Saunders Branch IA 03-SKU-902

mouth (SW 1/4 S17 T71N R6W Henry Co.) to headwaters

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 8:12:52 AM
Updated: 1/19/2024 2:25:55 PM

Use Support

Class A1

Presumptive Use

Recreation - Primary contact

Fully Supported

Class BWW1

Presumptive Use

Aquatic Life - Warm Water Type 1

Not Supported

Toxic Inorganics: Ammonia

Support Level

Not Supported

Impairment Code

5b-t - Biological - tentative

Cause Magnitude

Slight

Status

Continuing

Source

Municipal Wastewater Treatment Plant

Source Confidence

Low

Cycle Added

2004

Impairment Rationale

Low Biotic Index

Data Source

Biological monitoring: Iowa DNR WQMA

TMDL Priority

Tier IV

Toxic Organics: Coal Tar

Support Level

Not Supported

Impairment Code

5b-t - Biological - tentative

Cause Magnitude

Slight

Status

Continuing

Source

Municipal Wastewater Treatment Plant

Source Confidence

Low

Cycle Added

2004

Impairment Rationale

Low Biotic Index

Data Source

Biological monitoring: Iowa DNR WQMA

TMDL Priority

Tier IV

Organic Enrichment: Low Dissolved Oxygen

Support Level

Not Supported

Impairment Code

5b-t - Biological - tentative

Cause Magnitude

Slight

Status

Continuing

Source

Municipal Wastewater Treatment Plant

Source Confidence

Low

Cycle Added

2004

Impairment Rationale

Low Biotic Index

Data Source

Biological monitoring: Iowa DNR WQMA

TMDL Priority

Tier IV

Impairment Delistings

No delistings for this assessment cycle.

Documentation

Assessment Summary

The presumptive Class A1 use was assessed as "fully supported" based on water quality monitoring data. The presumptive Class BWW1 use was assessed as "not supported" based on biological sampling data. For the 2000 IR cycle, DNR added three Class BWW1 impairments: ammonia, coal tar and low dissolved oxygen. There was follow-up monitoring in this segment for the 2024 IR cycle that showed full support for the dissolved oxygen and ammonia impairments. DNR will conduct follow-up biological sampling and additional water quality monitoring in this segment for the 2026 IR cycle.

Assessment Explanation

Data Sources:

Data Source	Data Source ID	Data Type	Data Age	Site ID	Site Name	Site Description
Iowa DNR	6	WQ	CY 2021-2022	14000352	Saunders Branch
Iowa DNR	6	BIO	See Below	144	Saunders Branch	DS – Saunders Park – Mt Pleasant MGP
Iowa DNR	6	BIO	See Below	145	Saunders Branch	ADJ – Mt Pleasant MGP
Iowa DNR	6	BIO	See Below	146	Saunders Branch	US – Mt Pleasant MGP
Iowa DNR	6	BIO	See Below	147	Saunders Branch	SE WWTP DS – Mt Pleasant

Presumptive Class A1 - Indicator Bacteria: No Data

Presumptive 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
14000352	6	11 / 2	7.37	7.99	7.75	0	3	NO	Mon	Full

Presumptive 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
14000352	6	Dissolved Oxygen	11 / 2	6.14	12.37	8.12	0	NA / NA	3	NO	Mon	Full
14000352	6	pH	11 / 2	7.37	7.99	7.75	0	NA / NA	3	NO	Mon	Full
14000352	6	Temperature	11 / 2	7.73	26	17.67	0	NA / NA	3	NO	Mon	Full

Presumptive 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
14000352	6	Ammonia	10 / 2	0.45	0.15	0.11	0 / 0	NO	Mon	Full

Presumptive Class BWW1 - Biological Sampling:

Fish:

BioNet Site ID	Date	Drainage Area (mi2)	Ecoregion	Major Drainage/Thermal	Riffle Stream?	FIBI score	FIBI Class	40a FIBI BIT	FIBI Pass/Fail
147	10/14/98	3	40a	MS/WW	NA	37	Fair	33	Pass
144	10/13/98	2	40a	MS/WW	NA	32	Fair	33	Fail
145	10/13/98	2	40a	MS/WW	NA	20	Poor	33	Fail
146	10/13/98	1	40a	MS/WW	NA	24	Poor	33	Fail

Overall:

Community	Assessment Type	Assessment Result	Support Level	IR Category	Reason
Fish	Evaluated	Fail (1/4)	Not		Assessment was evaluated because it used samples not collected in the last five years
Overall	Evaluated	Fail	Not	5bt	and the drainage areas of the sample sites were smaller than the calibrated range.

Monitoring and Methods

Assessment Key Dates

10/13/1998

Biological Monitoring

10/14/1998

Biological Monitoring

6/3/2021

Monitoring Start

10/17/2022

Monitoring End

Methods

150

Monitoring data more than 5 years old

200

Physical/Chemical Monitoring

315

Regional reference site approach

330

Fish surveys