Iowa DNR
Iowa DNR
ADBNet
Water Quality Assessments
Impaired Waters List

Maple River IA 06-LSR-1586

from confluence with Silver Cr. (S13 T88N R40W Ida Co.) to confluence with Maple Cr. in S5 T91N R39W Cherokee Co.

Assessment Cycle
2002
Result Period
1998 - 2000
Designations
Assessment Methodology
Assessment Type
Monitored
Integrated Report
Category 0
Legacy ADBCode
IA 06-LSR-0080_2
Overall Use Support
Threatened
Aquatic Life Use Support
Threatened
Documentation
Assessment Comments

1997 Biocriteria: Fish IBI=44 (fair),35 (fair); BM-IBI = 63 (good), 71 (good).

Basis for Assessment

The assessment was based on the 1997 biological sampling data (see 2000 assessment comments), and the aquatic life use support continued to be assessed as fully supporting / threatened (=FST) based on a comparison of the F-IBI and BM-IBI scores with biological assessment criteria established specifically for the 2002 Section 305(b) report.  The biological assessment criteria were determined from a statistical analysis of data collected at stream ecoregion reference sites from 1994-2001.

Monitoring and Methods
Assessment Key Dates
8/20/1997 Fixed Monitoring Start Date
8/20/1997 Fixed Monitoring End Date
8/20/1997 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)
315 Regional reference site approach
320 Benthic macroinvertebrate surveys
Monitoring Levels
Biological 4
Habitat 4
Physical Chemistry 1
Toxic 0
Pathogen Indicators 0
Other Health Indicators 0
Other Aquatic Life Indicators 0
# of Bio Sites 2
BioIntegrity Fair
Causes and Sources of Impairment
Causes Use Support Cause Magnitude Sources Source Magnitude
Other habitat alterations Overall Use Support Not Impairing
  • Agriculture
  • Channelization
  • Grazing related Sources
  • Hydromodification
  • Pasture grazing - Riparian
  • Not Impairing
  • Not Impairing
  • Not Impairing
  • Not Impairing
  • Not Impairing
Other habitat alterations Aquatic Life Support Not Impairing
  • Agriculture
  • Channelization
  • Grazing related Sources
  • Hydromodification
  • Pasture grazing - Riparian
  • Not Impairing
  • Not Impairing
  • Not Impairing
  • Not Impairing
  • Not Impairing