
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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Quick Answers for Hancock County
Planning a trip? Check special fishing regulations for Crystal Lake Max Depth — or check the official Iowa fishing regulations.
All Lakes in Hancock County
6 lakes · 2 ranked on readings, 4 without enough sampling2 lakes ranked on readings · 4 without enough sampling, hidden
| # | Lake | Clarity | Phosphorus | Algae | Trophic | Access |
|---|---|---|---|---|---|---|
| 1 | Crystal Lake Max DepthHancock | 1.6 ft | 99 µg/L | 50.3 µg/L | No recent samples | ✓ Public |
| 2 | Eldred Sherwood LakeHancock | 3 ft | 89 µg/L | 31.3 µg/L | No recent samples | Not recorded |
| Lake GeorgeHancock | No recent samples | No recent samples | No recent samples | No recent samples | Not recorded | |
| Eagle LakeHancock | No recent samples | No recent samples | No recent samples | No recent samples | Not recorded | |
| East Twin LakeHancock | No recent samples | No recent samples | No recent samples | No recent samples | Not recorded | |
| West Twin LakeHancock | No recent samples | No recent samples | No recent samples | No 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.