Bear Creek IA 01-YEL-440
Alternate name(s) for this segment: Unnamed Creek (aka Bear Cr.)
mouth (S13 T96N R5W Allamakee Co.) to north line of S12 T96N R5W Allamakee Co.
| Cycle Added | Class | Cause | Data Source | Rationale |
|---|---|---|---|---|
| 2006 | Class BCW1 | Organic Enrichment: Low Dissolved Oxygen | Ambient monitoring: Iowa DNR-rivers | New data: WQ improvement (chemical / physical / bacterial) |
The presumptive Class A1 use and Class A2 use remain assessed as “not supported” due to levels of indicator bacteria (E. coli) that exceeded state water quality criteria. The Class BCW1 use was assessed as "fully supported" based on water quality monitoring and on the trout reproduction in Iowa streams summary prepared by the DNR Fisheries Bureau. All other designated uses were “not assessed.” Note: A TMDL for the bacterial impairment for streams in the Yellow River basin was prepared by Iowa DNR in 2012 and was approved by U.S. EPA in February 2013. Due to completion of the TMDL, the Integrated Report categories for the presumptive Class A1 and Class A2 recreational uses were changed from 5p (impaired; TMDL needed) to 4a (impaired; TMDL approved).
Data Sources: Data Source Data Source ID Data Type Data Age Site ID Site
Name Site
Description Iowa DNR 6 WQ CY 2008-2009, CY 2021-2022 15030006 Bear
Creek nr Co. Rd. X26
Site ID Data Source ID # Samples / # Years 2008 Geometric Mean 2009 Geometric Mean Annual Geometric Mean Violation # Violations % Violations Significantly >10% Violations Assessment Type Support Level 15030006 6 26 / 2 218 874 Yes 15 58% Yes Evaluated Not Site ID Data Source ID # Samples / # Years 2008 Geometric Mean 2009 Geometric Mean Annual Geometric Mean Violation # Violations % Violations Significantly >10% Violations Assessment Type Support Level 15030006 6 26 / 2 218 874 Yes 10 38% Yes Evaluated Not Site ID Data Source ID # Samples / # Years Minimum Value Maximum Value Mean Value # Violations Violations needed for impairment Violates Significantly >10% Rule? Assessment Type Support Level 15030006 6 10 / 2 7.31 7.94 7.68 0 3 NO Mon Full Site ID Data Source ID Parameter Name # Samples / # Years Minimum Value Maximum Value Mean Value # Violations # Acute / Chronic Violations Violations needed for impairment Violates Significantly >10% Rule? Assessment Type Support Level 15030006 6 Dissolved Oxygen 10 / 2 7.87 12.24 9.39 0 NA / NA 3 NO Mon Full 15030006 6 pH 10 / 2 7.31 7.94 7.68 0 NA / NA 3 NO Mon Full 15030006 6 Temperature 10 / 2 7.43 15.12 12.68 0 NA / NA 3 NO Mon Full Based on the January 2024 summary of trout reproduction in Iowa streams
prepared by the DNR Fisheries Bureau, the Class BCW1 coldwater aquatic life use
of Bear 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 HH - No Data
Presumptive Class A1 - Indicator Bacteria: 2008-2009
Class A2 - Indicator Bacteria: 2008-2009
Presumptive Class A1 and Class A2 - pH: 2021-2022
Class BCW1 - Binomial Parameters: 2021-2022
Class BCW1 – Trout Natural Reproduction: