Little Sioux River IA 06-LSR-1570
from Highway 3 (S26 T92N R40W Cherokee Co.) to confluence with Waterman Cr. in S26 T94N R39W O'Brien Co.
- Assessment Cycle
- 2020
- Release Status
- Final
- Data Collection Period
- Overall IR Category
- 5 - Water is impaired or threatened and a TMDL is needed.
- Trend
- Stable
- Created
- 9/21/2020 2:27:13 PM
- Updated
- 10/19/2020 7:39:44 AM
Assessment Summary
The Class A1 use was assessed as “partially supported” due to violations of the state water quality criteria for indicator bacteria (E. coli). The Class BWW1 use was assessed as "fully supported" based on water quality monitoring data and on biological sampling data. The Class HH use was assessed as "fully supported" based on water quality monitoring data.
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 10180001 Little Sioux River near Larrabee Iowa DNR 6 BIO See Below 938 Little Sioux River Larrabee 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 10180001 6 10 / 3 155.28 136.08 313.39 Yes 4 40% Yes Evaluated Partial Class
A1 - pH: Site ID Data Source ID # Samples / # Years Maximum Value Mean Value Median Value # Violations % Violations Significantly >10% Violations Assessment Type Support Level 10180001 6 35 / 3 8.9 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 10180001 6 Ammonia 35 / 3 1 0.09 0.02 0 / 0 0% / 0% No Monitored Full 10180001 6 Chloride 36 / 3 29 23 23 0 / 0 0% / 0% No Monitored Full 10180001 6 Dissolved oxygen 36 / 3 15.8 10.5 10.9 NA / 0 NA / 0% No Monitored Full 10180001 6 pH 35 / 3 8.9 8.2 8.2 0 / NA 0% / NA No Monitored Full 10180001 6 Sulfate 36 / 3 80 54 56 0 / NA 0% / NA No Monitored Full 10180001 6 Temperature 36 / 3 26.4 11.6 9.6 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 10180001 6 Aluminum 9 / 2 5.2 1.41 0.8 0 / 0 0% / 0% No Evaluated Full 10180001 6 Arsenic 9 / 2 3.5 2.1 1.8 0 / 0 0% / 0% No Evaluated Full 10180001 6 Cadmium 9 / 2 0.25 0.05 0.025 0 / 0 0% / 0% No Evaluated Full 10180001 6 Chromium 9 / 2 3 1 0.84 0 / 0 0% / 0% No Evaluated Full 10180001 6 Copper 9 / 2 3.8 1.28 1.1 0 / 0 0% / 0% No Evaluated Full 10180001 6 Lead 9 / 2 0.18 0.092 0.08 0 / 0 0% / 0% No Evaluated Full 10180001 6 Nickel 9 / 2 3.6 2.8 2.7 0 / 0 0% / 0% No Evaluated Full 10180001 6 Selenium 9 / 2 2.8 1.8 1.6 0 / 0 0% / 0% No Evaluated Full 10180001 6 Zinc 9 / 2 7.6 2.21 2 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 47a BMIBI BIT BMIBI Pass/ Fail 938 7/18/17 1848 47a MO/WW Hess 74 Good 54 Pass 938 9/23/14 1848 47a MO/WW Float ArtSub 48 Fair 54 Fail 938 8/21/13 1848 47a MO/WW Hess 60 Good 54 Pass 938 8/21/13 1848 47a MO/WW Float ArtSub 55 Fair 54 Pass Overall: Community Assessment Type Assessment Result Support Level Earned IR Category Actual IR Category Reason Benthic
Macroinvertebrates Evaluated Pass (3/4) Full 1 1 Assessment
is evaluated because the drainage area of the sample site was larger than the
calibrated range. 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 10180001 6 Cadmium 9 / 2 0.25 0.05 0.025 8 No Evaluated Full 10180001 6 Chromium 9 / 2 3 1 0.84 0 No Evaluated Full 10180001 6 Copper 9 / 2 3.8 1.28 1.1 0 No Evaluated Full 10180001 6 Nickel 9 / 2 3.6 2.8 2.7 0 No Evaluated Full 10180001 6 Selenium 9 / 2 2.8 1.8 1.6 0 No Evaluated Full 10180001 6 Zinc 9 / 2 7.6 2.21 2 0 No Evaluated Full
Assessment Key Dates
| 1/6/2016 | Fixed Monitoring Start Date |
| 12/6/2018 | Fixed Monitoring End Date |
| 7/18/2017 | Biological Monitoring |
| 8/21/2013 | Biological Monitoring |
| 9/23/2014 | Biological Monitoring |
Methods
| 150 | Monitoring data more than 5 years old |
| 230 | Fixed station physical/chemical (conventional plus toxic pollutants) |
| 315 | Regional reference site approach |
| 320 | Benthic macroinvertebrate surveys |
| 420 | Indicator bacteria monitoring |