Iowa DNR
Iowa DNR
ADBNet
Water Quality Assessments
Impaired Waters List

Bridge Creek IA 03-NSK-1898

mouth (T75N R11W Sec18 Keokuk Co.) to headwaters (T77N R12W Sec30 Keokuk Co.)

Assessment Cycle
2004
Result Period
2000 - 2002
Designations
Assessment Methodology
Assessment Type
Evaluated
Integrated Report
Category 1
Legacy ADBCode
IA 03-NSK-0034_0
Overall Use Support
Threatened
Aquatic Life Use Support
Documentation
Assessment Comments

Assessment based on 1999 Fisheries data: Fish IBI = 31 (fair).

Basis for Assessment

The assessment was based on data collected in 1999 as part of a DNR Fisheries stream sampling project: Manchester research station.   A series of biological metrics which reflect stream water quality and habitat integrity were calculated from the Fisheries sampling data.   The biological metrics are based on the numbers and types of 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).   The index ranks the biological integrity of a stream sampling reach on a rising scale from 0 (minimum) to 100 (maximum).   The 1999 evaluated Fish IBI was 31 (fair).   The overall use support was assessed (evaluated) as Fully Supporting/Threatened (=FS/T), based on a comparison of the F-IBI score with biological assessment criteria established for previous Section 305(b) reports.   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
1/1/1999 Biological Monitoring
Methods
315 Regional reference site approach
330 Fish surveys
Monitoring Levels
Biological 3
Habitat 0
Physical Chemistry 0
Toxic 0
Pathogen Indicators 0
Other Health Indicators 0
Other Aquatic Life Indicators 0
# of Bio Sites 1
BioIntegrity Fair