Fish Kill Event - Dry Branch Creek
SE of Ossian
- Event ID
- 1064
- Date of Kill
- 9/18/2024
- Waterbody Type
- River/Stream
- Cause Origin
- Anthropogenic
- Cause
- Organic Material
- Mode
- Runoff
- Magnitude
- 3 (1001 - 5000 fish killed)
- Estimated Fish Killed
- 2,382
- Kill Length
- 2.60 miles
- Valuation
- $286.69
- Investigation Expenses
- $855.72
- County
- Winneshiek
- ESD Field Office
- FO 1
- Fisheries Office
- Decorah State Hatchery
- LongDD
- -91.80889
- LatDD
- 43.09430
- Created Date
- 10/3/2024 10:10:01 AM
- Last Update
- 10/3/2024 10:16:00 AM
Highlighted river segments indicate those impacted in part or whole by this fish kill event. It is not meant to represent the actual extent of the kill.
Location: Kill occurred in Dry Branch Creek in Section 32, and 33 of T96N, R8W, Winneshiek County and Section 4 and 9 of T95N, R8W, Fayette County. The length of stream assessed for fish kill was 2.6 miles (13,839 feet). Fish kill stream segment upstream coordinate = 43.09430, -91.80889 and downstream coordinate = 43.06483, -91.78702.
Cause of Kill: Silage leachate release from a dairy operation.
Methods: Fish kill assessment and valuation were determined using subsampling methodology from bridges for incompletely accessible sites as provided in procedures presented within American Fisheries Society Special Publication 35 and Iowa Administrative Code Chapter 571-113. The kill site was determined to be incompletely accessible given the length of kill over more than 2.6 miles of private agricultural property with hazards including fences, extremely limited water clarity, varied terrain and vegetation.
Comments: Stream conditions at time of assessment provided extremely limited water clarity with low flows. Water was an opaque grey/white color with filamentous strands of algae floating in water. Water cleared near lower end of kill area. Water smelled like soured milk. Algae covered rocks and submersed vegetation were coated with a white substance closer to source. Stream bed consisted of cobble/gravel substrate throughout. Live fish and tadpoles were observed within the impacted reach during assessment. Fish species identified in the kill included: Common Shiner, Creek Chub, Stoneroller, Brook Stickleback, Blacknose Dace, and Bluntnose Minnow. No fish was over 3 inches in length.
Fish Killed:
SPECIES NUMBER KILLED MONETARY VALUE
Minnows, shiners, chubs, and dace 2,346 $281.53
Stoneroller 36 $5.16
Totals 2,382 $286.69