Iowa DNR
Iowa DNR
ADBNet
Water Quality Assessments
Impaired Waters List

Burr Oak Creek IA 02-CED-581

from County Road T-46 (W line S10 T98N R16W Mitchell Co.) to N line S5 T98 R16W Mitchell Co.

Cycle
2020
Release Status
Final
Overall IR
5 - Water is impaired or threatened and a TMDL is needed.
Trend
Unknown
Created
9/1/2020 8:06:27 AM
Updated
10/16/2020 9:37:56 AM
Use Support
Class A1
Recreation - Primary contact
Not Assessed
Class A2
Recreation - Secondary contact
Not Assessed
Class BCW1
Aquatic Life - Cold Water Type 1
Partially Supported
Support Level
Partially Supported
Impairment Code
5b-v - Biological - verified
Cause Magnitude
Slight
Status
Continuing
Source
Unknown: Source Unknown
Source Confidence
Low
Cycle Added
2016
Impairment Rationale
Low Biotic Index
Data Source
Biological monitoring: Iowa DNR WQMA
TMDL Priority
Tier IV
Class HH
Human Health -
Not Assessed
General Use
General Use water -
Not Assessed
Impairment Delistings
No delistings for this assessment cycle.
Documentation
Assessment Summary

The Class BCW1 use remains assessed as "partially supported" based on biological sampling data. All other designated uses were "not assessed".

Assessment Explanation

Data Sources:

Data Source

Data Source ID

Data Type

Data Age

Site ID

Site Name

Site Description

Iowa DNR

6

BIO

See Below

230

Burr Oak Creek

Osage - US


Presumptive Class A1 - No Data


Presumptive Class A2 - No Data


Class BCW1 - Biological Sampling:

Benthic Macroinvertebrates:

BioNet Site ID

Date

Drainage Area (mi2)

Ecoregion

Major Drainage/ Thermal

BM Sample Gear

CBI score

CBI Class

CBI BIT

CBI Pass/ Fail

28

8/16/13

21

47c

MS/CW

Hess

47

NA

60

Fail

28

8/2/11

21

47c

MS/CW

Hess

63

NA

60

Pass

28

8/16/10

21

47c

MS/CW

Hess

50

NA

60

Fail

Overall Assessment:

Community

Assessment Type

Assessment Result

Support Level

Earned IR Category

Actual IR Category

Reason

Benthic Macroinvertebrates

Evaluated

Fail (1/3)

Partial

3bc

5bv

Assessment is evaluated because samples used to complete the assessment were not collected in the last five years.


Class BCW1 – Trout Natural Reproduction:

Based on the January 2020 trout reproduction in Iowa streams summary prepared by the DNR Fisheries Bureau, the Class BCW1 coldwater aquatic life use of Burr Oak Creek was assessed as "fully supported". According to the updated summary, this stream was placed in Category I: streams that exhibit consistent natural reproduction and maintain a wild population of one or more trout species without any stocking.


Class HH - No Data


Monitoring and Methods
Assessment Key Dates
8/2/2011
Biological Monitoring
8/6/2013
Biological Monitoring
1/1/2020
Biological Monitoring
8/16/2010
Biological Monitoring
Methods
120
Surveys of fish and game biologists/other professionals
150
Monitoring data more than 5 years old
315
Regional reference site approach
320
Benthic macroinvertebrate surveys
330
Fish surveys