Assessment Comments
Assessment remains based on results of an IDNR investigation of fish kill in January 2001.
Basis for Assessment
[Note Prior to the 2008 Section 305(b) cycle, this stream segment was classified only for general uses. Due to changes in Iowa’s surface water classification that were approved by U.S. EPA in February 2008 (see http://www.iowadnr.gov/Portals/idnr/uploads/water/standards/files/swcdoc2.pdf), this segment is now presumptively designated for Class A1 (primary contact recreation) uses and for Class B(WW1) aquatic life uses. According to the Iowa Water Quality Standards, all perennial rivers and streams and all intermittent streams with perennial pools that are not specifically listed in the Iowa surface water classification are designated as Class A1 and Class B(WW1) waters. Thus, for the current assessment, perennial flow is presumed, and the available water quality monitoring data will be compared to the applicable Class A1 and Class B(WW1) water quality criteria.]
SUMMARY: The presumptive Class A1 (primary contact recreation) uses remain "not assessed" (IR 3a) due to the lack of information upon which to base an assessment. Previous assessments of support the presumptive Class B(WW1) aquatic life uses ("partially supporting") were based on a report of a fish kill in January 2001. Because Iowa DNR sought restitution from the responsible party for the value of the fish killed, the assessment of the aquatic life uses was placed in IR Category 4d. Due to the absence of kills subsequent to that kill, this assessment segment was considered “evaluated” and thus was moved from Category 4d (impaired but TMDL not required) to Category 3b (water in need of further investigation) of Iowa's 2006 Integrated Report where it remained through the 2012 Integrated Reporting cycle. Due to the age of the kill (greater than 10 years), this assessment is now considered "not assessed" (IR 3a).
EXPLANATION: A fish kill occurred on an unnamed tributary to Klondike Creek on January 10, 2001. The party responsible for the kill was identified and restitution was sought. The kill affected approximately 1 mile of an unnamed tributary to its confluence with Klondike Creek. An estimated 25 fish were killed. Although dead fish were observed in the unnamed tributary, they were not observed in Klondike Creek. The kill was caused by hog manure that reached the unnamed tributary. Temporary measures by the facility, such as building 3-4 dikes across the waterway, were implemented to further reduce the impact. Because the kill approached, but apparently did not reach, Klondike Creek, the general aquatic life uses of this stream segment were assessed as "fully supported / threatened" for the 2004 assessment/listing cycle.
According to DNR's assessment methodology for Section 305(b) reporting, occurrence of a single pollution-caused fish kill during an assessment period indicates "partial support" of the aquatic life uses. If, however, a consent order has been issued to the party responsible for the kill and monetary restitution has been sought for the fish killed, the affected waterbody should be placed in IR Category 4d (impaired but TMDL not required). Thus, this assessment segment was placed into Category 4d of Iowa's 2004 Integrated Report. According to IDNR's 2008 assessment/listing methodology, if no additional fish kills have occurred over at least a five-year period (i.e., no kills occurred in the period 2002-2006), the assessment of impairment should be considered “evaluated” (i.e., of lower confidence), and the waterbody segment should be moved from IR Category 4d to IR Category 3b (list of waters in need of further investigation). Thus, this segment was placed in Category 3b of Iowa's 2006 Integrated Report where it remained through the 2012 Integrated Reporting cycle. IDNR considers IR Category 4d waterbodies where no additional kills have been reported for a stream for over 10 years, as appropriate for IR Category 3a (not assessed). Thus, this assessment is moved to IR Category 3a for the 2014 cycle.
