Iowa DNR
ADBNet

Water Quality Assessments

Impaired Waters List

2020 Impaired Waters Map DRAFT

Category 5
The State's Section 303(d) list of impaired waters. The waterbody is impaired and a total maximum daily load (TMDL) is needed.
Category 4
The waterbody is impaired but a TMDL is not required or a TMDL has already been completed. The waterbody is not included on the state’s section 303(d) list of impaired waters.