Safest Lakes to Swim In in Iowa
12 lakes in Iowa qualify as safest for swimming, all hold grade A or B and report chlorophyll-a (algae) under 10 µg/L. Always check local advisories on the day you swim.
Ranked List
| # | Lake | County | Grade | Clarity | Phosphorus | Algae |
|---|---|---|---|---|---|---|
| 1 | West Okoboji Lake | Dickinson | A | 15.7 ft | - | 2.6 µg/L |
| 2 | Blue Pit Lake | Cerro Gordo | A | 17.1 ft | - | 4 µg/L |
| 3 | Nine Eagles Lake | Decatur | A | 11 ft | - | 3.3 µg/L |
| 4 | Terra Park Lake | Polk | A | 11.5 ft | - | 4.7 µg/L |
| 5 | Dale Maffitt Reservoir | Dallas | B | 9.8 ft | - | 2.5 µg/L |
| 6 | Rudd Lake | Floyd | B | 8.1 ft | - | 4.5 µg/L |
| 7 | Slipbluff Lake | Decatur | B | 9 ft | - | 4.5 µg/L |
| 8 | Lacey Keosauqua Lake | Van Buren | B | 7.1 ft | - | 4.7 µg/L |
| 9 | Yenruogis Pond | Keokuk | B | 9.9 ft | - | 6.2 µg/L |
| 10 | Ada Hayden Heritage Park Lake | Story | B | 6.8 ft | - | 5.3 µg/L |
| 11 | Lambach Lake | Scott | B | 7.9 ft | - | 5.1 µg/L |
| 12 | Sand Lake | Marshall | B | 6.4 ft | - | 3.6 µg/L |