Mill Creek IA 06-LSR-1615

mouth (S14 T92N R40W Cherokee Co.) to confluence with Whisky Cr. at east line S29 T94N R41W O'Brien 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 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
View assessment methodology in new window

Cycle: 2024
Release Status: Final
Overall IR: 5 - Water is impaired or threatened and a TMDL is needed.
Trend: Unknown
Created: 1/10/2024 1:27:45 PM
Updated: 2/6/2024 9:03:43 AM

Use Support

Class A1

Presumptive Use

Recreation - Primary contact

Not Assessed

Class BWW2

Aquatic Life - Warm Water Type 2

Not Supported

Biological: low fish & invert IBIs- cause unknown

Support Level

Not Supported

Impairment Code

5b-v - Biological - verified

Cause Magnitude

Slight

Status

Continuing

Source

Unknown: Source Unknown

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 Class BWW2 use was assessed as “not supported” based on biological sampling data and on a fish kill investigation. 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	BIO/WQ	See Below	142	Mill Creek	NE of Meriden (REMAP#436)
Iowa DNR	6	BIO	See Below	1203	Mill Creek	Larrabee
Iowa DNR	6	BIO	See Below	1381	Mill Creek	Cherokee (FKF)

Presumptive Class A1 - No Data

Class BWW2 - Biological Sampling:

Benthic Macroinvertebrates:

BioNet Site ID	Date	Drainage Area (mi2)	Ecoregion	Major Drainage/ Thermal	BM Sample Gear	BMIBI score	BMIBI Class	47a BMIBI BIT	BMIBI Pass/Fail
142	7/27/21	259.0	47a	MO/WW	Surber	44	Fair	54	Fail
1203	9/17/19	267.0	47a	MO/WW	Hess	54	Fair	54	Pass
142	9/19/17	259.0	47a	MO/WW	ArtSub	47	Fair	54	Fail

Fish:

BioNet Site ID	Date	Drainage Area (mi2)	Ecoregion	Major Drainage/ Thermal	Riffle Stream?	FIBI score	FIBI Class	47a FIBI BIT	FIBI Pass/Fail
142	7/27/21	259.0	47a	MO/WW	NA	38	Fair	43	Fail
1203	9/17/19	267.0	47a	MO/WW	NA	28	Fair	43	Fail
142	9/19/17	259.0	47a	MO/WW	NA	39	Fair	43	Fail

Overall:

Community	Assessment Type	Assessment Result	Support Level	IR Category	Reason
Benthic Macroinvertebrates	Monitored	Fail (1/3)	Not
Fish	Monitored	Fail (0/3)	Not		Assessment was monitored because the samples used to complete
Overall	Monitored	Fail	Not	5bv	the assessment were collected in a recent five-year period.

Class BWW2 – Fish kill Assessment:

BioNet Site ID	Date	Drainage Area (mi2)	Ecoregion	Major Drainage/ Thermal	Fish per mile	47a REMAP 25 % fish per mile	>47a REMAP 25 % fish per mile?	2024 IR 47a expected fish taxa	Fish Taxa Present % (>50% to pass)
142	9/19/2017	259	47a	MO/WW	1203	496	Yes (Pass)	9/10	90% (Pass)
1203	9/17/2019	267	47a	MO/WW	264	496	No (Fail)	7/10	70% (Pass)
142	7/27/2021	259	47a	MO/WW	2999	496	Yes (Pass)	9/10	90% (Pass)
1381	9/28/22	267.0	47a	MO/WW	18406	496	Yes (Pass)	9/10	90% (Pass)
The Class BWW2 use previously resided in Category 3b (WINOFI) based on a fish kill that occurred in 2013. This segment’s fish community was sampled in 2022 as part of the DNR fish kill follow-up sampling program. The results from this follow-up sampling and comparison to ecoregion averages suggest that the fish community of this segment is similar to non-fish kill impacted streams. Based on the fish kill follow-up sampling results, the Category for the fish kill assessment was changed from 3b to 3a (not assessed).

Class BWW2- Continuous DO Monitoring:

Site ID	Data Source ID	# Days Monitoring (2016)	DO Criteria Type	# 2016 violations/Violations needed for impairment	Violates Annual Significantly >10% Rule?	Assessment Type	Support Level
			24 hr	0/15	No
142	6	98	16 hr	0/15	No	Evaluated	Full

Monitoring and Methods

Assessment Key Dates

8/1/2016

Biological Monitoring

9/17/2019

Biological Monitoring

8/17/2013

Fish Kill

9/19/2017

Biological Monitoring

9/28/2022

Biological Monitoring

7/5/2016

Monitoring Start

10/10/2016

Monitoring End

Methods

120

Surveys of fish and game biologists/other professionals

140

Incidence of spills and/or fish kills

150

Monitoring data more than 5 years old

200

Physical/Chemical Monitoring

315

Regional reference site approach

320

Benthic macroinvertebrate surveys

330

Fish surveys

380

Quantitative physical habitat assessment