Linn County Lake Quality
Iowa, 4 lakes, measured by Iowa DNR
Linn County has 4 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. 2 of those lakes carry recent nutrient and algae readings. The county-level summary describes that subset, not every water body listed. Phosphorus and algae readings vary widely across Linn County; the per-lake pages below carry the numbers.
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. Pleasant Creek Lake has the lowest nutrient and algae readings in the county.
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Quick Answers for Linn County
Planning a trip? Check special fishing regulations for Pleasant Creek Lake — or check the official Iowa fishing regulations.
All Lakes in Linn County
4 lakes · 2 ranked on readings, 2 without enough sampling2 lakes ranked on readings · 2 without enough sampling, hidden
| # | Lake | Clarity | Phosphorus | Algae | Trophic | Access |
|---|---|---|---|---|---|---|
| 1 | Pleasant Creek LakeLinn | 3.6 ft | 38 µg/L | 26.5 µg/L | No recent samples | ✓ Public |
| 2 | Cedar LakeLinn | 0.9 ft | 256.5 µg/L | 125.4 µg/L | No recent samples | ✓ Public |
| Big Lewis LakeLinn | No recent samples | No recent samples | No recent samples | No recent samples | Not recorded | |
| Little Lewis LakeLinn | 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.