Wally Taylor is the Legal Chair of the Sierra Club Iowa chapter.
The Iowa Department of Natural Resources recently issued its 2026 draft of impaired waters. This is a requirement of section 303(d) of the Clean Water Act. Every two years states must list the water segments that do not meet water quality standards. This year the DNR evaluated 1,100 water segments and has listed 723 of those segments as impaired. That means that two-thirds of the water segments evaluated do not meet water quality standards.
The impaired waters list containing those 723 water segments are supposed to have total maximum daily loads (TMDLs) prepared. A TMDL calculates how much pollution can be discharged into the water and still meet water quality standards. The TMDL also includes a Water Quality Improvement Plan that proposes the path to bringing the water into compliance with water quality standards.
The problem with the Iowa list is that there are numerous water segments that have been on the list since 2006 and 2008, with no TMDL having been prepared. Some of those waters on the list since 2006 and 2008 are designated as Outstanding Iowa Waters pursuant to Iowa’s antidegradation policy. These waters are entitled to extra protection.
Continue Reading...