Safest Lakes to Swim In in Iowa
16 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 | 20 µg/L | 2.3 µg/L |
| 2 | Dale Maffitt Reservoir | Dallas | A | 9.8 ft | 20 µg/L | 2.1 µg/L |
| 3 | Blue Pit Lake | Cerro Gordo | A | 17.1 ft | 20 µg/L | 2.4 µg/L |
| 4 | Ada Hayden Heritage Park Lake | Story | A | 6.8 ft | 19 µg/L | 5.2 µg/L |
| 5 | Little Sioux Park Lake | Woodbury | A | 5.7 ft | 19 µg/L | 5.7 µg/L |
| 6 | Rudd Lake | Floyd | A | 8.1 ft | 14 µg/L | 4.5 µg/L |
| 7 | Slipbluff Lake | Decatur | A | 9 ft | 17.5 µg/L | 4.5 µg/L |
| 8 | Lacey Keosauqua Lake | Van Buren | A | 7.1 ft | 21.5 µg/L | 4.7 µg/L |
| 9 | Yenruogis Pond | Keokuk | A | 9.9 ft | 21 µg/L | 6.2 µg/L |
| 10 | Sand Lake | Marshall | A | 6.4 ft | 25 µg/L | 3.6 µg/L |
| 11 | Terra Park Lake | Polk | A | 11.5 ft | 20 µg/L | 4.7 µg/L |
| 12 | Arrowhead Lake | Sac | B | 5.6 ft | 26 µg/L | 7.1 µg/L |
| 13 | Mariposa Lake | Jasper | B | 5.1 ft | 31 µg/L | 8.9 µg/L |
| 14 | Mormon Trail Lake | Adair | B | 6.2 ft | 25 µg/L | 9.7 µg/L |
| 15 | Willow Lake | Harrison | B | 4.8 ft | 35 µg/L | 9.5 µg/L |
| 16 | Poll Miller Park Lake | Lee | B | 5.9 ft | 28 µg/L | 7.7 µg/L |
More Answers for Iowa
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