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

Hancock County Lake Quality

Iowa, 6 lakes, measured by Iowa DNR

Hancock County holds 6 monitored lakes. With a sample that small the county-level summary describes those specific waters, not necessarily every water body in the county. 2 of those lakes carry recent nutrient and algae readings. The county-level summary describes that subset, not every water body listed. The monitored lakes here are mostly shallow, productive basins where summer algae is common; each lake page shows its own readings beside the EPA condition class.

The county's lakes lean shallow, which makes the readings sensitive to wind, sediment-resuspension, and any nutrient inputs from the watershed. The cleanest measured lake is Crystal Lake Max Depth.

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All Lakes in Hancock County

6 lakes · 2 ranked on readings, 4 without enough sampling2 lakes ranked on readings · 4 without enough sampling, hidden

#LakeClarityPhosphorusAlgaeTrophicAccess
1Crystal Lake Max DepthHancock1.6 ft99 µg/L50.3 µg/LNo recent samples✓ Public
2Eldred Sherwood LakeHancock3 ft89 µg/L31.3 µg/LNo recent samplesNot recorded
Lake GeorgeHancockNo recent samplesNo recent samplesNo recent samplesNo recent samplesNot recorded
Eagle LakeHancockNo recent samplesNo recent samplesNo recent samplesNo recent samplesNot recorded
East Twin LakeHancockNo recent samplesNo recent samplesNo recent samplesNo recent samplesNot recorded
West Twin LakeHancockNo recent samplesNo recent samplesNo recent samplesNo recent samples✓ 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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Source: the Iowa Department of Natural Resources. See data sources.