Bear Creek IA 03-SSK-959
from north line of S32 T85N R23W (Story Co.) to confluence with unnamed tributary in NE 1/4 S23 T86N R23W Hamilton Co.
Assessment Comments
1997 bioassessments (spp./fam.): dstr Roland WWTP, 12/4; upstr Roland WWTP, 11/4. 1997 Biocriteria: upstream/downstream Fish IBI= 25(poor)/35(fair), BM-IBI= 58(good)/44(fair). Fish kill in August 2001.
Basis for Assessment
The general aquatic life uses remain assessed as "partially supported" based on (1) results of biological monitoring in 1997 and (2) the occurrence of a fish kill in August 2001. EXPLANATION: Results of biological monitoring near the Roland wastewater treatment plant in 1997 suggested only "partial support" of the general aquatic life uses. These data are less than five years old and are thus useful for characterizing current water quality conditions. In addition, a fish kill occurred on this stream segment on August 27, 2001. The kill affected 0.3 miles of Bear Creek in Sections 24 and 25 of T86N, R23W, Hamilton County approximately four miles north of Roland. The kill was caused by release of manure from a swine production facility. An estimated 2,400 fish were killed. According to DNR's assessment methodology for Section 305(b) reporting, occurrence of a single pollution-caused fish kill during the most recent three-year period indicates "partial support" of the aquatic life uses. Thus, the general aquatic life uses of this stream were assessed as "partially supported."
Assessment Key Dates
| 8/27/2001 | Fishkill |
| 9/25/1997 | Biological Monitoring |
Methods
| 330 | Fish surveys |
| 380 | Quan. measurements of instream parms-- channel morphology-- floodplain-- 1-2 seasons-- by prof |
| 140 | Incidence of spills and/or fish kills |
| 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 | Use Support | Cause Magnitude | Sources | Source Magnitude |
|---|---|---|---|---|
| Nutrients | Overall Use Support | Moderate |
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| Nutrients | Aquatic Life Support | Moderate |
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| Organic enrichment/Low DO | Overall Use Support | Moderate |
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| Organic enrichment/Low DO | Aquatic Life Support | Moderate |
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| Other habitat alterations | Overall Use Support | Moderate |
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| Other habitat alterations | Aquatic Life Support | Moderate |
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| Unionized Ammonia | Aquatic Life Support | Moderate |
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