Middle Raccoon River IA 04-RAC-1191

from Redfield Dam (S4 T78N R29W Dallas Co.) to Panora DW intake

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 2018 - 2020
Stream/River Water Quality Data	CY 2018 - 2020
Lake Water Quality Data	CY 2016 - 2020
Biological Sampling Data	CY 2016 - 2020*
Fish Kill Data	CY 2016 - 2020
Fish Tissue Sampling Data	CY 2016 - 2020
Continuous Dissolved Oxygen Sampling Data	CY 2016 - 2020
*Biological sites sampled in both 2015 and 2019 were also assessed.

Open Segment Map
View assessment methodology in new window

Cycle: 2022
Release Status: Final
Overall IR: 3 - Insufficient data exist to determine whether any designated uses are met.
Trend: Unknown
Created: 12/28/2021 2:14:13 PM
Updated: 1/13/2022 1:10:30 PM

Use Support

Class A1

Recreation - Primary contact

Not Assessed

Class BWW1

Aquatic Life - Warm Water Type 1

WINOFI

Biological: low fish IBI

Support Level

Further Investigation Needed

Impairment Code

3b-c - Use potentially biologically impaired based on calibrated IBI metrics.

Cause Magnitude

Slight

Status

Continuing

Source

Unknown: Source Unknown

Source Confidence

Low

Cycle Added

2016

Impairment Rationale

Low Biotic Index

Data Source

Biological monitoring: Iowa DNR Fisheries

Class HH

Human Health -

Not Assessed

Impairment Delistings

No delistings for this assessment cycle.

Documentation

Assessment Summary

The Class BWW1 use was assessed as "WINOFI" based on biological sampling data. 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	See Below	1055	Middle Raccoon River	Lenon Mills Dam – MR001
Iowa DNR	6	BIO	See Below	1091	Middle Raccoon River	Linden– MR002

Class A1 - No Data

Class BWW1 - Biological Sampling:

Fish:

BioNet Site ID	Date	Drainage Area (mi2)	Ecoregion	Major Drainage/Thermal	Riffle Stream?	FIBI score	FIBI Class	47f FIBI BIT	FIBI Pass/ Fail
1091	8/3/11	485	47f	MS/WW	NA	33	Fair	36	Fail
1055	8/2/11	434	47f	MS/WW	NA	26	Fair	36	Fail

Overall:

Community	Assessment Type	Assessment Result	Support Level	IR Category	Reason
Fish	Evaluated	Fail (0/2)	WINOFI	3bc	Assessment was evaluated because it included samples not collected in the last five years and the samples were collected in the same year.

Class HH - No Data

Monitoring and Methods

Assessment Key Dates

8/2/2011

Biological Monitoring

8/3/2011

Biological Monitoring

Methods

150

Monitoring data more than 5 years old

315

Regional reference site approach

330

Fish surveys