Polk County Lake Quality
Iowa, 11 lakes, measured by Iowa DNR
Polk County holds 11 monitored lakes. With a sample that small the county-level summary describes those specific waters, not necessarily every water body in the county. 8 of those lakes carry recent nutrient and algae readings. The county-level summary describes that subset, not every water body listed. Most monitored lakes in Polk County are productive, shallow basins; each lake page shows its own phosphorus and chlorophyll-a readings beside the EPA condition class.
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. Terra Park Lake has the lowest nutrient and algae readings in the county.
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Quick Answers for Polk County
Planning a trip? Check special fishing regulations for Terra Park Lake — or check the official Iowa fishing regulations.
All Lakes in Polk County
11 lakes · 8 ranked on readings, 3 without enough sampling8 lakes ranked on readings · 3 without enough sampling, hidden
| # | Lake | Clarity | Phosphorus | Algae | Trophic | Max Depth | Access |
|---|---|---|---|---|---|---|---|
| 1 | Terra Park LakePolk | 11.5 ft | 20 µg/L | 4.7 µg/L | No recent samples | No recent samples | ✓ Public |
| 2 | Lake PetockaPolk | 3.3 ft | 39.5 µg/L | 9.3 µg/L | No recent samples | No recent samples | Not recorded |
| 3 | Thomas Mitchell LakePolk | 3.3 ft | 87 µg/L | 13.2 µg/L | No recent samples | No recent samples | Not recorded |
| 4 | Easter LakePolk | 2.9 ft | 49.5 µg/L | 22.8 µg/L | No recent samples | No recent samples | ✓ Public |
| 5 | Big Creek LakePolk | 2.6 ft | 80 µg/L | 35.7 µg/L | No recent samples | No recent samples | ✓ Public |
| 6 | Grays LakePolk | 1.6 ft | 103 µg/L | 46.5 µg/L | No recent samples | No recent samples | ✓ Public |
| 7 | Blue Heron LakePolk | 2.2 ft | 78.5 µg/L | 57.9 µg/L | No recent samples | No recent samples | Not recorded |
| 8 | Fort des Moines Park PondPolk | 2.8 ft | 68 µg/L | 32.6 µg/L | No recent samples | No recent samples | Not recorded |
| Big Creek Beach LakePolk | No recent samples | No recent samples | No recent samples | No recent samples | No recent samples | Not recorded | |
| Brenton SloughPolk | No recent samples | No recent samples | No recent samples | No recent samples | No recent samples | Not recorded | |
| Saylorville LakePolk | No recent samples | No recent samples | No recent samples | No recent samples | 42.6 ft | ✓ 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.