2018 assessment for English River

English River IA 02-IOW-672

from confluence with Ramsey Creek (S14 T77N R8W Washington Co.) to confluence with South English R. in S6 T77N R9W Washington Co.

2018
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
View assessment methodology in new window

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 2:50:51 PM by

Updated

5/13/2019 2:52:46 PM by

Use Support

Class A1

Recreation - Primary contact

Not Assessed

Class BWW1

Aquatic Life - Warm Water Type 1

Fully Supported

Class HH

Human Health -

Not Assessed

General Use

General Use water -

Not Assessed

303(d) Delistings for this Cycle

No delistings for this assessment cycle.

Documentation

Assessment Summary

The Class B(WW1) aquatic life uses remain assessed (evaluated) as "fully supporting" based on biological data collected in 2002 as part of an DNR Fisheries stream sampling project: Manchester research station. The Class A1 (primary contact recreation) and Class HH (human health/fish consumption) uses remain "not assessed" due to the lack of data upon which to base an assessment.

Assessment Explanation

The Class B(WW1) aquatic life uses remain assessed (evaluated) as "fully supporting" based on biological data collected in 2002 as part of an DNR Fisheries stream sampling project: Manchester research station. A series of biological metrics which reflect stream water quality and habitat integrity were calculated from the Fisheries sampling data. The biological metrics are based on the numbers and types of fish species that were collected in the stream sampling reach. The biological metrics were combined to make a fish community index of biotic integrity (FIBI). The index ranks the biological integrity of a stream sampling reach on a rising scale from 0 (minimum) to 100 (maximum). The 2002 evaluated FIBI was 34 (fair). The aquatic life use support was assessed (evaluated) as fully supporting (=FS), based on a comparison of the FIBI score 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 FIBI BIC for this ecoregion is 36 and this segment passed the FIBI BIC using the uncertainty adjustment value (UAV) of seven points applied to single sample assessments.

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 a single sample collected in 2002. Additionally, because these data are now considered too old (greater than five years) to accurately characterize current water quality conditions, the assessment category is considered “evaluated” (indicating an assessment with relatively lower confidence) as opposed to "monitored" (indicating an assessment with relatively higher confidence).

The Class A1 (primary contact recreation) and Class HH (human health/fish consumption) uses remain "not assessed" due to the lack of data upon which to base an assessment.

Monitoring and Methods

Assessment Key Dates

8/9/2002

Biological Monitoring

Methods

150

Monitoring data more than 5 years old

315

Regional reference site approach

330

Fish surveys