Skip to main content
LakeQuality

16 lakes in Iowa lead the swimming list on clear, low-nutrient water with chlorophyll-a (algae) under 10 µg/L. Always check local advisories on the day you swim.

Ranked List

#LakeCountyClarityPhosphorusAlgae
1West Okoboji LakeDickinson15.7 ft20 µg/L2.3 µg/L
2Dale Maffitt ReservoirDallas9.8 ft20 µg/L2.1 µg/L
3Blue Pit LakeCerro Gordo17.1 ft20 µg/L2.4 µg/L
4Ada Hayden Heritage Park LakeStory6.8 ft19 µg/L5.2 µg/L
5Little Sioux Park LakeWoodbury5.7 ft19 µg/L5.7 µg/L
6Rudd LakeFloyd8.1 ft14 µg/L4.5 µg/L
7Slipbluff LakeDecatur9 ft17.5 µg/L4.5 µg/L
8Lacey Keosauqua LakeVan Buren7.1 ft21.5 µg/L4.7 µg/L
9Yenruogis PondKeokuk9.9 ft21 µg/L6.2 µg/L
10Sand LakeMarshall6.4 ft25 µg/L3.6 µg/L
11Terra Park LakePolk11.5 ft20 µg/L4.7 µg/L
12Arrowhead LakeSac5.6 ft26 µg/L7.1 µg/L
13Mariposa LakeJasper5.1 ft31 µg/L8.9 µg/L
14Mormon Trail LakeAdair6.2 ft25 µg/L9.7 µg/L
15Willow LakeHarrison4.8 ft35 µg/L9.5 µg/L
16Poll Miller Park LakeLee5.9 ft28 µg/L7.7 µg/L

More Answers for Iowa

Get Iowa water-quality updates

New readings can change this ranking. Unsubscribe anytime.