Iowa DNR
ADBNet

Water Quality Assessments

Impaired Waters List

East Nodaway River IA 05-NOD-1391

mouth (S6 T67N R36W Page Co.) to confluence with Long Branch Cr at S17-18 line T70N R35W Taylor Co.

Assessment Cycle
2002
Result Period
1998 - 2000
Designations
Assessment Methodology
Assessment Type
Monitored
Integrated Report
Category 0
Legacy ADBCode
IA 05-NOD-0030_1
Overall Use Support
Threatened
Aquatic Life Use Support
Threatened
Fish Consumption
Not assessed
Documentation
Assessment Comments

Assessment is based on results of IDNR ambient monthly monitoring in 2000 & 2001 and (2) IDNR/UHL biocriteria sampling in 1998 (Fish IBI= 30(fair), BM-IBI= 59(fair)).

Basis for Assessment

SUMMARY:  The Class B(WW) aquatic life uses remain assessed as "fully supported / threatened."  Fish consumption uses remain assessed "not assessed."  This assessment is based on (1) results of IDNR monthly ambient monitoring conducted during the 2000-2001 biennial period at the State Highway 2 bridge 2 miles east of Clarinda (station 10730002 (formerly station 780809)) and (2) results of IDNR/UHL biocriteria monitoring in 1998.   EXPLANATION:  Monitoring at the IDNR station east of Clarinda showed no violations of Class B(WW) water quality criteria during the 2000-2001 biennial period for dissolved oxygen (minimum value = 7.7 mg/l), pH (range = 7.4 to 8.5 units), or ammonia-nitrogen (maximum value = 0.90) in the 24 samples analyzed during the 2000-2001 period.   In addition, levels of toxic metals in the four samples analyzed, and levels of pesticides in the six samples analyzed, were all below the analytical level of detection.   These results suggest "full support" of the Class B(WW) aquatic life uses.   Results of the IDNR biocriteria monitoring in 1998, however, suggest that the Class B(WW) uses are "fully supported / threatened" (see assessment for the 2000 report above).   Fish consumption uses remain "not assessed" due to the lack of recent fish tissue monitoring in this river reach.

Monitoring and Methods
Assessment Key Dates
9/4/2001 Fixed Monitoring End Date
10/4/1999 Fixed Monitoring Start Date
10/20/1998 Biological Monitoring
Methods
330 Fish surveys
380 Quan. measurements of instream parms-- channel morphology-- floodplain-- 1-2 seasons-- by prof
220 Non-fixed station physical/chemical monitoring (conventional pollutant only)
230 Fixed station physical/chemical (conventional plus toxic pollutants)
315 Regional reference site approach
320 Benthic macroinvertebrate surveys
Monitoring Levels
Biological 4
Habitat 4
Physical Chemistry 3
Toxic 0
Pathogen Indicators 0
Other Health Indicators 0
Other Aquatic Life Indicators 0
# of Bio Sites 1
BioIntegrity Fair
Causes and Sources of Impairment
Causes Use Support Cause Magnitude Sources Source Magnitude
Other habitat alterations Overall Use Support Not Impairing
  • Agriculture
  • Bank or Shoreline Modification/Destabilization
  • Channelization
  • Habitat Modification (other than Hydromodification)
  • Hydromodification
  • Not Impairing
  • Not Impairing
  • Not Impairing
  • Not Impairing
  • Not Impairing
Other habitat alterations Aquatic Life Support Not Impairing
  • Agriculture
  • Bank or Shoreline Modification/Destabilization
  • Channelization
  • Habitat Modification (other than Hydromodification)
  • Hydromodification
  • Not Impairing
  • Not Impairing
  • Not Impairing
  • Not Impairing
  • Not Impairing
Siltation Overall Use Support Not Impairing
  • Agriculture
  • Bank or Shoreline Modification/Destabilization
  • Channelization
  • Habitat Modification (other than Hydromodification)
  • Hydromodification
  • Not Impairing
  • Not Impairing
  • Not Impairing
  • Not Impairing
  • Not Impairing
Siltation Aquatic Life Support Not Impairing
  • Agriculture
  • Bank or Shoreline Modification/Destabilization
  • Channelization
  • Habitat Modification (other than Hydromodification)
  • Hydromodification
  • Not Impairing
  • Not Impairing
  • Not Impairing
  • Not Impairing
  • Not Impairing