Iowa DNR
Iowa DNR
ADBNet
Water Quality Assessments
Impaired Waters List

Mud Creek IA 06-BSR-1546

mouth (S26 T98N R46W Lyon Co.) to the IA-MN state line

Cycle
2020
Release Status
Final
Overall IR
5 - Water is impaired or threatened and a TMDL is needed.
Trend
Unknown
Created
6/19/2020 7:16:09 AM
Updated
10/15/2020 11:37:13 AM
Use Support
Class A1
Recreation - Primary contact
Partially Supported
Support Level
Partially Supported
Impairment Code
5a - Pollutant-caused impairment. TMDL needed.
Cause Magnitude
Moderate
Status
Continuing
Source
Unknown: Source Unknown
Source Confidence
Low
Cycle Added
2008
Impairment Rationale
Geometric mean criterion exceeded
Data Source
TMDL monitoring: Iowa DNR
TMDL Priority
Tier III
Class BWW2
Aquatic Life - Warm Water Type 2
Partially Supported
Support Level
Partially Supported
Impairment Code
5b - Biological impairment or pollutant-caused fish kill - unknown source. No administrative action.
Cause Magnitude
Moderate
Status
Continuing
Source
Unknown: Source Unknown
Source Confidence
Low
Cycle Added
2006
Impairment Rationale
Pollutant-caused fish kill
Data Source
Fish kill investigation: Iowa DNR
TMDL Priority
Tier IV
Support Level
Partially Supported
Impairment Code
5b-t - Biological - tentative
Cause Magnitude
Moderate
Status
Continuing
Source
Unknown: Source Unknown
Source Confidence
Low
Cycle Added
2006
Impairment Rationale
Low Biotic Index
Data Source
Biological monitoring: Iowa DNR WQMA
TMDL Priority
Tier IV
General Use
General Use water -
Not Assessed
Impairment Delistings
No delistings for this assessment cycle.
Documentation
Assessment Summary

The Class A1 use remains assessed as "partially supported" due to levels of indicator bacteria that violated state water quality criteria. The Class BWW2 use remains assessed as “partially supported” based on biological sampling data and also due to the occurrence of a fish kill.

Assessment Explanation

Sources of Data:

Data Source

Data Source ID

Data Type

Data Age

Site ID

Site Name

Site Description

Iowa DNR

6

WQ

CY 2002-2003

11600003

Mud Creek nr IA/MN Border (4)

Iowa DNR

6

WQ

CY 2002-2003

11600004

Mud Creek nr Doon (5)

Iowa DNR

6

BIO

See Below

399

Mud Creek

Lester – REMAP #136

Iowa DNR

6

BIO

See Below

504

Mud Creek

Alvord – REMAP #175

Class A1 - Indicator Bacteria:

Site ID

Data Source ID

# Samples / # Years

2002-2003 Geometric Mean

Annual Geometric Mean Violation

# Violations

% Violations

Significantly >10% Violations

Assessment Type

Support Level

11600003

6

18 / 2

328

Yes

11

61%

Yes

Evaluated

Partial

11600004

6

20 / 2

839

Yes

14

70%

Yes

Evaluated

Partial

Class BWW2 - Biological Sampling:

Benthic Macroinvertebrates:

BioNet Site ID

Date

Drainage Area (mi2)

Ecoregion

Major Drainage/ Thermal

BM Sample Gear

BMIBI score

BMIBI Class

47a BMIBI BIT

BMIBI Pass/ Fail

504

8/29/05

126

47a

MO/WW

Hess

26

Poor

54

Fail

399

7/21/04

80

47a

MO/WW

ArtSub

58

Good

54

Pass

Fish:

BioNet Site ID

Date

Drainage Area (mi2)

Ecoregion

Major Drainage/ Thermal

Riffle Stream?

FIBI score

FIBI Class

47a FIBI BIT

FIBI Pass/ Fail

504

8/29/05

126

47a

MO/WW

NA

13

Poor

43

Fail

399

7/21/04

80

47a

MO/WW

NA

20

Poor

43

Fail

Overall:

Community

Assessment Type

Assessment Result

Support Level

Earned IR Category

Actual IR Category

Reason

Benthic Macroinvertebrates

Evaluated

Fail (1/2)

Partial

Fish

Evaluated

Fail (0/2)

Not

Overall

Evaluated

Fail

Partial

3bc

5bt

Assessment is evaluated because it was based on samples not collected in the last five years.

Class BWW2 – Fish kill Assessment:

The Class BWW2 aquatic life use assessment based on the 2003 fish kill placed this segment in Category 5b. The fish kill was caused by a “pollutant” or was suspected to be caused by a “pollutant”; therefore, the Class BWW2 use was considered impaired. Because the source of the pollutant was not identified and/or the enforcement actions taken against the responsible party have not been resolved, the Class BWW2 use was placed in Category 5b. Due to uncertainty regarding the recovery of the aquatic life following the fish kill, any existing fish kill 5b impairment will remain in Category 5b until more recent sampling has shown recovery of the aquatic community or the responsible party has paid restitution.

More details about the 2003 fish kill can be found here:https://programs.iowadnr.gov/fishkill/Events/574

Monitoring and Methods
Assessment Key Dates
3/18/2002
Fixed Monitoring Start Date
12/16/2003
Fixed Monitoring End Date
9/10/2003
Fish Kill
7/21/2004
Biological Monitoring
8/29/2005
Biological Monitoring
Methods
140
Incidence of spills and/or fish kills
150
Monitoring data more than 5 years old
220
Non-fixed station physical/chemical monitoring (conventional pollutant only)
315
Regional reference site approach
320
Benthic macroinvertebrate surveys
330
Fish surveys
420
Indicator bacteria monitoring