Tetes Des Morts Creek IA 01-TRK-122

from confluence with Lux Cr. (S7 T87N R4E Jackson Co.) to confluence with unnamed tributary in SW 1/4 NE 1/4 S32 T88N R3E Dubuque 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
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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 8:12:24 AM
Updated: 1/9/2024 9:41:49 AM

Use Support

Class A1

Presumptive Use

Recreation - Primary contact

Not Supported

Bacteria: Indicator Bacteria- E. coli

Support Level

Not Supported

Impairment Code

5p - Impairment occurs on a waterbody with a presumptive A1 or B(WW1) use.

Cause Magnitude

High

Status

Continuing

Source

Unknown: Source Unknown

Source Confidence

N/A

Cycle Added

2012

Impairment Rationale

Geometric mean criterion exceeded

Data Source

Watershed project monitoring

TMDL Priority

Tier III

Class BWW2

Aquatic Life - Warm Water Type 2

Fully Supported

Impairment Delistings

No delistings for this assessment cycle.

Documentation

Assessment Summary

The presumptive Class A1 use was assessed as “not supported” due to violations of Iowa water quality criteria for indicator bacteria (E. coli). The Class BWW2 use was assessed as "fully supported" based on biological sampling data and on the trout reproduction in Iowa streams summary prepared by the DNR Fisheries Bureau. DNR is unsure if this segment is a CW or WW stream; however, this segment will continue to be designated as a WW segment until a UAA is completed.

Assessment Explanation

Data Sources:

Data Source	Data Source ID	Data Type	Data Age	Site ID	Site Name	Site Description
Iowa DNR	6	WQ	CY 2010-2011	13490005	Tetes des Morts at 266 Ave	Site 6
Iowa DNR	6	WQ	CY 2010-2011	13490006	Tetes des Morts at 248 Ave	Site 7
Iowa DNR	6	WQ	CY 2010-2011	13490007	Tetes des Morts at 239 Ave	Site 8
Iowa DNR	6	BIO	See Below	492	Tetes des Morts Creek	REMAP #151

Presumptive Class A1 - Indicator Bacteria: Historical

Site ID	Data Source ID	# Samples / # Years	2010 Geometric Mean	2011 Geometric Mean	Annual Geometric Mean Violation	# Violations	% Violations	Significantly >10% Violations	Assessment Type	Support Level
13490005	6	22 / 2	1605	938	Yes	19	86%	Yes	Evaluated	Not
13490006	6	24 / 2	1295	613	Yes	21	88%	Yes	Evaluated	Not
13490007	6	24 / 2	1520	630	Yes	20	83%	Yes	Evaluated	Not

Class BWW2 - Biological Sampling:

Fish:

BioNet Site ID	Date	Drainage Area (mi2)	Ecoregion	Major Drainage/Thermal	Riffle Stream?	FIBI score	FIBI Class	52bFIBI BIT	FIBI Pass/Fail
492	7/28/22	3.9	52b	MS/WW	NA	80	Excellent	52	Pass

Overall Assessment:

Community	Assessment Type	Assessment Result	Support Level	IR Category	Reason
Fish	Evaluated	Pass (1/1)	FS		Assessment was evaluated because it was based on single FIBI score
Overall	Evaluated	Pass	FS	1	and the drainage area of this site is less than the calibrated range.

Class BWW2 - Trout Natural Reproduction:

Even though Tetes Des Morts Creek is classified as a BWW2 stream, based on the January 2024 trout reproduction in Iowa streams summary prepared by the DNR Fisheries Bureau, the Class BWW2 use of Tetes Des Morts Creek was assessed as "fully supported.” According to the updated summary, this stream was placed in Category I: streams that exhibit consistent natural reproduction and maintain a wild population of one or more trout species without any stocking.

Monitoring and Methods

Assessment Key Dates

8/3/2010

Monitoring Start

11/1/2011

Monitoring End

1/1/2024

Biological Monitoring

7/28/2022

Biological Monitoring

Methods

150

Monitoring data more than 5 years old

330

Fish surveys

420

Indicator bacteria monitoring