Clear Creek IA 02-IOW-1937

Assessment Comments

Assessment is based on results of violations of narrative WQ criteria as documented by volunteer monitors.

Basis for Assessment

SUMMARY/EXPLANATION:  The general uses of this stream are assessed (monitored) as "not supported" due to impacts of poorly and/or untreated  wastewater discharged to the headwaters of this stream.   This assessment is based on results of the an IDNR/IOWATER “snapshot” monitoring event in September 2003 that showed presence of toilet paper, floating sewage material, and a strong sewage smell coming from a tile line that discharges to the uppermost reaches of Clear Creek (see IDNR Water Fact Sheet 2005-2:  Snapshot Events; see also Neely et al.   2003.   Old Man’s Creek and Clear Creek, east-central Iowa:  the role of volunteers in a snapshot sampling (available at http://wqm.igsb.uiowa.edu/iowater/SnapshotResults/Oldmans.pdf )).   Subsequent investigations by volunteer (IOWATER) monitors and by IDNR staff have demonstrated that these impact continue to occur.  

The water quality conditions documented by volunteer monitors and by IDNR staff potentially violate several of Iowa's narrative water quality standards designed to protect general uses of Iowa's surface waters (e.g., livestock and wildlife watering, aquatic life and non-contact recreation).   The following of Iowa's narrative water quality standards are potentially violated in this segment of Clear Creek:

--such waters shall be free from substances from point source dischargers that will settle to form sludge deposits;

--such waters shall be free from floating debris, oil, grease, scum and other materials from wastewater discharges or agricultural practices in amounts sufficient to create a nuisance;

--such waters shall be free from materials from wastewater discharges or agricultural practices producing objectionable color, odor, or other aesthetically objectionable conditions;

Based on the information received by IDNR on this stream, the general uses are assessed (monitored) as "not supported" due to water quality impacts from poorly-treated and untreated domestic sewage being discharged to Clear Creek.