Roberts Creek IA 01-TRK-1931
confluence with unnamed tributary in S8 T95N R6W Clayton Co. to headwaters (T96N R6W Sec32 SW SE Allamakee Co.)
- Cycle
- 2016
- Release Status
- Final
- Overall IR
- 3 - Insufficient data exist to determine whether any designated uses are met.
- Trend
- Unknown
- Created
- 4/20/2016 10:42:16 AM
- Updated
- 11/21/2016 2:30:04 PM
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. The presumptive Class B(WW1) aquatic life uses of this stream remain assessed (evaluated) as “partially supported” (IR 3b) due to a fish kill in August 2005. The kill was caused by hog manure. The party responsible for the kill was identified, and IDNR has sought and received restitution for the value of the fish killed and the costs incurred by IDNR during investigation of the kill. Because more than five years have elapsed since the most recent kill in this segment, this 4d impairment was moved to IR Category 3b in Iowa’s 2012 Integrated Report and remains in IR 3b for the current (2016) IR. This kill also affected a portion of Roberts Creek (waterbody IA 01-TRK-0360-3).
A fish kill occurred in this stream segment on or before August 1, 2005 and was caused by a release of hog manure from an over-full storage pit. According to the IDNR investigation, an outdoor storage pit lacked sufficient capacity to handle the amount of manure delivered to it from an indoor storage pit; thus, an overflow occurred. Approximately 2.25 miles of Roberts Creek were affected by the resulting kill. The kill began in an unnamed tributary to Roberts Creek (this waterbody IA: 01-TRK-0361-0) in Section 8 of T95N, R6W, Clayton County, and proceeded downstream through Section 9, 15, and 15 of T95N, R6W. An estimated 8,000 fish were killed. Based on IDNR records, the value of the fish killed was estimated at $4,893. Other than a notation that the kill affected “mostly non-game species", no detailed information on species killed is available. The party responsible for the kill was identified. IDNR sought and received restitution for the value of the fish killed and the costs incurred by IDNR during investigation of the kill.
According to the IDNR 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 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. IDNR considers IR 4d fish kill waters with no subsequent kills in at least the five years subsequent to the kill as appropriate for movement to IR categories 2b or 3b (i.e., Iowa’s list of waters in need of further investigation). Thus, this fish kill impairment was moved to IR Category 3b for the 2012 Integrated Report and remains in IR Category 3b.