2024 assessment for Soldier River

Soldier River IA 06-SOL-1674

from confluence with Jordan Cr. (S16 T82N R43W Monona Co.) confluence with East Soldier R. in S34 T84N R42W Monona Co.

2024
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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Overall IR

3 - Insufficient data exist to determine whether any designated uses are met.

Trend

Unknown

Created

12/22/2023 1:41:31 PM by

Updated

2/2/2024 9:25:23 AM by

Use Support

Class A1

Presumptive Use

Recreation - Primary contact

Not Assessed

Class BWW1

Aquatic Life - Warm Water Type 1

WINOFI

Biological: low aquatic macroinvertebrate IBI

Support Level

Further Investigation Needed

Impairment Code

3b-c - Use potentially biologically impaired based on calibrated IBI metrics.

Cause Magnitude

Moderate

303(d) Listing Status

New

Source

Unknown: Source Unknown

Source Confidence

Low

Cycle Added

2024

Impairment Rationale

Potential Impairment

Data Source

Biological monitoring: Iowa DNR WQMA

Class HH

Human Health -

Not Assessed

303(d) Delistings for this Cycle

No delistings for this assessment cycle.

Documentation

Assessment Summary

The Class BWW1 use was assessed as "WINOFI" 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	WQ	2021	417	Soldier River
Iowa DNR	6	BIO	See Below	417	Soldier River	Moorhead (REMAP #119)

Presumptive Class A1 - No Data

Class BWW1 - Biological Sampling:

Benthic Macroinvertebrates:

BioNet Site ID	Date	Drainage Area (mi2)	Ecoregion	Major Drainage/ Thermal	BM Sample Gear	BMIBI score	BMIBI Class	47m BMIBI BIT	BMIBI Pass/Fail
417	9/21/21	309.1	47m	MO/WW	Surber	34	Fair	54	Fail

Fish:

BioNet Site ID	Date	Drainage Area (mi2)	Ecoregion	Major Drainage/ Thermal	Riffle Stream?	FIBI score	FIBI Class	47m FIBI BIT	FIBI Pass/Fail
417	9/21/21	309.1	47m	MO/WW	NA	43	Fair	31	Pass

Class BWW1- Continuous DO Monitoring:

Site ID	Data Source ID	# Days Monitoring (2021)	DO Criteria Type	# 2021 violations / Violations needed for impairment	Violates Annual Significantly >10% Rule?	Assessment Type	Support Level
			24 hr	3/5	No
417	6	20	16 hr	2/5	No	Evaluated	Full

Overall:

Community	Assessment Type	Assessment Result	Support Level	IR Category	Reason
Benthic Macroinvertebrates	Evaluated	Fail (0/1)	WINOFI
Fish	Evaluated	Pass (1/1)	Full		Assessment was evaluated because the
Overall	Evaluated	Fail	WINOFI	3bc	assessment was based on a single sample.

Class HH – No Data

Monitoring and Methods

Assessment Key Dates

9/21/2021

Biological Monitoring

9/22/2021

Monitoring Start

10/11/2021

Monitoring End

Methods

200

Physical/Chemical Monitoring

315

Regional reference site approach

320

Benthic macroinvertebrate surveys

330

Fish surveys