Iowa DNR
Iowa DNR Fish Kill Database

Fish Kill Event - Unnamed Tributary to Rock Creek

SW of Osage

Event ID
1003
Date of Kill
9/1/2020
Waterbody Type
Lake
Cause Origin
Natural
Cause
Environmental
Mode
N/A
Magnitude
2 (101 - 1000 fish killed)
County
Mitchell
ESD Field Office
FO 2
Fisheries Office
Decorah State Hatchery
LongDD
-92.94515
LatDD
43.25841
Created Date
9/8/2020 9:07:56 AM
Last Update
9/8/2020 9:53:15 AM
For more information about this fish kill event, contact the Field Office or Fisheries Office listed above.
Impacted Assessment Segments
No segments listed
Lat/Long uses WGS84 datum
Onsite Comments

A fish kill of more than 100 fish was reported this morning southwest of Osage in Mitchell County. The kill had actually first been observed on Tuesday this week. The location was along 340th Street from approximately Dancer Avenue to Echo Avenue (1 mile) in an unnamed tributary of Rock Creek. The incident was investigated today and determined to be from natural causes. Low Dissolved Oxygen levels (1.0 ppm) were found at this stretch of stream, which also had low flows and decomposition of organic matter occurring. No other contaminants were found in the water or other potential sources identified. There were also live fish seen in the stream, however it was apparent some were still being impacted by the low oxygen levels. These conditions are likely to continue until flows increase. There were no impacts observed to the receiving water, Rock Creek.