Upper Iowa River IA 01-UIA-237

from Lane's Bridge (NW 1/4 S31 T100N R4W Allamakee Co.) to confluence with Canoe Cr. in S25 T99N R7W Winneshiek 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 8:12:24 AM
Updated: 1/12/2024 2:59:37 PM

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

2004

Impairment Rationale

Geometric mean criterion exceeded

Data Source

Ambient monitoring: Iowa DNR-rivers

TMDL Priority

Tier III

Class BWW1

Aquatic Life - Warm Water Type 1

Fully Supported

Class HH

Human Health -

Not Supported

Fish Consumption Advisory: Mercury

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

2006

Impairment Rationale

Fish consumption advisory in effect: no more than 1 meal/week

Data Source

Fish contaminant monitoring: Iowa DNR

TMDL Priority

Tier IV

Impairment Delistings

No delistings for this assessment cycle.

Documentation

Assessment Summary

The Class A1 use was assessed as “not supported” due to levels of indicator bacteria (E. coli) that exceeded state water quality criteria. The Class BWW1 use was assessed as "fully supported" based on biological sampling data, water quality monitoring data, and on continuous dissolved oxygen monitoring data. The Class HH use was assessed as “not supported” based on fish tissue sampling data and on the existence of a historical fish consumption advisory for this segment of the Upper Iowa River.

Assessment Explanation

Data Sources:

Data Source	Data Source ID	Data Type	Data Age	Site ID	Site Name	Site Description
Iowa DNR	6	WQ	CY 2020-2022	10030001	Upper Iowa River near Dorchester
Iowa DNR	6	BIO	See Below	288	Upper Iowa River	Dorchester
Iowa DNR	6	FT	See Below	1363	Upper Iowa River	Wild Landing

Class A1 - Indicator Bacteria:

Site ID

Data Source ID

# Samples per Year (2020/ 2021/2022)

2020 Geometric Mean

2021 Geometric Mean

2022 Geometric Mean

Violates Annual Geometric Mean?

# 2020 SSM violations / SSM Violations needed for impairment

# 2021 SSM violations / SSM Violations needed for impairment

# 2022 SSM violations / SSM Violations needed for impairment

Violates Annual SSM Significantly >10% Rule?

Assessment Type

Support Level

10030001

8/8/8

115

146

144

YES

3 / 3

YES

Mon

Not

Class A1 – pH:

Site ID	Data Source ID	# Samples / # Years	Minimum Value	Maximum Value	Mean Value	# Violations	Violations needed for impairment	Violates Significantly >10% Rule?	Assessment Type	Support Level
10030001	6	36 / 3	8.1	8.4	8.2	0	7	NO	Mon	Full

Class BWW1 - Binomial Parameters:

Site ID	Data Source ID	Parameter Name	# Samples / # Years	Minimum Value	Maximum Value	Mean Value	# Violations	# Acute / Chronic Violations	Violations needed for impairment	Violates Significantly >10% Rule?	Assessment Type	Support Level
10030001	6	Chloride	36 / 3	12	19	15	NA	0 / 0	7	NO	Mon	Full
10030001	6	Dissolved Oxygen	36 / 3	7.6	14.6	11	0	NA / NA	7	NO	Mon	Full
10030001	6	pH	36 / 3	8.1	8.4	8.2	0	NA / NA	7	NO	Mon	Full
10030001	6	Sulfate	36 / 3	11	20	16	0	NA / NA	7	NO	Mon	Full
10030001	6	Temperature	36 / 3	0.1	23.8	10.9	0	NA / NA	7	NO	Mon	Full

Class BWW1 - Toxic Parameters:

Site ID	Data Source ID	Parameter Name	# Samples / # Years	Maximum Value	Mean Value	Median Value	# Acute / Chronic Violations	>1 Acute / Chronic Violation	Assessment Type	Support Level
10030001	6	Ammonia	36 / 3	0.47	0.04	0.02	0 / 0	NO	Mon	Full
10030001	6	Cadmium	20 / 3	0.5	0.5	0.5	0 / 0	NO	Mon	Full
10030001	6	Chromium	20 / 3	9	1.17	0.7	0 / 0	NO	Mon	Full
10030001	6	Lead	20 / 3	5.5	1.1	1	0 / 0	NO	Mon	Full
10030001	6	Nickel	20 / 3	6.1	1.2	0.8	0 / 0	NO	Mon	Full
10030001	6	Selenium	18 / 2	1	0.6	0.5	0 / 0	NO	Mon	Full
10030001	6	Silver	20 / 3	1	0.902	1	0 / 0	NO	Mon	Full
10030001	6	Zinc	20 / 3	16	1.5	0.5	0 / 0	NO	Mon	Full

Class BWW1 - Biological Sampling:

Benthic Macroinvertebrates:

Site ID	Date	Drainage Area (mi2)	Ecoregion	Major Drainage	BM Sample Gear	BMIBI score	BMIBI Class	52b BMIBI BIT	BMIBI Pass/Fail
483	10/12/21	896.9	52b	MS	Hess	77	Excellent	61	Pass
288	8/18/20	767.9	52b	MS	Hess	75	Excellent	61	Pass

Fish:

BioNet Site ID	Date	Drainage Area (mi2)	Ecoregion	Major Drainage/Thermal	Riffle Stream?	FIBI score	FIBI Class	52b FIBI BIT	FIBI Pass/Fail
483	10/12/21	896.9	52b	MS/WW	NA	78	Good	52	Pass

Overall:

Community	Assessment Type	Assessment Result	Support Level	IR Category	Reason
Benthic Macroinvertebrates	Evaluated	Pass (2/2)	Full
Fish	Evaluated	Pass (1/1)	Full		Assessment was evaluated because the drainage areas of the sites
Overall	Evaluated	Pass	Full	1	used for the assessment were greater than the calibrated range.

Class BWW1 - Continuous DO Monitoring:

Site ID	Data Source ID	# Days Monitoring (2016)	DO Criteria Type	# 2016 violations / Violations needed for impairment	Violates Annual Significantly >10% Rule?	Assessment Type	Support Level
			24 hr	0/6	No
288	6	29	16 hr	0/6	No	Evaluated	Full

Class HH - Fish Tissue Sampling:

Site ID	Biopart	Year	Species	# in sample / # of samples	Avg Length (cm)	(Avg) Hg (ppm)	Chlordane (ppm)	Sum PCBs (ppm)
1363	tissue plug	2021	northern pike	1	52.3	0.162
1363	tissue plug	2021	smallmouth bass	6	32.2	0.327
1363	tissue plug	2021	shorthead redhorse	10	41.7	0.217
1363	tissue plug	2020	northern pike	9	61.3	0.299
1363	tissue plug	2020	smallmouth bass	4	30.8	0.384
1363	tissue plug	2020	walleye	10	53.4	0.872
Support Level	Not	A historic one meal/week mercury consumption advisory for any fish exists on this segment. Based on IR Methodology, the Class HH (fish consumption) use was assessed as “not supported.”

Class HH-F - Toxic Parameters:

Site ID	Data Source ID	Parameter Name	# Samples / # Years	Maximum Value	Mean Value	Median Value	Number of Non - Detects	Mean Value > Criterion or MCL	Assessment Type	Support Level
10030001	6	Selenium	18 / 2	1	0.6	0.5	13	NO	Mon	Full

Monitoring and Methods

Assessment Key Dates

4/15/2020

Fish Tissue Monitoring

1/7/2020

Monitoring Start

12/1/2022

Monitoring End

8/18/2020

Fish Tissue Monitoring

8/18/2020

Biological Monitoring

7/7/2020

Fish Tissue Monitoring

7/31/2020

Fish Tissue Monitoring

4/7/2021

Fish Tissue Monitoring

10/12/2021

Biological Monitoring

Methods

200

Physical/Chemical Monitoring

260

Fish tissue analysis

315

Regional reference site approach

320

Benthic macroinvertebrate surveys

330

Fish surveys

420

Indicator bacteria monitoring