Hickory Creek IA 01-YEL-441
mouth (NE 1/4 S23 T96N R5W Allamakee Co.) to south line of S28 T96N R5W Allamakee Co.
- Cycle
- 2020
- Release Status
- Final
- Overall IR
- 5 - Water is impaired or threatened and a TMDL is needed.
- Trend
- Unknown
- Created
- 10/5/2020 11:22:57 AM
- Updated
- 10/16/2020 7:09:16 AM
The presumptive Class A1 use remains assessed as “partially supported” due to levels of indicator bacteria (E. coli) that exceeded state water quality criteria. The Class BCW1 use remains assessed as "partially supported" based on results of water quality monitoring from 2004-2006 that show violations of Class BCW1 criteria for dissolved oxygen. All other designated uses are “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 category for the Class A1 recreational use was changed from 5p (impaired; TMDL needed) to 4a (impaired; TMDL approved). Because not all impairments identified for this assessment segment are covered by the TMDL (biological impairment due to low dissolved oxygen), this segment remains in Category 5 of Iowa's Integrated Report (impaired and TMDL required).
Sources
of Data: Data Source Data Source ID Data Type Data Age Site ID Site Name Site Description Iowa DNR 6 WQ CY 2008-2009 15030007 Hickory Creek at Hickory Creek Rd Presumptive
Class A1 - Indicator Bacteria: Historical 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 15030007 6 15 / 2 696 422 Yes 13 86% Yes Evaluated Partial Presumptive
Class A2 – No Data Class
BCW1 - Conventional Parameters: Historical Site ID Data Source ID Parameter Name # Samples / # Years Maximum Value Mean Value Median Value # Acute / Chronic Violations % Acute/ Chronic Violations Significantly >10% Violations Assessment Type Support Level 15030007 6 Ammonia 17 / 2 0.06 0.05 0.05 0 / 0 0% / 0% No Evaluated Full 15030007 6 Dissolved oxygen 9 / 1 12.8 11.8 11.9 NA / 0 NA / 0% No Evaluated Full 15030007 6 pH 9 / 1 8.5 8.5 8.5 0 / NA 0% / NA No Evaluated Full 15030007 6 Temperature 9 / 1 19.4 14.4 14.4 0 / 0 0% / 0% No Evaluated Full According
to the DNR IR methodology, the percentage of violations of the dissolved oxygen
criterion in this stream segment during the 2004-06 period was significantly
greater than 10%; therefore, the Class BCW1 uses of this segment were assessed
as impaired for the 2010 cycle. Based on DNR's assessment methodology, two
consecutive assessment/listing cycles without significantly greater than 10% of
the samples violating the standard are necessary to suggest de-listing of an impairment
due to low dissolved oxygen. Therefore, the impairment for dissolved oxygen has
remained for the subsequent assessment/listing cycles. Class
BCW1 – Trout Natural Reproduction: In
contrast to the WQ 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 Hickory 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