Jefferson County Lake Quality
Iowa, 3 lakes, measured by Iowa DNR
Jefferson County has 3 monitored lakes — a thin enough sample that one or two stressed lakes can move the county average noticeably. Use the per-lake pages below for what actually matters. The 3 monitored lakes in Jefferson County carry whatever clarity, phosphorus, and chlorophyll-a readings Iowa DNR 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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Quick Answers for Jefferson County
Planning a trip? Check special fishing regulations for Reservoir Number Two — or check the official Iowa fishing regulations.
All Lakes in Jefferson County
3 lakes · 0 ranked on readings, 3 without enough sampling0 lakes ranked on readings · 3 without enough sampling, hidden
| # | Lake | Clarity | Phosphorus | Algae | Trophic | Access |
|---|---|---|---|---|---|---|
| Reservoir Number TwoJefferson | No recent samples | No recent samples | No recent samples | No recent samples | Not recorded | |
| Walton LakeJefferson | No recent samples | No recent samples | No recent samples | No recent samples | Not recorded | |
| Horse Shoe LakeJefferson | No recent samples | No recent samples | No recent samples | No recent samples | Not 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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Source: the Iowa Department of Natural Resources. See data sources.