ADBNet

The most recent fish kill occurred on or before September 3, 2014, Near Garnavillo in Sections 4 and 9 of Clayton Township and in Section 16 of Garnavillo Township. The kill was attributed animal waste from a dairy operation. As estimated 36,350 fish were killed over approximately 5 miles of stream. According to the Iowa DNR fish kill investigation report, land-applied dairy confinement manure was applied too close to a waterway (Buck Creek). The value of the fish killed was estimated at $26,023.35, and the cost of the Iowa DNR investigation of the kill was $1,145.51. The party responsible for the kill was identified, and Iowa DNR sought and received partial restitution for the value of the fish killed and costs of the fish kill investigation. Based on this information, the Class B(WW2) aquatic life uses are assessed as “partially supporting” (IR 4d).

According to DNR’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. Fish kills attributed to a pollutant, but where a source of the pollutant was not identified and/or where enforcement actions were not taken against the responsible party, will be placed into Integrated Report subcategory 5b. The intent of placing these waterbodies into Category 5 is not to necessarily require a TMDL but to keep the impairment highlighted due to the potential for similar future kills from the unaddressed causes and/or sources.

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). Iowa DNR sought and received restitution for the value of the fish killed and the cost of the fish kill investigation. Thus, this assessment segment is placed in Category 4d of Iowa’s 2016 Integrated Report.

A previous fish kill occurred on or before June 8, 2009 and affected an unknown, but small number of fish. While the number of fish killed was small, the value of the fish was high, as many trout were killed. The kill occurred along a 4.5 mile stretch of Buck Creek one mile NNW of Garnavillo. The cause of the kill was suspected to be of human origin, as there was a recent pesticide spill to the stream and the potential from runoff from an open cattle feed lot. Updated information suggested that the kill was related to runoff from the open cattle feed lot. DNR sought and received restitution for this kill.