South Beaver Creek IA 02-CED-561

mouth (S25 T90N R17W Butler Co.) to confluence with Middle Fork South Beaver Cr. in S28T89R17W Grundy 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 2014 - 2016
Stream/River Water Quality Data	CY 2014 - 2016
Lake Water Quality Data	CY 2012 - 2016
Biological Sampling Data	CY 2012 - 2016*
Fish Kill Data	CY 2012 - 2016
Fish Tissue Sampling Data	CY 2012 - 2016
Continuous Dissolved Oxygen Sampling Data	CY 2012 - 2016
*Biological sites sampled in both 2011 and 2015 were also assessed.

Open Segment Map
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Cycle: 2018
Release Status: Final
Overall IR: 2 - Some of the designated uses are met but there is insufficient data to determine if remaining designated uses are met.
Trend: Unknown
Created: 5/13/2019 1:50:56 PM
Updated: 5/13/2019 1:53:43 PM

Use Support

Class A1

Presumptive Use

Recreation - Primary contact

Not Assessed

Class BWW2

Aquatic Life - Warm Water Type 2

Fully Supported

General Use

General Use water -

Not Assessed

Impairment Delistings

No delistings for this assessment cycle.

Documentation

Assessment Summary

The presumptive Class A1 (primary contact recreation) uses remain "not assessed" due to the lack of information upon which to base an assessment. The Class B(WW2) aquatic life uses remain assessed (evaluated) as "fully supported" based on results of DNR/SHL biological sampling in 1996, 2001, 2008 and 2014.

Assessment Explanation

The Class B(WW2) aquatic life uses are assessed (evaluated) as “fully supporting” based on data collected in 1996, 2001, 2008 and 2014 as part of the DNR/SHL stream biocriteria project. The 1996 BMIBI score was 66 (good) and the 2001 BMIBI score was 74 (good). The 2008 FIBI score was 50 (fair) and the BMIBI score was unavailable. The 2014 FIBI score was 63(good) and the BMIBI score was 41 (fair). The aquatic life use support was assessed (evaluated) as fully supporting (=FS), based on a comparison of the FIBI and BMIBI scores with biological impairment criteria (BIC) established for previous Section 305(b) reports. The biological impairment criteria were determined from a statistical analysis of data collected at stream ecoregion reference sites from 1994-2008. The non-riffle habitat FIBI BIC for this ecoregion is 44 and the artificial substrate BMIBI BIC for this ecoregion is 52. This segment passed the FIBI BIC 2/2 times in the last nine years and passed the BMIBI BIC 2/3 times in the past 21 years.

This aquatic life assessment is now considered "evaluated" based on a change in the 2010 DNR assessment methodology. DNR now requires a segment have two or more biological samples collected from the segment in multiple years over a five-year period to be considered “monitored”. This segment had multiple samples collected in the previous 21 years (1996-2016); however, the multiple samples were not collected during a recent five-year period. Despite this change in assessment methodology and type, this waterbody remains in IR Category 2a.

Monitoring and Methods

Assessment Key Dates

7/30/1996

Biological Monitoring

8/13/2001

Biological Monitoring

9/10/2014

Biological Monitoring

9/3/2008

Biological Monitoring

Methods

150

Monitoring data more than 5 years old

315

Regional reference site approach

320

Benthic macroinvertebrate surveys

330

Fish surveys

380

Quantitative physical habitat assessment