Mississippi River IA 01-NEM-61

from Iowa R. (Louisa Co.) to Lock & Dam 15 at Davenport Scott 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 2018 - 2020
Stream/River Water Quality Data	CY 2018 - 2020
Lake Water Quality Data	CY 2016 - 2020
Biological Sampling Data	CY 2016 - 2020*
Fish Kill Data	CY 2016 - 2020
Fish Tissue Sampling Data	CY 2016 - 2020
Continuous Dissolved Oxygen Sampling Data	CY 2016 - 2020
*Biological sites sampled in both 2015 and 2019 were also assessed.

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Cycle: 2022
Release Status: Final
Overall IR: 5 - Water is impaired or threatened and a TMDL is needed.
Trend: Unknown
Created: 12/29/2021 12:04:05 PM
Updated: 1/12/2022 11:00:44 AM

Use Support

Class A1

Recreation - Primary contact

Not Supported

Bacteria: Indicator Bacteria- fecal coliform

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

2016

Impairment Rationale

Listing by adjacent state

Data Source

Ambient monitoring: adjacent state

TMDL Priority

Tier IV

Class BWW1

Aquatic Life - Warm Water Type 1

Not Supported

Fish Kill: Due To Natural Causes

Support Level

Further Investigation Needed

Impairment Code

3b - Use potentially impaired based on an evaluated assessment.

Cause Magnitude

Slight

Status

Continuing

Source

Natural

Source Confidence

Moderate

Cycle Added

2016

Impairment Rationale

Potential Impairment

Data Source

Fish kill investigation: Iowa DNR

Metals: Aluminum

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

2018

Impairment Rationale

Violations of chronic criterion

Data Source

Ambient monitoring: adjacent state

TMDL Priority

Tier IV

Class HH

Human Health -

Fully Supported

Impairment Delistings

No delistings for this assessment cycle.

Documentation

Assessment Summary

The Class A1 use was assessed as "not supported" due to high levels of indicator bacteria (fecal coliforms) reported by the Illinois EPA. The Class BWW1 use was assessed as "not supported" due to chronic Aluminum violations and due to a fish kill attributed to natural causes. The Class HH use was assessed as "fully supported" based on the results of fish tissue and water quality monitoring data. The results of interstate consultation via the UMRBA Water Quality Task Force in February 2016 were also used to develop this assessment. The water quality monitoring data collected at the IEPA site L-04 were also used to assess segment IA 02-ICM-619.

Assessment Explanation

Data Sources:

Data Source	Data Source ID	Data Type	Data Age	Site ID	Site Name	Site Description
IEPA	10	WQ	CY 2018-2020	99990020	Mississippi River
Iowa DNR	6	FT	See Below	131	Mississippi River	downstream of Muscatine
Iowa DNR	6	FT	See Below	170	Mississippi River	at Linwood
Iowa DNR	6	FT	See Below	362	Mississippi River	Montpelier

Class A1 - Indicator Bacteria:

The Class A1 use remains assessed as “not supported” based on the impairment of primary contact recreation use identified for this segment of the Upper Mississippi River by the Illinois EPA for the 2016 Section 303(d) listing cycle. The Illinois EPA identified an impairment of primary contact recreation use in this river segment due to high levels of indicator bacteria (fecal coliforms). This assessment was developed as a result of interstate consultation on Section 303(d) listing conducted through the Upper Mississippi River Basin Association’s “Water Quality Task Force” in June 2016.

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
99990020	10	8 / 2	7.2	8.1	7.7	0	3	NO	Evaluated	Full

Class BWW1 - Conventional 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
99990020	10	Ammonia	8 / 2	0.05	0.39	0.14	NA	0 / 0	3	NO	Evaluated	Full
99990020	10	Chloride	10 / 2	22	33.4	26.6	NA	0 / 0	3	NO	Monitored	Full
99990020	10	Dissolved Oxygen	8 / 2	6.2	13.1	10.1	0	NA / NA	3	NO	Evaluated	Full
99990020	10	pH	8 / 2	7.2	8.1	7.7	0	NA / NA	3	NO	Evaluated	Full
99990020	10	Sulfate	10 / 2	17.3	37.3	28	0	NA / NA	3	NO	Monitored	Full
99990020	10	Temperature	8 / 2	0.38	25	12.95	0	NA / NA	3	NO	Evaluated	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
99990020	10	Aluminum	10 / 3	2620	812	476	1 / 2	YES	Monitored	Not
99990020	10	Arsenic	10 / 3	1.86	1.04	0.99	0 / 0	NO	Monitored	Full
99990020	10	Cadmium	10 / 3	1.5	1.5	1.5	0 / 0	NO	Monitored	Full
99990020	10	Chromium	10 / 3	2.5	1.4	1.5	0 / 0	NO	Monitored	Full
99990020	10	Copper	9 / 3	5.25	2.85	2.01	0 / 0	NO	Evaluated	Full
99990020	10	Lead	10 / 3	2.5	2	2.5	0 / 0	NO	Monitored	Full
99990020	10	Nickel	10 / 3	4.7	1.3	1	0 / 0	NO	Monitored	Full
99990020	10	Phenols	10 / 3	6.22	3.81	3.9	0 / 0	NO	Monitored	Full
99990020	10	Selenium	10 / 3	3.5	2.3	2.5	0 / 0	NO	Monitored	Full
99990020	10	Silver	10 / 3	1.5	1.5	1.5	0 / 0	NO	Monitored	Full
99990020	10	Zinc	10 / 3	2.5	2.5	2.5	0 / 0	NO	Monitored	Full

Class BWW1 - Fish kill Assessment:

The Class BWW1 use assessment based on the 2015 fish kill placed this segment in Category 3b. Because the cause of the fish kill was not identified, or the fish kill was attributed to a non-pollutant cause (e.g., winterkill), the assessment type is “evaluated.” Segments assessed using “evaluated” assessments are placed in Category 3b and are added to the state list of waters in need of further investigation (WINOFI). If no additional fish kills are reported in the segment for a 10-year period (2025), the Category will be changed from 3b to 3a (not assessed).

Details about the 2015 fish kill can be found here: https://programs.iowadnr.gov/fishkill/Events/918

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
99990020	10	Arsenic	10 / 3	3.74	1.67	1.58	0	NO	Monitored	Full
99990020	10	Cadmium	10 / 3	2.29	1.44	1.5	8	NO	Monitored	Full
99990020	10	Chromium	10 / 3	3.72	1.81	1.28	0	NO	Monitored	Full
99990020	10	Copper	9 / 3	5.25	2.85	2.01	0	NO	Evaluated	Full
99990020	10	Nickel	10 / 3	5.3	2.6	2	0	NO	Monitored	Full
99990020	10	Phenols	10 / 3	6.22	3.81	3.9	4	NO	Monitored	Full
99990020	10	Selenium	10 / 3	3.5	2.3	2.5	6	NO	Monitored	Full
99990020	10	Zinc	10 / 3	19.5	8.9	7.5	1	NO	Monitored	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)
170	whole	2016	common carp	3	43.1	0.05	0.06	0.06
170	fillet	2018	channel catfish	3	42.7		0.03	0.06
170	fillet	2018	common carp	3	57.2		0.02	0.08
131	fillet	2018	channel catfish	3	44.1		0.02	0.07
131	fillet	2018	common carp	3	64.9		0.02	0.07
131	fillet	2018	common carp	1	50.4		0.02	0.15
362	tissue plug	2019	walleye	2	50.3	0.179
362	tissue plug	2020	bluegill	20	18.6	0.093
362	tissue plug	2020	crappie spp.	20	29.8	0.132
362	tissue plug	2020	flathead catfish	3	40.3	0.169
362	tissue plug	2020	freshwater drum	20	43.3	0.219
362	tissue plug	2019	largemouth bass	20	32.6	0.176
362	tissue plug	2020	northern pike	13	63.9	0.14
362	tissue plug	2020	walleye	14	47.9	0.207
362	tissue plug	2020	white bass	20	28. 9	0.14
Support Level	Full

Monitoring and Methods

Assessment Key Dates

7/1/2019

Fish Tissue Monitoring

1/29/2015

Fish Kill

3/5/2018

Fixed Monitoring Start Date

6/25/2020

Fixed Monitoring End Date

7/21/2016

Fish Tissue Monitoring

7/1/2020

Fish Tissue Monitoring

10/29/2018

Fish Tissue Monitoring

Methods

120

Surveys of fish and game biologists/other professionals

140

Incidence of spills and/or fish kills

230

Fixed station physical/chemical (conventional plus toxic pollutants)

260

Fish tissue analysis

420

Indicator bacteria monitoring

860

Other Agencies/Organizations provided monitoring data