Iowa DNR
Iowa DNR
ADBNet
Water Quality Assessments
Impaired Waters List

Mud Creek IA 06-LSR-6247

from mouth (T94N R41W Sec17) to headwaters (T94N R42W Sec5)

Cycle
2018
Release Status
Final
Overall IR
4 - Water is impaired or threatened and a TMDL has been completed or is not needed.
Trend
Unknown
Created
7/25/2019 1:53:21 PM
Updated
7/25/2019 1:55:09 PM
Use Support
Class A1
Recreation - Primary contact
Not Assessed
Class BWW1
Aquatic Life - Warm Water Type 1
Partially Supported
Support Level
Partially Supported
Impairment Code
4d - Pollutant-caused fish kill. No TMDL needed and administrative action taken against responsible party.
Cause Magnitude
Moderate
Status
Continuing
Source
Agriculture
Source Confidence
High
Cycle Added
2010
Impairment Rationale
Pollutant-caused fish kill
Data Source
Fish kill investigation: Iowa DNR
General Use
General Use water -
Not Assessed
Impairment Delistings
No delistings for this assessment cycle.
Documentation
Assessment Summary

The presumptive Class A1 (primary contact recreation) uses remain "not assessed" due to a lack of information upon which to base an assessment. The presumptive Class B(WW-1) aquatic life uses remain assessed as "partially supported" based on results of a fish kill investigation in July 2008.

Assessment Explanation

A fish kill occurred on this stream reach on July 22, 2008. The kill affected 1 mile of Mud Creek, O'Brien County, in LeMars. The kill was caused by leachate of dairy waste into a storm water ditch that discharges to Mud Creek. The spill caused severe oxygen depletion, which led to the fish kill. An estimated 270 fish were killed. The party responsible for the kill was identified, and restitution was sought.

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. 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). DNR 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 IR Category 4d.

Monitoring and Methods
Assessment Key Dates
7/22/2008
Fish Kill
Methods
120
Surveys of fish and game biologists/other professionals
140
Incidence of spills and/or fish kills
150
Monitoring data more than 5 years old