Clear Creek IA 01-UIA-235
mouth (Allamakee Co.) to west line of S25 T99N R4W Allamakee Co.
- Cycle
- 2020
- Release Status
- Final
- Overall IR
- 3 - Insufficient data exist to determine whether any designated uses are met.
- Trend
- Unknown
- Created
- 8/21/2020 2:19:04 PM
- Updated
- 10/15/2020 9:57:26 AM
The Class BCW1 use was assessed as "partially supported" based on biological sampling data. All other designated uses were "not assessed".
Sources of
Data: Data Source Data Source ID Data Type Data Age Site ID Site Name Site Description Iowa DNR 6 BIO See Below 666 Clear Creek Lansing - CCr1 Presumptive Class A1 - No Data Presumptive Class A2 - No Data Class BCW1
- Biological Sampling: Benthic
Macroinvertebrates: BioNet Site ID Date Drainage Area (mi2) Ecoregion Major Drainage/Thermal BM Sample Gear CBI score CBI Class CBI BIT CBI Pass/ Fail 666 7/19/17 11 52b MS/CW Hess 54 NA 60 Fail Overall
Assessment: Community Assessment Type Assessment Result Support Level Earned IR Category Actual IR Category Reason Benthic
Macroinvertebrates Evaluated Fail (0/1) Partial 3bc 3bc Assessment
is evaluated because it was based on a single sample. Class BCW1 – Trout Natural Reproduction: In contrast to the benthic macroinvertebrate data, based on the January 2020 trout reproduction in Iowa streams summary prepared by the DNR Fisheries Bureau, the Class BCW1 coldwater aquatic life use of Clear Creek was assessed as "fully supported". According to the updated summary, this stream was placed in Category I: streams that exhibit consistent natural reproduction and maintain a wild population of one or more trout species without any stocking. Class BCW1 – Continuous Monitoring Data: The results of continuous dissolved oxygen (DO) and temperature monitoring in 2013 for the DNR/SHL coldwater stream sampling project also did not suggest impairment of Class BCW1 uses. The lowest DO concentration recorded in 71 days of continuous monitoring was 7.0 mg/L. The daily DO minimum concentration failed to meet the 24-hour DO criterion (5 mg/L) and the 16-hour DO criterion (7 mg/L) in 0 of 71 days each. The percentage exceeding (0%) was less than (passing) the 10% impairment threshold used to assess conventional water quality parameters. The associated statistical analysis confidence level was high (>90%). The maximum stream temperature recorded during the sensor deployment period was 20.9 degrees (C). The BCW1 temperature criterion of 20 (C) was exceeded in 5 of 71 days. The percentage exceeding (7%) was less than (passing) the 10% impairment threshold; however, the statistical analysis confidence level (< 90%) was not high. Based on these data, the BCW1 aquatic life use was assessed as fully supporting with respect to DO and temperature. The assessment type is “evaluated” because it is based on data collected from a single year within the current data assessment period. Class HH - No Data