Floyd River IA 06-FLO-1552
mouth to West Branch Floyd R. in S2 T91N R46W Plymouth 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 8:54:21 AM
- Updated
- 10/13/2020 2:31:36 PM
Assessment Summary
The Class A1 use remains 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 "partially supported" based on biological sampling data and assessed as "not supported" on violations of the chronic water quality criteria for selenium. 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 2014-2016, CY 2016-2018 10750001 Floyd River near Sioux City Iowa DNR 6 BIO See Below 184 Floyd River James 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 10430001 6 24 / 3 236 245 1287 Yes 15 62% Yes Evaluated Not 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 10750001 6 34 / 3 8.6 8.2 8.3 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 10750001 6 Ammonia 34 / 3 1.4 0.09 0.02 0 / 0 0% / 0% No Monitored Full 10750001 6 Chloride 36 / 3 98 45 42 0 / 0 0% / 0% No Monitored Full 10750001 6 Dissolved oxygen 36 / 3 14 10.4 10.6 NA / 0 NA / 0% No Monitored Full 10750001 6 pH 34 / 3 8.6 8.2 8.3 0 / NA 0% / NA No Monitored Full 10750001 6 Sulfate 36 / 3 140 99 97 0 / NA 0% / NA No Monitored Full 10750001 6 Temperature 36 / 3 29 12 11 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 10750001 6 Aluminum 9 / 2 21 5.47 2.6 0 / 0 0% / 0% No Evaluated Full 10750001 6 Arsenic 9 / 2 3.2 2.5 2.7 0 / 0 0% / 0% No Evaluated Full 10750001 6 Cadmium 9 / 2 0.07 0.03 0.025 0 / 0 0% / 0% No Evaluated Full 10750001 6 Chromium 9 / 2 1.5 0.79 0.84 0 / 0 0% / 0% No Evaluated Full 10750001 6 Copper 9 / 2 5.4 1.71 1.2 0 / 0 0% / 0% No Evaluated Full 10750001 6 Lead 9 / 2 0.34 0.116 0.11 0 / 0 0% / 0% No Evaluated Full 10750001 6 Nickel 9 / 2 5.8 3.1 2.9 0 / 0 0% / 0% No Evaluated Full 10750001 6 Selenium 9 / 2 17 9.2 8.1 0 / 7 0% / 78% Yes Evaluated Not 10750001 6 Zinc 9 / 2 3.3 1.8 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 47e BMIBI BIT BMIBI Pass/ Fail 184 8/30/16 886 47e MO/WW Float ArtSub 45 Fair 54 Fail 184 9/10/15 886 47e MO/WW Float ArtSub 28 Poor 54 Fail 184 8/6/15 886 47e MO/WW ArtSub 53 Fair 54 Fail 184 10/7/14 886 47e MO/WW ArtSub 35 Fair 54 Fail Overall: Community Assessment Type Assessment Result Support Level Earned IR Category Actual IR Category Reason Benthic
Macroinvertebrates Evaluated Fail (0/4) Partial 3bu 3bu 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 10750001 6 Cadmium 9 / 2 0.07 0.03 0.025 8 No Evaluated Full 10750001 6 Chromium 9 / 2 1.5 0.79 0.84 0 No Evaluated Full 10750001 6 Copper 9 / 2 5.4 1.71 1.2 0 No Evaluated Full 10750001 6 Nickel 9 / 2 5.8 3.1 2.9 0 No Evaluated Full 10750001 6 Selenium 9 / 2 17 9.2 8.1 0 No Evaluated Full 10750001 6 Zinc 9 / 2 3.3 1.8 1.5 0 No Evaluated Full
Assessment Key Dates
1/8/2014 | Fixed Monitoring Start Date |
12/7/2016 | Fixed Monitoring End Date |
10/7/2014 | Biological Monitoring |
8/6/2015 | Biological Monitoring |
9/10/2015 | Biological Monitoring |
8/30/2016 | Biological Monitoring |
1/5/2016 | Fixed Monitoring Start Date |
12/5/2018 | Fixed Monitoring End Date |
Methods
230 | Fixed station physical/chemical (conventional plus toxic pollutants) |
315 | Regional reference site approach |
320 | Benthic macroinvertebrate surveys |
420 | Indicator bacteria monitoring |