Long Dick Creek IA 03-SSK-2007

N. line of S34 (SE1/4) T86N R23W Hamilton Co to headwaters in NE1/4 S8 T87N R23W Hamilton Co.

Assessment Cycle

2020

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 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.

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

Created: 6/19/2020 8:08:54 AM
Updated: 10/14/2020 6:18:46 AM

Assessment conducted in accordance with Iowa's 2020 IR methodology

Use Support

Class A1

Recreation

Primary contact

Presumptive Use

Partially Supported

Impairments

Support Level

Partially Supported

Impairment Code

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

Cause Magnitude

Slight

Status

Continuing

Source

Unknown: Source Unknown

Source Confidence

N/A

Cycle Added

2010

Impairment Rationale

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

Data Source

TMDL monitoring: Iowa DNR

TMDL Priority

Tier IV

Class BWW1

Aquatic Life

Warm Water Type 1

Presumptive Use

Partially Supported

Impairments

Support Level

Partially Supported

Impairment Code

5b - Biological impairment or pollutant-caused fish kill - unknown source. No administrative action.

Cause Magnitude

Moderate

Status

Continuing

Source

Agriculture: Intensive Animal Feeding Operations

Source Confidence

N/A

Cycle Added

2006

Impairment Rationale

Pollutant-caused fish kill

Data Source

Fish kill investigation: Iowa DNR

TMDL Priority

Tier III

Support Level

Partially Supported

Impairment Code

5b - Biological impairment or pollutant-caused fish kill - unknown source. No administrative action.

Cause Magnitude

High

Status

Continuing

Source

Agriculture: Land application

Source Confidence

N/A

Cycle Added

2014

Impairment Rationale

Pollutant-caused fish kill

Data Source

Fish kill investigation: Iowa DNR

TMDL Priority

Tier III

Further Investigation Needed

Support Level

Water in Need of Further Investigation (WINOFI)

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

2010

Impairment Rationale

Low Biotic Index

Data Source

Biological monitoring: Iowa DNR WQMA

General Use

General Use water

Not Assessed

Impairment Delistings

No delistings for this assessment cycle.

Documentation

Assessment Summary

The presumptive Class A1 use remains assessed as "partially supported" due to levels of indicator bacteria (E. coli) that exceeded state water quality criteria. The presumptive Class BWW1 use remains assessed as “partially supported” based on multiple fish kill investigations and on biological sampling 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 2008 – 2009	11400004	Long Dick Creek near Ellsworth	Site ldc-2
Iowa DNR	6	BIO	See Below	691	Long Dick Creek	Ellsworth – LDC2

Presumptive Class A1 - Indicator Bacteria: Historical

Site ID	Data Source ID	# Samples / # Years	2008 Geometric Mean	2009 Geometric Mean	Annual Geometric Mean Violation	# Violations	% Violations	Significantly >10% Violations	Assessment Type	Support Level
11400004	6	26 / 2	369	175	Yes	15	58%	Yes	Evaluated	Partial

Presumptive Class BWW1 - 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
691	10/6/08	16	47b	MS/WW	ArtSub	71	Good	62	Pass

Fish:

BioNet Site ID	Date	Drainage Area (mi2)	Ecoregion	Major Drainage/ Thermal	Riffle Stream?	FIBI score	FIBI Class	47b FIBI BIT	FIBI Pass/ Fail
691	10/6/08	16	47b	MS/WW	Yes	24	Poor	53	Fail

Overall:

Community	Assessment Type	Assessment Result	Support Level	Earned IR Category	Actual IR Category	Reason
Benthic Macroinvertebrates	Evaluated	Pass (1/1)	Full
Fish	Evaluated	Fail (0/1)	Not
Overall	Evaluated	Fail	Partial	3bu	3bu	Assessment was evaluated because the drainage area of the site was smaller than the calibrated range.

Presumptive Class BWW1 – Fish kill Assessment:

The presumptive Class BWW1 aquatic life use assessment based on the 2004 and 2011 fish kills resulted in two Category 5b impairments because

there were two distinct causes. The fish kills were caused by a “pollutant” or were suspected to be caused by a “pollutant”; therefore, the presumptive

Class BWW1 use was considered impaired. Because the sources of the pollutants were not identified and/or the enforcement actions taken against the

responsible party have not been resolved, the presumptive Class BWW1 use was placed in Category 5b. Due to uncertainty regarding the recovery of the

aquatic life following the fish kill, any existing fish kill 5b impairment will remain in Category 5b until more recent sampling has shown recovery of the

aquatic community or the responsible party has paid restitution.

More details about the 2011 fish kill can be found here: https://programs.iowadnr.gov/fishkill/Events/834

More details about the 2004 fish kill can be found here: https://programs.iowadnr.gov/fishkill/Events/599

Monitoring and Methods

Assessment Key Dates

8/4/2011

Fish Kill

7/28/2009

Non-fixed Monitoring End Date

10/6/2008

Biological Monitoring

1/7/2008

Non-fixed Monitoring Start Date

4/19/2004

Fish Kill

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

220

Non-fixed station physical/chemical monitoring (conventional pollutant only)

315

Regional reference site approach

320

Benthic macroinvertebrate surveys

330

Fish surveys

420

Indicator bacteria monitoring