Iowa DNR
Iowa DNR
ADBNet
Water Quality Assessments
Impaired Waters List

Rock Creek IA 02-CED-586

from confluence with unnamed tributary (NW 1/4 SE 1/4 S17 T97N R17W Mitchell Co.) confluence with Goose Cr. in S35 T98N R18W Mitchell Co.

Assessment Cycle
2002
Result Period
1998 - 2000
Designations
Assessment Methodology
Assessment Type
Evaluated
Integrated Report
Category 0
Legacy ADBCode
IA 02-CED-0510_2
Overall Use Support
Partial
Aquatic Life Use Support
Partial
Fish Consumption
Not assessed
Documentation
Assessment Comments

Assessment is based on results on 1996 biocriteria sampling: 16 spp.; 5 fams; Fish IBI=54 (good); BM IBI=55 (fair).

Basis for Assessment

SUMMARY:  The Class B(WW) aquatic life uses remain assessed as "partially supported."  The assessment category, however, is changed from "monitored" to "evaluated."  Fish consumption uses remain "not assessed."  EXPLANATION:  Continue to use the assessment developed for the 2000 report (see above) that was based on results of the 1996 IDNR biocriteria assessment.   However, because these data are now considered too old (greater than five years) to accurately characterize current water quality conditions, the assessment category is changed from "monitored" (indicating an assessment with relatively high confidence) to "evaluated" (indicating an assessment with relatively low confidence).   Fish consumption uses remain "not assessed" due to the lack of fish contaminant monitoring in this stream segment.

Monitoring and Methods
Assessment Key Dates
8/15/1996 Biological Monitoring
Methods
320 Benthic macroinvertebrate 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
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 1
BioIntegrity Good