Iowa DNR
Iowa DNR
ADBNet
Water Quality Assessments
Impaired Waters List

Des Moines River IA 04-LDM-1020

upper end of Red Rock Reservoir (W line S34 T77N R20W Marion Co.) to confluence with South R. in S12 T77N R22W Warren Co.

Assessment Cycle
1996
Result Period
1992 - 1994
Designations
Assessment Type
Monitored
Integrated Report
Category 0
Legacy ADBCode
IA 04-LDM-0040_1
Overall Use Support
Not supporting
Aquatic Life Use Support
Threatened
Fish Consumption
Threatened
Primary Contact Recreation
Not supporting
Documentation
Assessment Comments

Assessment is based on IDNR ambient monthly city monitoring dstr from Des Moines.

Basis for Assessment

At Hwy 46 had 14 of 16 non-flow affected samples viol Class A WQC for fecal coliforms; 14 of 18 samples at Runnels also in violation; thus, assess Class A as NS.   This is a more severe assessment than the PS in 1994.   Levels have declined from early 1980s but still generally > 200 orgs/100ml.   Of the 46 samples analyzed at each station for toxics, only had 1 of 8 samples > Class B WQC for copper, and had 6 of 9 samples in viol of Class B WQC for mercury (=67%).   Based on lack of source and on lack of HG problems in fish tissue, data for Hg and Cu are disregarded for 305(b) assessments.

Monitoring and Methods
Assessment Key Dates
Methods
420 Water column surveys (e.g. fecal coliform)
230 Fixed station physical/chemical (conventional plus toxic pollutants)
Monitoring Levels
Biological 0
Habitat 0
Physical Chemistry 3
Toxic 0
Pathogen Indicators 0
Other Health Indicators 0
Other Aquatic Life Indicators 0
# of Bio Sites 0
BioIntegrity N/A