DES MOINES - The Iowa Department of Natural Resources (DNR) is seeking public comment on the DNR’s intent to withdraw the Cedar River watershed nitrate total maximum daily load (TMDL). 

TMDLs include analyses and methods for improving water quality for water bodies on the state’s Clean Water Act 303d impaired waters list. In 2006, the DNR finalized a TMDL for nitrate in the Cedar River. The DNR created the Cedar River TMDL due to the nitrate impairment in the segment of the Cedar River which Cedar Rapids uses as a source for municipal drinking water.

The DNR has concluded that for the TMDL to be equitably and accurately implemented, substantial revisions would be necessary to address the design and implementation deficiencies. To ensure the equitable and accurate implementation of Iowa and federal law, the DNR proposes to withdraw the Cedar River TMDL. Because the previously impaired segment is no longer impaired for nitrate, it will not be placed back on the Iowa 303d impaired waters list. The DNR will continue to assess the nitrate levels in segment and will take appropriate action if it becomes impaired again for nitrate.

Written comments regarding the intent to withdraw the TMDL can be submitted until 4:30 p.m. on Monday, Nov. 7, 2022. Please send written comments via email to TMDLcomment@dnr.iowa.gov or by mail to DNR Water Quality Monitoring and Assessment Section, c/o TMDL Program, 502 East 9th St., Des Moines, IA 50319.

View the Public Notice of the Intent to Withdraw the Nitrate TMDL in the Cedar River Watershed on the DNR Water Quality Improvement Plans website.