Long Dick Creek IA 03-SSK-960

mouth (S18 T85N R23W Story Co.) to N. line of S34 T86N R23W Hamilton Co.

Assessment Cycle

2024

Release Status

Final

Data Collection Period

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.

Overall IR Category: 5 - Water is impaired or threatened and a TMDL is needed.
Trend: Unknown

Created: 11/1/2023 8:12:56 AM
Updated: 12/29/2023 12:13:44 PM

Assessment conducted in accordance with Iowa's 2024 IR methodology

Use Support

Class A1

Recreation

Primary contact

Presumptive Use

WINOFI

Further Investigation Needed

Support Level

Water in Need of Further Investigation (WINOFI)

Impairment Code

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

Cause Magnitude

Moderate

Status

New

Source

Unknown: Source Unknown

Source Confidence

Low

Cycle Added

2024

Impairment Rationale

Potential Impairment

Data Source

Special project/study

Class BWW2

Aquatic Life

Warm Water Type 2

Not Supported

Impairments

Support Level

Not Supported

Impairment Code

5b-t - Biological - tentative

Cause Magnitude

Moderate

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 presumptive Class A1 use was assessed as "WINOFI" based on E. coli monitoring data. The Class BWW2 use was assessed as “not supported” based on biological sampling data.

Assessment Explanation

Data Sources:

Data Source	Data Source ID	Data Type	Data Age	Site ID	Site Name	Site Description
Prairie Rivers/City of Ames	26	WQ	CY 2020-2022	99990167	Long Dick Creek
Iowa DNR	6	BIO	See Below	115	Long Dick Creek	Roland – LDC1
Iowa DNR	6	BIO	See Below	116	Long Dick Creek	Roland – Old LDC2

Presumptive Class A1 - Indicator Bacteria:

Site ID

Data Source ID

# Samples per Year (2020/ 2021/2022)

2020 Geometric Mean

2021 Geometric Mean

2022 Geometric Mean

Violates Annual Geometric Mean?

# 2020 SSM violations / SSM Violations needed for impairment

# 2021 SSM violations / SSM Violations needed for impairment

# 2022 SSM violations / SSM Violations needed for impairment

Violates Annual SSM Significantly >10% Rule?

Assessment Type

Support Level

99990167

7/6/8

487

392

430

YES

6 / 3

4 / NA

6 / 3

YES

Evaluated

WINOFI

Class BWW2 - Biological Sampling:

Benthic Macroinvertebrates:

BioNet Site ID	Date	Drainage Area (mi2)	Ecoregion	Major Drainage/Thermal	BM Sample Gear	BMIBI score	BMIBI Class	47b BMIBI BIT	BMIBI Pass/Fail
115	9/25/08	32	47b	MS/WW	ArtSub	40	Fair	62	Fail
116	9/24/03	26	47b	MS/WW	Surb	44	Fair	62	Fail
115	9/23/03	32	47b	MS/WW	ArtSub	33	Fair	62	Fail

Fish:

BioNet Site ID	Date	Drainage Area (mi2)	Ecoregion	Major Drainage/Thermal	Riffle Stream?	FIBI score	FIBI Class	47b FIBI BIT	FIBI Pass/Fail
115	9/25/08	32	47b	MS/WW	No	44	Fair	32	Pass
116	9/24/03	26	47b	MS/WW	Yes	33	Fair	53	Fail
115	9/23/03	32	47b	MS/WW	No	34	Fair	32	Pass

Overall:

Community	Assessment Type	Assessment Result	Support Level	IR Category	Reason
Benthic Macroinvertebrates	Evaluated	Fail (0/3)	Not
Fish	Evaluated	Pass (2/3)	Full		Assessment was evaluated because it included samples
Overall	Evaluated	Fail	Not	5bt	not collected in a recent five-year period.

Monitoring and Methods

Assessment Key Dates

9/23/2003

Biological Monitoring

9/24/2003

Biological Monitoring

9/25/2008

Biological Monitoring

4/15/2020

Monitoring Start

10/19/2022

Monitoring End

Methods

150

Monitoring data more than 5 years old

315

Regional reference site approach

320

Benthic macroinvertebrate surveys

330

Fish surveys

420

Indicator bacteria monitoring

860

Other Agencies/Organizations provided monitoring data