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
- 2022
- Release Status
- Final
- Data Collection Period
- Overall IR Category
- 5 - Water is impaired or threatened and a TMDL is needed.
- Trend
- Stable
- Created
- 12/28/2021 6:28:21 AM
- Updated
- 1/27/2022 9:50:44 AM
Cycle Added | Class | Cause | Data Source | Rationale |
---|---|---|---|---|
2016 | Class BWW1 | Biological: low fish & invert IBIs- cause unknown | Biological monitoring: Iowa DNR WQMA | New data: recovery of fish/invertebrate community |
Assessment Summary
The Class A1 use was assessed as "not supported" due to levels of indicator bacteria that violated state water quality criteria. The Class BWW1 was assessed as "not supported” based 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 10300001 Little Sioux River near Milford
Iowa
DNR 6 BIO See
Below 63 Little Sioux River Horseshoe Bend County Park -
Milford Iowa
DNR 6 BIO See
Below 1148 Little Sioux River Gravel Road Bridge W of Milford 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 10300001 6 1/1/8 3100 440 219 YES 1 / NA 1 / 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 10300001 6 36 / 3 6.8 8.8 7.9 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 10300001 6 Ammonia 36 / 3 0.025 1.1 0.1 NA 0 / 0 7 NO Monitored Full 10300001 6 Chloride 36 / 3 11 28 17 NA 0 / 0 7 NO Monitored Full 10300001 6 Dissolved Oxygen 36 / 3 6.1 15.3 10 0 NA / NA 7 NO Monitored Full 10300001 6 pH 36 / 3 6.8 8.8 7.9 0 NA / NA 7 NO Monitored Full 10300001 6 Sulfate 36 / 3 26 110 66 0 NA / NA 7 NO Monitored Full 10300001 6 Temperature 36 / 3 0 26.5 10.6 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 10300001 6 Aluminum 14 / 3 3.2 0.9 0.5 0 / 0 NO Monitored Full 10300001 6 Arsenic 13 / 3 4.4 2.3 2 0 / 0 NO Monitored Full 10300001 6 Cadmium 13 / 3 0.07 0.03 0.02 0 / 0 NO Monitored Full 10300001 6 Chromium 13 / 3 1.7 0.7 0.7 0 / 0 NO Monitored Full 10300001 6 Lead 13 / 3 0.29 0.12 0.09 0 / 0 NO Monitored Full 10300001 6 Nickel 13 / 3 4.9 3.5 3.2 0 / 0 NO Monitored Full 10300001 6 Silver 13 / 3 0.025 0.025 0.025 0 / 0 NO Monitored Full 10300001 6 Zinc 13 / 3 3.4 2.1 2 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 63 8/4/20 333.4 47b MO Art Sub 65 Good 62 Pass 1148 8/5/17 484 47b MO Floating Art Sub 73 Good 62 Pass Fish: Site ID Date Drainage Area (mi2) Ecoregion Major Drainage Riffle Stream? FIBI score FIBI Class 47b FIBI BIT FIBI Pass/Fail 63 8/4/20 333.4 47b MO Yes 51 Good 53 Fail 63 8/12/14 333.4 47b MO Yes 41 Fair 53 Fail Overall: Community Assessment Type Assessment Result Support Level IR Category Reason Benthic
Macroinvertebrates Monitored Pass (2/2) Full
Fish Evaluated Fail (0/2) Not Assessment
was evaluated because samples greater than five years old Overall Evaluated Fail Not 5bt were
used to complete the (FIBI) assessment.
Class BWW1 - Biological Sampling:
Benthic Macroinvertebrates:
Class HH – No Data
Assessment Key Dates
8/12/2014 | Biological Monitoring |
8/4/2020 | 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 |
380 | Quantitative physical habitat assessment |
420 | Indicator bacteria monitoring |