Des Moines River IA 04-UDM-1214

from upper end of Saylorville Reservior to Fraser Dam in S34 T85N R27W Boone 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 2016 - 2018
Stream/River Water Quality Data	CY 2016 - 2018
Lake Water Quality Data	CY 2014 - 2018
Biological Sampling Data	CY 2014 - 2018*
Fish Kill Data	CY 2014 - 2018
Fish Tissue Sampling Data	CY 2014 - 2018
Continuous Dissolved Oxygen Sampling Data	CY 2014 - 2018
*Biological sites sampled in both 2013 and 2017 were also assessed.

Open Segment Map
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Cycle: 2020
Release Status: Final
Overall IR: 5 - Water is impaired or threatened and a TMDL is needed.
Trend: Stable
Created: 9/15/2020 7:09:17 AM
Updated: 10/19/2020 8:57:42 AM

Use Support

Class A1

Recreation - Primary contact

Partially Supported

Bacteria: Indicator Bacteria- E. coli

Support Level

Partially Supported

Impairment Code

5a - Pollutant-caused impairment. TMDL needed.

Cause Magnitude

Slight

Status

Continuing

Source

Unknown: Source Unknown

Source Confidence

N/A

Cycle Added

2008

Impairment Rationale

Single-sample maximum criterion exceeded in significantly > 10% of samples

Data Source

Ambient monitoring: Corps of Engineers/ISU/UI

TMDL Priority

Tier III

Class BWW1

Aquatic Life - Warm Water Type 1

Fully Supported

Class HH

Human Health -

Fully Supported

General Use

General Use water -

Not Assessed

Impairment Delistings

No delistings for this assessment cycle.

Documentation

Assessment Summary

The Class A1 use was assessed as "partially supported" based on levels of indicator bacteria (E. coli) that violated state water quality criteria. The Class BWW1 use was assessed as "fully supported" based on water quality monitoring data and 2010 biological sampling data. The Class HH use was assessed as "fully supported" based on water quality monitoring data.

Assessment Explanation

Sources of Data:

Data Source	Data Source ID	Data Type	Data Age	Site ID	Site Name	Site Description
USACE	12	WQ	CY 2016-2018	17080001	Des Moines River at E26
Iowa DNR	6	BIO	See Below	1088	Des Moines River	Below Boone Waterworks Dam – DR003
Iowa DNR	6	BIO	See Below	1089	Des Moines River	Below Frazier Dam – DR004

Class A1 - Indicator Bacteria:

Site ID	Data Source ID	# Samples / # Years	2016 Geometric Mean	2017 Geometric Mean	2018 Geometric Mean	Annual Geometric Mean Violation	# Violations	% Violations	Significantly >10% Violations	Assessment Type	Support Level
17080001	12	22 / 2	176.95	NA	227.32	Yes	9	41%	Yes	Monitored	Partial

Class A1 - pH:

Site ID	Data Source ID	# Samples / # Years	Maximum Value	Mean Value	Median Value	# Violations	% Violations	Significantly >10% Violations	Assessment Type	Support Level
17080001	12	65 / 3	9.14	8.16	8.2	2	3%	No	Monitored	Full

Class BWW1 - Conventional Parameters:

Site ID	Data Source ID	Parameter Name	# Samples / # Years	Maximum Value	Mean Value	Median Value	# Acute / Chronic Violations	% Acute/ Chronic Violations	Significantly >10% Violations	Assessment Type	Support Level
17080001	12	Ammonia	65 / 3	0.85	0.06	0.02	0 / 1	0% / 2%	No	Monitored	Full
17080001	12	Dissolved oxygen	65 / 3	16.5	9.8	9.1	NA / 0	NA / 0%	No	Monitored	Full
17080001	12	pH	65 / 3	9.14	8.16	8.2	2 / NA	3% / NA	No	Monitored	Full
17080001	12	Temperature	65 / 3	26.9	15	16.6	0 / 0	0% / 0%	No	Monitored	Full

Class BWW1 - Toxic Parameters:

Site ID	Data Source ID	Parameter Name	# Samples / # Years	Maximum Value	Mean Value	Median Value	# Acute / Chronic Violations	% Acute/ Chronic Violations	>1 Acute / Chronic Violation	Assessment Type	Support Level
17080001	12	Cadmium	3 / 1	0.15	0.15	0.15	0 / 0	0% / 0%	No	Evaluated	Full
17080001	12	Copper	7 / 2	1.3	0.8	0.5	0 / 0	0% / 0%	No	Evaluated	Full
17080001	12	Lead	3 / 1	0.5	0.5	0.5	0 / 0	0% / 0%	No	Evaluated	Full
17080001	12	Mercury	3 / 1	0.025	0.0175	0.025	0 / 0	0% / 0%	No	Evaluated	Full

Class BWW1 - Biological Sampling:

Fish:

BioNet Site ID	Date	Drainage Area (mi2)	Ecoregion	Major Drainage/Thermal	Riffle Stream?	FIBI score	FIBI Class	47b FIBI BIT	FIBI Pass/ Fail
1089	9/9/10	5482	47b	MS/WW	Und	52	Good	32	Pass
1088	9/8/10	5560	47b	MS/WW	Und	55	Good	32	Pass

Overall:

Community	Assessment Type	Assessment Result	Support Level	Earned IR Category	Actual IR Category	Reason
Fish	Evaluated	Pass (2/2)	Full	1	1	Assessment is evaluated because it was based on old single-year samples and the drainage areas of the sites were larger than the calibrated range.

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
17080001	12	Cadmium	3 / 1	0.15	0.15	0.15	3	No	All Non-Detect	Full
17080001	12	Copper	7 / 2	1.3	0.8	0.5	4	No	Evaluated	Full
17080001	12	Mercury	3 / 1	0.025	0.0175	0.025	3	No	All Non-Detect	Full

Monitoring and Methods

Assessment Key Dates

12/3/2018

Fixed Monitoring End Date

1/4/2016

Fixed Monitoring Start Date

9/8/2010

Biological Monitoring

9/9/2010

Biological Monitoring

Methods

150

Monitoring data more than 5 years old

230

Fixed station physical/chemical (conventional plus toxic pollutants)

315

Regional reference site approach

330

Fish surveys

420

Indicator bacteria monitoring