Iowa DNR
Iowa DNR
ADBNet
Water Quality Assessments
Impaired Waters List

Turkey Creek IA 04-UDM-6543

from Big Creek Lake (T81N R25W Sec14 Polk Co.) to headwaters (T81N R25W Sec1 Polk Co.)

Cycle
2020
Release Status
Final
Overall IR
5 - Water is impaired or threatened and a TMDL is needed.
Trend
Unknown
Created
10/1/2020 1:49:00 PM
Updated
10/9/2020 1:18:27 PM
Use Support
Class A1
Recreation - Primary contact
Partially Supported
Support Level
Partially Supported
Impairment Code
5p - Impairment occurs on a waterbody with a presumptive A1 or B(WW1) use.
Cause Magnitude
Slight
Status
Continuing
Source
Unknown: Source Unknown
Source Confidence
Low
Cycle Added
2014
Impairment Rationale
Geometric mean criterion exceeded
Data Source
Special project/study: Iowa DNR
TMDL Priority
Tier III
Class BWW1
Aquatic Life - Warm Water Type 1
Not Assessed
General Use
General Use water -
Not Assessed
Impairment Delistings
No delistings for this assessment cycle.
Documentation
Assessment Summary

The presumptive Class A1 use remains assessed as "partially supported" due to levels of indicator bacteria (E. coli) that violated state water quality criteria. 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

WQ

CY 2011

13770006

Big Creek 319 (BCW11)


Presumptive Class A1 - Indicator Bacteria:

Site ID

Data Source ID

# Samples / # Years

2011 Geometric Mean

Annual Geometric Mean Violation

# Violations

% Violations

Significantly >10% Violations

Assessment Type

Support Level

13770006

6

7 / 1

324

Yes

4

57%

Yes

Evaluated

Partial


Presumptive Class BWW1 - No Data



Monitoring and Methods
Assessment Key Dates
3/28/2011
Non-fixed Monitoring Start Date
9/28/2011
Non-fixed Monitoring End Date
Methods
150
Monitoring data more than 5 years old
220
Non-fixed station physical/chemical monitoring (conventional pollutant only)
420
Indicator bacteria monitoring