Little Wapsipinicon River IA 01-WPS-399

From impoundment upstream of Hwy 281 at Fairbank (N 1/2 S5 T90N R10W Buchanan Co.) to the Fayette/Bremer county line in NW 1/4 S18 T92N R10W Fayette 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: 3 - Insufficient data exist to determine whether any designated uses are met.
Trend: Unknown

Created: 11/1/2023 8:13:55 AM
Updated: 12/20/2023 2:04:51 PM

Assessment conducted in accordance with Iowa's 2024 IR methodology.

Use Support

Class A1

Recreation

Primary contact

Presumptive Use

Not Assessed

Class BWW2

Aquatic Life

Warm Water Type 2

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

Slight

Status

Continuing

Source

Unknown: Source Unknown

Source Confidence

N/A

Cycle Added

2022

Impairment Rationale

Pollutant-caused fish kill

Data Source

Fish kill investigation: Iowa DNR

Impairment Delistings

No delistings for this assessment cycle.

Documentation

Assessment Summary

The Class BWW2 use was assessed (evaluated) as “WINOFI” based on the results of a fish kill investigation. All other designated uses were "not assessed."

Assessment Explanation

Presumptive Class A1 –No Data

Class BWW2 – Fish kill Assessment:

The BWW2 aquatic life use assessment based on the 2020 fish kill placed this segment in Category 3b. This assessment was “evaluated” because there was a single fish kill on this segment in the last five years. Segments assessed using “evaluated” assessments are placed in Category 3b and are added to the state list of Waters In Need Of Further Investigation (WINOFI). If no additional fish kills are reported in this segment for a 10-year period (2030), the Category will be changed from 3b to 3a (not assessed).

Details about the 2020 fish kill can be found here:https://programs.iowadnr.gov/fishkill/Events/1005

Monitoring and Methods

Assessment Key Dates

9/8/2020

Fish Kill

Methods

120

Surveys of fish and game biologists/other professionals

140

Incidence of spills and/or fish kills