Maple River IA 06-LSR-1581

mouth (S17 T83N R44W Monona Co.) to confluence with unnamed tributary approximately 1 mile east of Danbury in SW 1/4 NE 1/4 S26 T86N R42W Woodbury 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: 9/22/2020 7:21:39 AM
Updated: 10/13/2020 2:36:49 PM

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

Low

Cycle Added

2008

Impairment Rationale

Geometric mean criterion exceeded

Data Source

Ambient monitoring: Iowa DNR-rivers

TMDL Priority

Tier III

Class BWW1

Aquatic Life - Warm Water Type 1

Not Supported

Biological: low fish & invert IBIs- cause unknown

Support Level

Further Investigation Needed

Impairment Code

3b-u - Use potentially biologically impaired based on uncalibrated IBI metrics.

Cause Magnitude

Moderate

Status

Continuing

Source

Unknown: Source Unknown

Source Confidence

Low

Cycle Added

2006

Impairment Rationale

Low Biotic Index

Data Source

Biological monitoring: Iowa DNR WQMA

Metals: Selenium

Support Level

Not Supported

Impairment Code

5a - Pollutant-caused impairment. TMDL needed.

Cause Magnitude

Moderate

Status

New

Source

Unknown: Source Unknown

Source Confidence

Low

Cycle Added

2020

Impairment Rationale

Violations of chronic criterion

Data Source

Ambient monitoring: Iowa DNR-rivers

TMDL Priority

Tier IV

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 remains assessed as "partially supported" due to levels of indicator bacteria (E. coli) that violated state water quality criteria. The Class BWW1 use was assessed as "not supported” due to violations of state water quality chronic criteria for selenium and "partially supported" based on 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
Iowa DNR	6	WQ	CY 2014-2016, CY 2016-2018	10670002	Maple River near Mapleton
Iowa DNR	6	BIO	See Below	366	Maple River	Turin – REMAP #21
Iowa DNR	6	BIO	See Below	415	Maple River	Castana – REMAP #110
Iowa DNR	6	BIO	See Below	926	Maple River	Mapleton

Class A1 - Indicator Bacteria:

Site ID	Data Source ID	# Samples / # Years	2014 Geometric Mean	2015 Geometric Mean	2016 Geometric Mean	Annual Geometric Mean Violation	# Violations	% Violations	Significantly >10% Violations	Assessment Type	Support Level
10670002	6	24 / 3	456	814	691	Yes	17	71%	Yes	Evaluated	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
10670002	6	33 / 3	8.5	8.2	8.3	0	0%	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
10670002	6	Ammonia	33 / 3	0.51	0.05	0.02	0 / 0	0% / 0%	No	Monitored	Full
10670002	6	Chloride	36 / 3	38	17	16	0 / 0	0% / 0%	No	Monitored	Full
10670002	6	Dissolved oxygen	36 / 3	14.4	10.5	10.4	NA / 0	NA / 0%	No	Monitored	Full
10670002	6	pH	33 / 3	8.5	8.2	8.3	0 / NA	0% / NA	No	Monitored	Full
10670002	6	Sulfate	36 / 3	74	51	49	0 / NA	0% / NA	No	Monitored	Full
10670002	6	Temperature	36 / 3	25.9	11.8	10.6	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
10670002	6	Aluminum	9 / 2	20	5.67	1.7	0 / 0	0% / 0%	No	Evaluated	Full
10670002	6	Arsenic	9 / 2	3.1	2	1.8	0 / 0	0% / 0%	No	Evaluated	Full
10670002	6	Cadmium	9 / 2	0.025	0.025	0.025	0 / 0	0% / 0%	No	Evaluated	Full
10670002	6	Chromium	9 / 2	1.2	0.75	0.84	0 / 0	0% / 0%	No	Evaluated	Full
10670002	6	Copper	9 / 2	4.5	1.16	0.65	0 / 0	0% / 0%	No	Evaluated	Full
10670002	6	Lead	9 / 2	0.25	0.094	0.08	0 / 0	0% / 0%	No	Evaluated	Full
10670002	6	Nickel	9 / 2	5.3	2.7	2.3	0 / 0	0% / 0%	No	Evaluated	Full
10670002	6	Selenium	9 / 2	11	7.2	6.6	0 / 7	0% / 78%	Yes	Evaluated	Not
10670002	6	Zinc	9 / 2	4.3	1.58	1.3	0 / 0	0% / 0%	No	Evaluated	Full

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
926	8/30/16	669	47m	MO/WW	Float ArtSub	39	Fair	54	Fail
926	7/30/13	669	47m	MO/WW	Float ArtSub	62	Good	54	Pass
926	9/5/12	669	47m	MO/WW	ArtSub	34	Fair	54	Fail

Fish:

BioNet Site ID	Date	Drainage Area (mi2)	Ecoregion	Major Drainage/ Thermal	Riffle Stream?	FIBI score	FIBI Class	47d/47m FIBI BIT	FIBI Pass/ Fail
415	8/25/04	724	47m	MO/WW	NA	14	Poor	31	Fail
366	8/26/03	732	47d	MO/WW	NA	9	Poor	31	Fail

Overall:

Community	Assessment Type	Assessment Result	Support Level	Earned IR Category	Actual IR Category	Reason
Benthic Macroinvertebrates	Evaluated	Fail (1/3)	Partial
Fish	Evaluated	Fail (0/2)	Not
Overall	Evaluated	Fail	Partial	3bu	3bu	Assessment is evaluated because the drainage areas of the sample 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
10670002	6	Cadmium	9 / 2	0.025	0.025	0.025	9	No	Evaluated	Full
10670002	6	Chromium	9 / 2	1.2	0.75	0.84	0	No	Evaluated	Full
10670002	6	Copper	9 / 2	4.5	1.16	0.65	0	No	Evaluated	Full
10670002	6	Nickel	9 / 2	5.3	2.7	2.3	0	No	Evaluated	Full
10670002	6	Selenium	9 / 2	11	7.2	6.6	0	No	Evaluated	Full
10670002	6	Zinc	9 / 2	4.3	1.58	1.3	0	No	Evaluated	Full

Monitoring and Methods

Assessment Key Dates

1/8/2014

Fixed Monitoring Start Date

12/7/2016

Fixed Monitoring End Date

8/26/2003

Biological Monitoring

8/25/2004

Biological Monitoring

9/5/2012

Biological Monitoring

7/30/2013

Biological Monitoring

8/30/2016

Biological Monitoring

1/5/2016

Fixed Monitoring Start Date

12/5/2018

Fixed Monitoring End Date

Methods

150

Monitoring data more than 5 years old

230

Fixed station physical/chemical (conventional plus toxic pollutants)

315

Regional reference site approach

320

Benthic macroinvertebrate surveys

330

Fish surveys

420

Indicator bacteria monitoring