South Raccoon River IA 04-RAC-1181
mouth (S21 T78 R27W Dallas Co.) to confluence with Middle Raccoon R. in S9 T78N R29W near Redfield in Dallas Co
- Assessment Cycle
- 2022
- Release Status
- Final
- Data Collection Period
- Overall IR Category
- 5 - Water is impaired or threatened and a TMDL is needed.
- Trend
- Unknown
- Created
- 12/27/2021 10:49:13 AM
- Updated
- 12/27/2021 10:51:10 AM
Assessment Summary
The Class A1 use was assessed as "not supported" due to levels of indicator bacteria (E. coli) that violated state water quality criteria. The Class BWW1 use was assessed as "fully supported” based on water quality monitoring data and on biological sampling data. All other designated uses were "not assessed."
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 10250001 South Raccoon River near Redfield
Iowa DNR 6 BIO See Below 930 South
Raccoon River Nations
Bridge County Park - Stuart 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 10250001 6 6/7/8 467 146 330 YES 3 / NA 3 / 3 3 / 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 10250001 6 36 / 3 7.4 8.6 8.2 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 10250001 6 Ammonia 36 / 3 0.02 0.42 0.06 NA 0 / 0 7 NO Monitored Full 10250001 6 Chloride 36 / 3 12 25 16 NA 0 / 0 7 NO Monitored Full 10250001 6 Dissolved Oxygen 36 / 3 7.6 14.2 10.8 0 NA / NA 7 NO Monitored Full 10250001 6 pH 36 / 3 7.4 8.6 8.2 0 NA / NA 7 NO Monitored Full 10250001 6 Sulfate 36 / 3 14 34 23 0 NA / NA 7 NO Monitored Full 10250001 6 Temperature 36 / 3 0 29.8 12.4 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 10250001 6 Aluminum 14 / 3 28 2.98 0.45 0 / 0 NO Monitored Full 10250001 6 Arsenic 13 / 3 4.3 2.1 1.9 0 / 0 NO Monitored Full 10250001 6 Cadmium 13 / 3 0.025 0.025 0.025 0 / 0 NO Monitored Full 10250001 6 Chromium 13 / 3 1.3 0.7 0.9 0 / 0 NO Monitored Full 10250001 6 Lead 13 / 3 0.2 0.1 0.1 0 / 0 NO Monitored Full 10250001 6 Nickel 13 / 3 4.3 2.9 2.9 0 / 0 NO Monitored Full 10250001 6 Silver 13 / 3 0.025 0.025 0.025 0 / 0 NO Monitored Full 10250001 6 Zinc 13 / 3 3.7 1.6 1.5 0 / 0 NO Monitored Full Site ID Date Drainage Area (mi2) Ecoregion Major Drainage BM Sample Gear BMIBI score BMIBI Class 47f BMIBI BIT BMIBI Pass/Fail 930 7/17/19 988 47f MS Floating Art Sub 76 Excellent 51 Pass Overall: Community Assessment Type Assessment Result Support Level IR Category Reason Benthic
Macroinvertebrates Evaluated Pass (1/1) Full Assessment was evaluated
because the drainage area of the site is Overall Evaluated Pass Full 1 greater than the
calibrated range.
Class BWW1 - Biological Sampling:
Benthic Macroinvertebrates:
Class HH - No Data
Assessment Key Dates
1/3/2018 | Fixed Monitoring Start Date |
12/8/2020 | Fixed Monitoring End Date |
7/17/2019 | Biological Monitoring |
Methods
230 | Fixed station physical/chemical (conventional plus toxic pollutants) |
315 | Regional reference site approach |
320 | Benthic macroinvertebrate surveys |
420 | Indicator bacteria monitoring |