Turkey River IA 01-TRK-154

from confluence with Bohemian Cr. (S11 T97N R10W Winneshiek Co.) to Vernon Springs (road crossing in S34 T99N R11W Howard Co.)

Open Data Collection Period Modal

For purposes of developing stream/river water quality assessments for integrated reporting, three years of water quality data are typically used for both conventional pollutant parameters (e.g., indicator bacteria) and the less frequently monitored toxic parameters (e.g., toxic metals). Since the 2004 IR cycle, DNR has used a three-year data gathering period for streams, rivers, and beaches. For most assessments, the use of three years of data increases the number of samples upon which the decision on use support is based and helps address the problem of weather-related year-to-year fluctuations in water quality.

Due to the lower sampling frequency in Iowa’s ambient lake, biological, fish kill, and fish tissue monitoring programs, five years of data are used for developing IR assessments and for identifying Section 303(d) listings.

Data Type	Data Timeframe
Beach Sampling Data	CY 2020 - 2022
Stream/River Water Quality Data	CY 2020 - 2022
Lake Water Quality Data	CY 2018 - 2022
Biological Sampling Data	CY 2018 - 2022*
Fish Kill Data	CY 2018 - 2022
Fish Tissue Sampling Data	CY 2018 - 2022
Continuous Dissolved Oxygen Sampling Data	CY 2018 - 2022
*Biological sites sampled in both 2017 and 2021 were also assessed.

Open Segment Map
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Cycle: 2024
Release Status: Final
Overall IR: 5 - Water is impaired or threatened and a TMDL is needed.
Trend: Unknown
Created: 11/1/2023 8:12:32 AM
Updated: 1/31/2024 9:36:05 AM

Use Support

Class A1

Recreation - Primary contact

Not Supported

Bacteria: Indicator Bacteria- E. coli

Support Level

Not Supported

Impairment Code

5a - Pollutant-caused impairment. TMDL needed.

Cause Magnitude

Slight

Status

Continuing

Source

Unknown: Source Unknown

Source Confidence

N/A

Cycle Added

2016

Impairment Rationale

Geometric mean criterion exceeded

Data Source

Watershed project monitoring

TMDL Priority

Tier III

Class BWW1

Aquatic Life - Warm Water Type 1

Fully Supported

Class HH

Human Health -

Not Assessed

Impairment Delistings

No delistings for this assessment cycle.

Documentation

Assessment Summary

The Class A1 use was assessed as "not supported” based on levels of indicator bacteria (E. coli) that violated state water quality criteria. The Class BWW1 use was assessed as "fully supported" based on water quality monitoring data and 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	WQ	CY 2012-2014	15450014	Turkey River @ 345 Street	TR80 SE of Cresco
Iowa DNR	6	BIO	See Below	1018	Turkey River	Below Vernon Springs Dam – TK005
Iowa DNR	6	BIO	See Below	1020	Turkey River	Above Kings Bridge– TK006

Class A1 - Indicator Bacteria:

Site ID	Data Source ID	# Samples / # Years	2012 Geometric Mean	2013 Geometric Mean	2014 Geometric Mean	Annual Geometric Mean Violation	# Violations	% Violations	Significantly >10% Violations	Assessment Type	Support Level
15450014	6	23 / 3	74	384	665	Yes	8	35%	Yes	Evaluated	Not

Class A1 - pH:

Site ID	Data Source ID	# Samples / # Years	Maximum Value	Mean Value	Median Value	# Violations	% Violations	Significantly >10% Violations	Assessment Type	Support Level
15450014	6	24/ 3	8.5	8.2	8.2	0	0%	No	Evaluated	Full

Class BWW1 - Binomial Parameters:

Site ID	Data Source ID	Parameter Name	# Samples / # Years	Maximum Value	Mean Value	Median Value	# Acute / Chronic Violations	% Acute/ Chronic Violations	Significantly >10% Violations	Assessment Type	Support Level
15450014	6	Ammonia	16 / 2	0.47	0.08	0.05	0 / 0	0% / 0%	No	Evaluated	Full
15450014	6	Chloride	16 / 2	33	31.2	32.5	0 / 0	0% / 0%	No	Evaluated	Full
15450014	6	Dissolved oxygen	24 / 3	12	8.96	9	NA / 0	NA / 0%	No	Evaluated	Full
15450014	6	pH	24 / 3	8.5	8.2	8.2	0 / NA	0% / NA	No	Evaluated	Full
15450014	6	Temperature	24 / 3	27.3	14.8	15.95	0 / 0	0% / 0%	No	Evaluated	Full

Class BWW1 - Biological Sampling:

Fish:

BioNet Site ID	Date	Drainage Area (mi2)	Ecoregion	Major Drainage/Thermal	Riffle Stream?	FIBI score	FIBI Class	47c FIBI BIT	FIBI Pass/ Fail
1020	7/24/18	87	47c	MS/WW	Und.	65	Good	44/65	Pass
1018	7/23/18	80	47c	MS/WW	Und.	78	Excellent	44/65	Pass
1020	8/4/16	87	47c	MS/WW	Und.	67	Good	44/65	Pass
1018	8/4/16	80	47c	MS/WW	Und.	77	Excellent	44/65	Pass

Overall Assessment:

Community	Assessment Type	Assessment Result	Support Level	IR Category	Reason
Fish	Monitored	Pass (6/6)	Full	1	Assessment was monitored because there were two or more samples collected in the previous five years.

Class HH - No Data

Monitoring and Methods

Assessment Key Dates

4/4/2012

Monitoring Start

11/5/2014

Monitoring End

8/4/2016

Biological Monitoring

7/23/2018

Biological Monitoring

7/24/2018

Biological Monitoring

Methods

150

Monitoring data more than 5 years old

200

Physical/Chemical Monitoring

315

Regional reference site approach

330

Fish surveys

420

Indicator bacteria monitoring