North Raccoon River IA 04-RAC-1132
from confluence with Indian Cr. (S24 T87N R36W Sac Co.) to confluence with Cedar Cr. in S25 T88N R36W Sac Co.
- Assessment Cycle
- 2020
- Release Status
- Final
- Data Collection Period
- Overall IR Category
- 4 - Water is impaired or threatened and a TMDL has been completed or is not needed.
- Trend
- Unknown
- Created
- 9/14/2020 8:13:02 AM
- Updated
- 10/13/2020 7:00:55 AM
Assessment Summary
The Class A1 use was assessed as "partially supported" due to levels of indicator bacteria (E. coli) that violated state water quality standards. The Class BWW1 use was assessed as "fully supported" based on biological sampling data and water quality monitoring data. The Class HH (fish consumption) use was assessed as "fully supported" based on fish tissue sampling data and water quality monitoring data. Note: A TMDL for pathogen indicator impairments in the Raccoon River basin was approved by EPA in 2008. Because this TMDL covers the primary Section 303(d) impairment identified for the 2006 IR cycle, this segment was moved from IR Category 5a to IR Category 4a (impaired; TMDL approved) for the 2008 cycle. This waterbody remains in IR Category 4a for the current cycle.
Assessment Explanation
Sources of
Data: Data Source Data Source ID Data Type Data Age Site ID Site Name Site Description Iowa DNR 6 WQ CY 2016-2018 10810001 North Raccoon River near Sac City (DS1) Iowa DNR 6 BIO See Below 222 North Raccoon River Sac City Iowa DNR 6 FT See Below 82 North Raccoon River Downstream of Sac City Class A1 -
Indicator Bacteria: Site ID Data Source ID # Samples / # Years 2016 Geometric Mean 2017 Geometric Mean 2018 Geometric Mean Annual Geometric Mean Violation # Violations % Violations Significantly >10% Violations Assessment Type Support Level 10810001 6 20 / 3 338.26 185.29 488.48 Yes 10 50% Yes Monitored Partial Class A - pH: Site ID Data Source ID # Samples / # Years Maximum Value Mean Value Median Value # Violations % Violations Significantly >10% Violations Assessment Type Support Level 10810001 6 34 / 3 8.6 8.2 8.2 0 0% No Monitored Full Class BWW1 -
Conventional Parameters: Site ID Data Source ID Parameter Name # Samples / # Years Maximum Value Mean Value Median Value # Acute / Chronic Violations % Acute/ Chronic Violations Significantly >10% Violations Assessment Type Support Level 10810001 6 Ammonia 34 / 3 0.75 0.07 0.02 0 / 0 0% / 0% No Monitored Full 10810001 6 Chloride 36 / 3 40 23.5 21.5 0 / 0 0% / 0% No Monitored Full 10810001 6 Dissolved oxygen 36 / 3 15.3 10.2 10.1 NA / 0 NA / 0% No Monitored Full 10810001 6 pH 34 / 3 8.6 8.2 8.2 0 / NA 0% / NA No Monitored Full 10810001 6 Sulfate 36 / 3 120 47 39 0 / NA 0% / NA No Monitored Full 10810001 6 Temperature 36 / 3 25.3 11.7 10.4 0 / 0 0% / 0% No Monitored Full Class BWW1 -
Toxic Parameters: Site ID Data Source ID Parameter Name # Samples / # Years Maximum Value Mean Value Median Value # Acute / Chronic Violations % Acute/ Chronic Violations >1 Acute / Chronic Violation Assessment Type Support Level 10810001 6 Aluminum 9 / 2 3 0.789 0.79 0 / 0 0% / 0% No Evaluated Full 10810001 6 Arsenic 9 / 2 4.5 2.7 2.5 0 / 0 0% / 0% No Evaluated Full 10810001 6 Cadmium 9 / 2 0.025 0.025 0.025 0 / 0 0% / 0% No Evaluated Full 10810001 6 Chromium 9 / 2 1.1 0.71 0.62 0 / 0 0% / 0% No Evaluated Full 10810001 6 Copper 9 / 2 3.7 1.6 1.2 0 / 0 0% / 0% No Evaluated Full 10810001 6 Lead 9 / 2 0.17 0.064 0.06 0 / 0 0% / 0% No Evaluated Full 10810001 6 Nickel 9 / 2 4.2 3 2.7 0 / 0 0% / 0% No Evaluated Full 10810001 6 Selenium 9 / 2 3.6 2.4 2.6 0 / 0 0% / 0% No Evaluated Full 10810001 6 Zinc 9 / 2 5.7 2.06 1.6 0 / 0 0% / 0% No Evaluated Full Class
BWW1 - Biological Sampling: Benthic
Macroinvertebrates: BioNet Site ID Date Drainage Area (mi2) Ecoregion Major Drainage/Thermal BM Sample Gear BMIBI score BMIBI Class 47b BMIBI BIT BMIBI Pass/ Fail 222 8/11/16 709 47b MS/WW Float ArtSub 63 Good 62 Pass 222 7/27/15 709 47b MS/WW Float ArtSub 69 Good 62 Pass
Overall: Community Assessment Type Assessment Result Support Level Earned IR Category Actual IR Category Reason Benthic
Macroinvertebrates Evaluated Pass Full 1 1 Assessment
is evaluated the drainage area of the sample site was larger than the
calibrated range. Class HH – Fish Tissue Sampling: Site ID Date Species Name Biopart # in sample Hg result Hg violation (>0.3)? Assessment Type Support Level 82 8/25/2016 walleye plug 3 0.250 No Monitored Full 82 8/4/2014 smallmouth bass plug 3 0.160 No Monitored Full Class HH-F -
Toxic Parameters: Site ID Data Source ID Parameter Name # Samples / # Years Maximum Value Mean Value Median Value Number of Non - Detects Mean Value > Criterion or MCL Assessment Type Support Level 10810001 6 Cadmium 9 / 2 0.025 0.025 0.025 9 No All Non-Detect Full 10810001 6 Chromium 9 / 2 1.1 0.71 0.62 0 No Evaluated Full 10810001 6 Copper 9 / 2 3.7 1.6 1.2 0 No Evaluated Full 10810001 6 Nickel 9 / 2 4.2 3 2.7 0 No Evaluated Full 10810001 6 Selenium 9 / 2 3.6 2.4 2.6 0 No Evaluated Full 10810001 6 Zinc 9 / 2 5.7 2.06 1.6 0 No Evaluated Full
Assessment Key Dates
| 7/27/2015 | Biological Monitoring |
| 1/6/2016 | Fixed Monitoring Start Date |
| 12/6/2018 | Fixed Monitoring End Date |
| 8/11/2016 | Biological Monitoring |
| 8/4/2014 | Fish Tissue Monitoring |
| 8/25/2016 | Fish Tissue Monitoring |
Methods
| 230 | Fixed station physical/chemical (conventional plus toxic pollutants) |
| 260 | Fish tissue analysis |
| 315 | Regional reference site approach |
| 320 | Benthic macroinvertebrate surveys |
| 420 | Indicator bacteria monitoring |