Iowa DNR
ADBNet

Water Quality Assessments

Impaired Waters List

Volga River IA 01-VOL-296

confluence with Little Volga R. (S2 T92N R9W Fayette Co.) to confluence with unnamed tributary in SE 1/4 S24 T93N R10W Fayette Co.

Assessment Cycle
2002
Result Period
1998 - 2000
Designations
Assessment Methodology
Assessment Type
Monitored
Integrated Report
Category 0
Legacy ADBCode
IA 01-VOL-0020_3
Overall Use Support
Fully
Aquatic Life Use Support
Fully
Documentation
Assessment Comments

Assessment based on 2001 biocriteria data: Fish IBI= 78 (excellent), 81 (excellent), and BM-IBI= 80 (excellent), 73 (good).

Basis for Assessment

The assessment was based on data collected in 2001 as part of the DNR/UHL stream biocriteria project.   A series of biological metrics which reflect stream water quality and habitat integrity were calculated from the biocriteria sampling data.   The biological metrics are based on the numbers and types of benthic macroinvertebrate taxa and fish species that were collected in the stream sampling reach.   The biological metrics were combined to make a fish community index of biotic integrity (F-IBI) and a benthic macroinvertebrate index (BM-IBI).   The indexes rank the biological integrity of a stream sampling reach on a rising scale from 0 (minimum) to 100 (maximum).   Two samples were collected within this stream segment in 2001.  The Fish IBI scores were 78 (excellent) and 81 (excellent).  The BM-IBI scores were 80 (excellent) and 73 (good).  The aquatic life use support was assessed as fully supporting (=FS), 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
9/18/2001 Biological Monitoring
9/17/2001 Biological Monitoring
Methods
220 Non-fixed station physical/chemical monitoring (conventional pollutant only)
315 Regional reference site approach
320 Benthic macroinvertebrate surveys
330 Fish surveys
380 Quan. measurements of instream parms-- channel morphology-- floodplain-- 1-2 seasons-- by prof
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 Good