Assessment Comments
Assessment remains based on results of an IDNR fish kill investigation in September 2008.
Basis for Assessment
SUMMARY: The presumptive Class A1 (primary contact recreation) uses and Class A2 secondary contact recreation uses remain "not assessed" due to a lack of water quality information at this stream reach. The Class B(LW) aquatic life uses remain assessed (monitored) as "partially supported" due to a fish kill in September 2008. The fish consumption uses are "not assessed" due to lack of fish contaminant monitoring in this stream.
EXPLANATION: A fish kill occurred on this stream reach on September 11, 2008. The kill affected 1.9 miles of the South Branch of Fountain Spring Creek, Delaware County near Greeley. The kill was caused by high levels of ammonia due to manure runoff from an open feedlot. The kill affected almost exclusively trout. Fish carcass condition suggested that fish had been dead for 1-3 days. A high-quality trout fishery exists in Fountain Springs Creek and dead trout included recent “put-and-take” rainbow trout and feral brown trout up to 15 inches in length. Fountain Springs Creek annually supports about 14,500 fishing trips and is of significant importance to the rural community in northeast Delaware County. An estimated 55 fish were killed. The party responsible for the kill was identified, and restitution was sought.
According to IDNR’s assessment/listing methodology, the occurrence of a single pollutant-caused fish kill, or a fish kill of unknown origin, on a waterbody or waterbody reach during the most recent assessment period indicates a severe stress to the aquatic community and suggests that the aquatic life uses should be assessed as “impaired.” If a cause of the kill is identified, and the cause is either known, or suspected, to be a “pollutant,” the assessment type is considered “monitored” and the affected waterbody is a candidate for Section 303(d) listing. 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 will be placed in IR Category 4d (impaired but TMDL not required). IDNR feels that (1) TMDLs should not be required for kills caused by a one-time illegal or unauthorized release of manure or other toxic substance where enforcement actions were taken and (2) enforcement action is more appropriate, efficient, and effective for addressing a spill-related impairment than is the TMDL process. Thus, this assessment segment was placed in Category 4d of Iowa’s 2010 Integrated Report and remains in Category 4d of Iowa’s 2012 Integrated Report.
