Middle Raccoon River IA 04-RAC-1195
upend L Panorama to Willow Cr-Guthrie
- Cycle
- 2016
- 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
- 9/20/2016 1:51:34 PM
- Updated
- 11/7/2016 1:44:02 PM
The presumptive Class A1 (primary contact recreation) and Class HH (human health/fish consumption) uses remain "not assessed" (IR 3a) due to the lack of water quality information upon which to base an assessment. The Class B(WW1) aquatic life uses remain assessed (evaluated) as “fully supported” (IR 2a) based on (1) biological data collected in 2005 as part of the IDNR/SHL stream REMAP project and (2) results of USGS water quality monitoring from May to August 2013 at station 05483450 near Bayard, IA.
The presumptive Class A1 (primary contact recreation) and Class HH (human health/fish consumption) uses remain "not assessed" (IR 3a) due to the lack of water quality information upon which to base an assessment. Monitoring for indicator bacteria was not conducted as part of USGS monitoring near Bayard in 2013. The aquatic life uses remain assessed (evaluated) as “fully supported” based on biological data collected in 2005 as part of the IDNR/SHL stream REMAP project. A series of biological metrics which reflect stream water quality and habitat integrity were calculated from the biological sampling data. The biological metrics are based on the numbers and types of benthic macroinvertebrate taxa and fish species collected in the stream sampling reach. The biological metrics were combined to make a fish community index of biotic integrity (FIBI) and a benthic macroinvertebrate index (BMIBI). The indexes rank the biological integrity of a stream sampling reach on a rising scale from 0 (minimum) to 100 (maximum). The 2005 FIBI score was 32 (fair) and the BMIBI score was 53 (fair). The aquatic life use support was assessed 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 FIBI BIC for this ecoregion is 36 and the BMIBI BIC for this ecoregion is 51. This site met the FIBI BIC with the use of the FIBI UAV of 7 points applied to single samples and also passed the BMIBI BIC. The biological impairment criteria were determined from a statistical analysis of data collected at stream ecoregion reference sites from 1994-2008. This aquatic life assessment is considered "evaluated" because there were not two or more samples collected from this segment in multiple years over a five-year period. 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). Despite this change in assessment methodology and assessment type, this waterbody remains in IR Category 2a. Results of USGS water quality monitoring near Bayard, IA, from May to August 2013 also suggest “full support” of the aquatic life uses. No violations of Class B(WW1) water quality criteria occurred in the 12 samples analyzed for ammonia, chloride, dissolved oxygen, pH, sulfate, and temperature.