Upper Iowa River IA 01-UIA-244

river mile 86 (NE 1/4 S12 T100N R11W Howard Co.) to confluence with unnamed tributary in NE 1/4 S21 T100N R12W 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 8:12:45 AM
Updated: 2/6/2024 11:28:37 AM

Use Support

Class A1

Presumptive Use

Recreation - Primary contact

Not Assessed

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

Moderate

Status

Continuing

Source

Unknown: Source Unknown

Source Confidence

N/A

Cycle Added

2022

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 BWW1 use was assessed as "fully supported" based on biological sampling data and continuous dissolved oxygen monitoring. The Class HH (fish consumption) use was assessed as "not supported" because a one meal/week mercury consumption advisory for any fish exists on this segment. 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/WQ	See Below	330	Upper Iowa River	Florenceville – REMAP #32

Presumptive Class A1 – No Data

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
330	8/19/20	221	52b	MS	Hess	76	Excellent	61	Pass

Fish:

Site ID	Date	Drainage Area (mi2)	Ecoregion	Major Drainage	Riffle Stream?	FIBI score	FIBI Class	52b FIBI BIT	FIBI Pass/Fail
330	8/19/20	221	52b	MS	NA	85	Excellent	52	Pass

Overall:

Community	Assessment Type	Assessment Result	Support Level	IR Category	Reason
Benthic Macroinvertebrates	Evaluated	Pass (1/1)	Full
Fish	Evaluated	Pass (1/1)	Full	1
Overall	Evaluated	Pass	Full		Assessment was evaluated because it was based on a single sample.

Class BWW1 - Continuous DO Monitoring:

Site ID	Data Source ID	# Days Monitoring (2019/2020)	DO Criteria Type	# 2019 violations/Violations needed for impairment	# 2020 violations/Violations needed for impairment	Violates Annual Significantly >10% Rule?	Assessment Type	Support Level
			24 hr	0/3	0/16	No
330	6	10/16	16 hr	0/3	0/16	No	Evaluated	Full

Class HH - Fish Tissue Sampling:

Support Level

Not

A 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.”

Monitoring and Methods

Assessment Key Dates

8/19/2020

Monitoring End

8/3/2020

Monitoring Start

8/19/2020

Biological Monitoring

9/3/2019

Monitoring Start

9/27/2019

Monitoring End

Methods

200

Physical/Chemical Monitoring

260

Fish tissue analysis

315

Regional reference site approach

320

Benthic macroinvertebrate surveys

330

Fish surveys

380

Quantitative physical habitat assessment