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
- 2022
- 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
- 12/27/2021 10:38:46 AM
- Updated
- 1/5/2022 2:21:17 PM
Assessment Summary
The Class A1 use was assessed as "not 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. 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
Data Sources: Data Source Data Source ID Data Type Data Age Site ID Site Name Site Description Iowa DNR 6 WQ CY 2018-2020 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 per Year (2018/ 2019/2020) 2018 Geometric Mean 2019 Geometric Mean 2020 Geometric Mean Violates Annual Geometric Mean? # 2018 SSM violations / SSM Violations
needed for impairment # 2019 SSM violations / SSM Violations
needed for impairment # 2020 SSM violations / SSM Violations
needed for impairment Violates Annual SSM Significantly >10%
Rule? Assessment Type Support Level 10810001 6 8/6/8 488 310 227 YES 4 / 3 3 / NA 4 / 3 YES Monitored Not Class A - pH Site ID Data Source ID # Samples / # Years Minimum Value Maximum Value Mean Value # Violations Violations needed for impairment Violates Significantly >10% Rule? Assessment Type Support Level 10810001 6 36 / 3 7.1 8.6 8.1 0 7 NO Monitored Full Class BWW1 -
Conventional Parameters: Site ID Data Source ID Parameter Name # Samples / # Years Minimum Value Maximum Value Mean Value # Violations # Acute / Chronic Violations Violations needed for impairment Violates Significantly >10% Rule? Assessment Type Support Level 10810001 6 Ammonia 36 / 3 0.025 1.3 0.1 NA 0 / 0 7 NO Monitored Full 10810001 6 Chloride 36 / 3 9.6 63 24.6 NA 0 / 0 7 NO Monitored Full 10810001 6 Dissolved Oxygen 36 / 3 7.3 14.9 10.3 0 NA / NA 7 NO Monitored Full 10810001 6 pH 36 / 3 7.1 8.6 8.1 0 NA / NA 7 NO Monitored Full 10810001 6 Sulfate 36 / 3 15 140 50 0 NA / NA 7 NO Monitored Full 10810001 6 Temperature 36 / 3 0 27.3 11.1 0 NA / NA 7 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 >1 Acute / Chronic Violation Assessment Type Support Level 10810001 6 Aluminum 14 / 3 3 0.821 0.835 0 / 0 NO Monitored Full 10810001 6 Arsenic 13 / 3 4 2.3 2.2 0 / 0 NO Monitored Full 10810001 6 Cadmium 13 / 3 0.05 0.03 0.02 0 / 0 NO Monitored Full 10810001 6 Chromium 13 / 3 1.3 0.7 0.8 0 / 0 NO Monitored Full 10810001 6 Lead 13 / 3 0.2 0.1 0.1 0 / 0 NO Monitored Full 10810001 6 Nickel 13 / 3 4.4 3.3 3.2 0 / 0 NO Monitored Full 10810001 6 Silver 13 / 3 0.025 0.025 0.025 0 / 0 NO Monitored Full 10810001 6 Zinc 13 / 3 5.7 2.6 2.1 0 / 0 NO Monitored Full Site ID Date Drainage Area (mi2) Ecoregion Major Drainage BM Sample Gear BMIBI score BMIBI Class 47b BMIBI BIT BMIBI Pass/Fail 222 8/20/19 709 47b MS Floating Art Sub 56 Good 62 Fail 222 8/11/16 709 47b MS Floating Art Sub 63 Good 62 Pass 222 7/27/15 709 47b MS Floating Art Sub 69 Good 62 Pass Overall: Community Assessment Type Assessment Result Support Level IR Category Reason Benthic
Macroinvertebrates Evaluated Pass (2/3) Full Assessment was evaluated
because the drainage area of the site is Overall Evaluated Pass Full 1 greater than the
calibrated range. Class HH - Fish
Tissue Sampling: Site ID Biopart Year Species # in sample / # of samples Avg Length (cm) (Avg) Hg (ppm) Chlordane (ppm) Sum PCBs (ppm) 82 fillet 2012 channel catfish 3 44 0.147 0.03 0.09 82 tissue plug 2016 walleye 3 53.6 0.25
Support Level Full
Class BWW1 - Biological Sampling:
Benthic Macroinvertebrates:
Assessment Key Dates
7/27/2015 | Biological Monitoring |
1/10/2018 | Fixed Monitoring Start Date |
12/3/2020 | Fixed Monitoring End Date |
8/11/2016 | Biological Monitoring |
8/25/2016 | Fish Tissue Monitoring |
8/20/2019 | Biological Monitoring |
6/24/2008 | TMDL Completed |
7/1/2012 | 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 |