Boyer River IA 06-BOY-1502
from confluence with Willow Cr. (S28 T78N R44W Harrison Co.) to the Harrison-Crawford county line.
- 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
- 12/27/2021 3:05:45 PM
- Updated
- 12/27/2021 3:08:19 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 "not supported" based on water quality monitoring data (violations of the chronic selenium criteria). 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 2014-2016, CY 2018-2020 10430001 Boyer River near Missouri Valley
Iowa DNR 6 BIO See Below 912 Boyer River Missouri Valley Site ID Data Source ID # Samples / # Years 2014 Geo. Mean 2015 Geo. Mean 2016 Geo. Mean Annual Geometric Mean Violation # Violations % Violations Significantly >10% Violations Assessment Type Support Level 10430001 6 24 / 3 487 1138 539 Yes 18 75% Yes Evaluated Not 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 10430001 6 0/0/6 NA NA 242 YES NA NA 3 / NA NA Evaluated 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 10430001 6 36 / 3 7.1 8.5 8 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 10430001 6 Ammonia 36 / 3 0.025 1.6 0.1 NA 0 / 0 7 NO Monitored Full 10430001 6 Chloride 36 / 3 13 110 20 NA 0 / 0 7 NO Monitored Full 10430001 6 Dissolved Oxygen 36 / 3 7.3 14.3 10.1 0 NA / NA 7 NO Monitored Full 10430001 6 pH 36 / 3 7.1 8.5 8 0 NA / NA 7 NO Monitored Full 10430001 6 Sulfate 36 / 3 23 55 35 0 NA / NA 7 NO Monitored Full 10430001 6 Temperature 36 / 3 0 25.5 11.1 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 10430001 6 Aluminum 14 / 3 19 5.41 2.95 0 / 0 NO Monitored Full 10430001 6 Arsenic 13 / 3 5.8 2.9 2.4 0 / 0 NO Monitored Full 10430001 6 Cadmium 13 / 3 0.2 0.0431 0.025 0 / 0 NO Monitored Full 10430001 6 Chromium 13 / 3 1.9 1 1 0 / 0 NO Monitored Full 10430001 6 Lead 13 / 3 4.9 0.5 0.1 0 / 0 NO Monitored Full 10430001 6 Nickel 13 / 3 8 4 3.7 0 / 0 NO Monitored Full 10430001 6 Selenium 13 / 3 11 6.6 6.2 0 / 11 YES Monitored Not 10430001 6 Silver 13 / 3 0.025 0.025 0.025 0 / 0 NO Monitored Full 10430001 6 Zinc 13 / 3 13 3.59 2.4 0 / 0 NO Monitored Full Site ID Date Drainage Area (mi2) Ecoregion Major Drainage BM Sample Gear BMIBI score BMIBI Class 47m BMIBI BIT BMIBI Pass/Fail 912 8/13/18 928 47m MO Floating Art Sub 56 Good 54 Pass Overall: Community Assessment Type Assessment Result Support Level IR Category Reason Benthic
Macroinvertebrates Evaluated Pass (1/1) Full Assessment was evaluated
because the drainage area of the site is Overall Evaluated Pass Full 1 greater than the
calibrated range.
Class A1 - Indicator Bacteria: 2014-2016
Class A1 - Indicator Bacteria: 2018-2020
Class BWW1 - Biological Sampling:
Benthic Macroinvertebrates:
Class HH - No Data
Assessment Key Dates
1/9/2018 | Fixed Monitoring Start Date |
12/2/2020 | Fixed Monitoring End Date |
8/13/2018 | Biological Monitoring |
1/7/2014 | Fixed Monitoring Start Date |
12/7/2016 | 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 |