Little Sioux River IA 06-LSR-1578
from confluence with Milford Cr. (NW 1/4 S14 T98N R37W Dickinson Co.) to confluence with West Fork Little Sioux R. in S36 T100N R38W Dickinson 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
- 9/22/2020 6:43:03 AM
- Updated
- 10/19/2020 7:32:10 AM
Assessment Summary
The Class A1 use remains assessed as "partially supported" due to levels of indicator bacteria that violated state water quality criteria. The Class BWW1 was assessed as "partially supported” based on biological sampling data. The Class HH use was assessed as "fully supported" based on water quality monitoring.
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 2014-2016, CY 2016-2018 10300001 Little Sioux River near Milford
Iowa DNR 6 BIO See Below 63 Little Sioux River Horseshoe Bend Co. Park - Milford Iowa DNR 6 BIO See Below 1148 Little Sioux River Gravel Re. bridge W of Milford Class A1 - Indicator Bacteria: Site ID Data Source ID # Samples / # Years 2014 Geometric Mean 2015 Geometric Mean 2016 Geometric Mean Annual Geometric Mean Violation # Violations % Violations Significantly >10% Violations Assessment Type Support Level 10300001 6 24 / 23 146 212 255 Yes 12 50% Yes Evaluated Partial Site ID Data Source ID # Samples / # Years Maximum Value Mean Value Median Value # Violations % Violations Significantly >10% Violations Assessment Type Support Level 10300001 6 35 / 3 8.5 8.1 8.1 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 10300001 6 Ammonia 35 / 3 1.1 0.07 0.02 0 / 0 0% / 0% No Monitored Full 10300001 6 Chloride 36 / 3 35 23 23 0 / 0 0% / 0% No Monitored Full 10300001 6 Dissolved oxygen 36 / 3 14.4 10.2 10.7 NA / 0 NA / 0% No Monitored Full 10300001 6 pH 35 / 3 8.5 8.1 8.1 0 / NA 0% / NA No Monitored Full 10300001 6 Sulfate 36 / 3 110 76 75 0 / NA 0% / NA No Monitored Full 10300001 6 Temperature 36 / 3 26.1 12 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 10300001 6 Aluminum 9 / 2 2.7 0.907 0.41 0 / 0 0% / 0% No Evaluated Full 10300001 6 Arsenic 9 / 2 4.4 2.6 2.4 0 / 0 0% / 0% No Evaluated Full 10300001 6 Cadmium 9 / 2 0.025 0.025 0.025 0 / 0 0% / 0% No Evaluated Full 10300001 6 Chromium 9 / 2 1.3 0.72 0.71 0 / 0 0% / 0% No Evaluated Full 10300001 6 Copper 9 / 2 4.5 1.27 0.88 0 / 0 0% / 0% No Evaluated Full 10300001 6 Lead 9 / 2 0.29 0.081 0.06 0 / 0 0% / 0% No Evaluated Full 10300001 6 Nickel 9 / 2 3.9 3.1 3.1 0 / 0 0% / 0% No Evaluated Full 10300001 6 Selenium 9 / 2 3.7 2.2 2 0 / 0 0% / 0% No Evaluated Full 10300001 6 Zinc 9 / 2 2.5 1.4 1.5 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 1148 8/15/17 484 47b MO/WW Float ArtSub 73 Good 62 Pass 63 8/12/14 333 47b MO/WW ArtSub 50 Fair 62 Fail 63 9/29/11 333 47b MO/WW Hess 54 Fair 62 Fail Fish: BioNet Site ID Date Drainage Area (mi2) Ecoregion Major Drainage/ Thermal Riffle Stream? FIBI score FIBI Class 47b FIBI BIT FIBI Pass/ Fail 63 8/12/14 333 47b MO/WW Yes 41 Fair 53 Fail 63 9/30/11 333 47b MO/WW Yes 60 Good 53 Pass Overall: Community Assessment Type Assessment Result Support Level Earned IR Category Actual IR Category Reason Benthic
Macroinvertebrates Evaluated Fail (1/3) Partial Fish Evaluated Fail (1/2) Partial Overall Evaluated Fail Partial 3bc 5bt Assessment
is evaluated because it included samples not collected in the last five years. 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 10300001 6 Cadmium 9 / 2 0.025 0.025 0.025 9 No Evaluated Full 10300001 6 Chromium 9 / 2 1.3 0.72 0.71 0 No Evaluated Full 10300001 6 Copper 9 / 2 4.5 1.27 0.88 0 No Evaluated Full 10300001 6 Nickel 9 / 2 3.9 3.1 3.1 0 No Evaluated Full 10300001 6 Selenium 9 / 2 3.7 2.2 2 0 No Evaluated Full 10300001 6 Zinc 9 / 2 2.5 1.4 1.5 0 No Evaluated Full
Assessment Key Dates
1/13/2014 | Fixed Monitoring Start Date |
12/8/2016 | Fixed Monitoring End Date |
8/12/2014 | Biological Monitoring |
9/29/2011 | Biological Monitoring |
9/30/2011 | Biological Monitoring |
8/15/2017 | Biological Monitoring |
1/5/2016 | Fixed Monitoring Start Date |
12/6/2018 | Fixed Monitoring End Date |
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 |
330 | Fish surveys |
420 | Indicator bacteria monitoring |