashingtonNo recent samplesNo recent samplesNo recent samplesNo recent samplesNo recent samplesNot recorded
Buttermilk SloughWashingtonNo recent samplesNo recent samplesNo recent samplesNo recent samplesNo recent samplesNot recorded
Paddock Valley ReservoirWashingtonNo recent samplesNo recent samplesNo recent samplesNo recent samplesNo recent samplesNot recorded
Soulen ReservoirWashingtonNo recent samplesNo recent samplesNo recent samplesNo recent samplesNo recent samplesNot recorded

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 Idaho

Gem County

2 lakes

Canyon County

2 lakes

Bear Lake County

3 lakes

Valley County

26 lakes

Bonneville County

9 lakes

Blaine County

12 lakes

Browse every Idaho 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 Idaho Department of Environmental Quality. See data sources.