West Fork Little Sioux River IA 06-LSR-1598
mouth (S12 T84N R45W Monona Co.) to confluence with a small unnamed tributary near Climbing Hill in S16 T87N R45W Woodbury Co.
- Assessment Cycle
- 2024
- Release Status
- Pending
- Data Collection Period
- Overall IR Category
- 5 - Water is impaired or threatened and a TMDL is needed.
- Trend
- Stable
- Created
- 11/1/2023 8:13:04 AM
- Updated
- 2/1/2024 6:56:21 AM
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 BWW2 use was assessed as "not supported" based on violations of the state water quality chronic criteria for selenium and "WINOFI" based on biological sampling data.
Data Sources: Data Source Data Source ID Data Type Data Age Site ID Site
Name Site
Description Iowa DNR 6 WQ CY 2020-2022 10970002 West
Fork Ditch at Hornick
Iowa DNR 6 BIO See Below 934 West
Fork Little Sioux River Hornick Site ID Data Source ID # Samples per Year (2020/ 2021/2022) 2020 Geometric Mean 2021 Geometric Mean 2022 Geometric Mean Violates Annual Geometric Mean? # 2020 SSM violations / SSM Violations needed for impairment # 2021 SSM violations / SSM Violations needed for impairment # 2022 SSM violations / SSM Violations needed for impairment Violates Annual SSM Significantly >10% Rule? Assessment Type Support Level 10970002 6 8/8/8 227 192 95 YES 3 / 3 5 / 3 2 / 3 YES Mon Not 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 10970002 6 36 / 3 7.4 8.6 8.1 0 7 NO Mon Full 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 10970002 6 Chloride 36 / 3 16 36 19 NA 0 / 0 7 NO Mon Full 10970002 6 Dissolved Oxygen 36 / 3 7.6 15.9 10.9 0 NA / NA 7 NO Mon Full 10970002 6 pH 36 / 3 7.4 8.6 8.1 0 NA / NA 7 NO Mon Full 10970002 6 Sulfate 36 / 3 51 120 78 0 NA / NA 7 NO Mon Full 10970002 6 Temperature 36 / 3 0 27.1 12.4 0 NA / NA 7 NO Mon Full 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 10970002 6 Ammonia 36 / 3 0.73 0.05 0.02 0 / 0 NO Mon Full 10970002 6 Cadmium 20 / 3 0.5 0.5 0.5 0 / 0 NO Mon Full 10970002 6 Chromium 20 / 3 2 0.82 0.7 0 / 0 NO Mon Full 10970002 6 Lead 20 / 3 1 0.93 1 0 / 0 NO Mon Full 10970002 6 Nickel 20 / 3 3.1 1.7 1.4 0 / 0 NO Mon Full 10970002 6 Selenium 18 / 2 8 6 6 0 / 9 YES Mon Not 10970002 6 Silver 20 / 3 1 0.902 1 0 / 0 NO Mon Full 10970002 6 Zinc 20 / 3 3.3 0.9 0.5 0 / 0 NO Mon Full Site ID Date Drainage Area (mi2) Ecoregion Major Drainage BM Sample Gear BMIBI score BMIBI Class 47a BMIBI BIT BMIBI Pass/Fail 934 8/13/19 399 47d MO Floating Art Sub 40 Fair 54 Fail Community Assessment Type Assessment Result Support Level IR Category Reason Benthic
Macroinvertebrates Evaluated Fail (0/1) WINOFI Overall Evaluated Fail WINOFI 3bc Assessment was
evaluated because it was based on a single sample.
Class A1 - Indicator Bacteria:
Class A1 – pH:
Class BWW2 - Binomial Parameters:
Class BWW2 - Toxic Parameters:
Class BWW2 - Biological Sampling:
Benthic Macroinvertebrates:
Overall: