Cedar River IA 02-CED-449
mouth (S20 T75N R4W Louisa Co.) to confluence with Sugar Cr. in S17 T78N R2W Muscatine 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
- Unknown
- Created
- 11/1/2023 8:12:43 AM
- Updated
- 1/17/2024 7:35:56 AM
Assessment Summary
The 2020-2022 E. coli data suggest full support of the Class A1 use; however, delisting an impairment requires a monitored assessment. Therefore, the Category 5a Class A1 impairment will remain. The Class BWW1 use was assessed as "WINOFI” based on biological sampling data. The Class HH use was assessed as “fully supported” based on water quality monitoring data. Note: This segment was not included in the 2010 EPA TMDL for indicator bacteria impairments in nine segments of Cedar River.
Assessment Explanation
Data Sources: Data Source Data Source ID Data Type Data Age Site ID Site
Name Site
Description Iowa DNR 6 WQ CY 2020-2022 10700001 Cedar
River near Conesville
Iowa DNR 6 BIO See Below 849 Cedar
River Conesville 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 10700001 6 8/8/8 59 68 85 NO 1 / 3 1 / 3 2 / 3 NA Eval Full The 2020-2022 E. coli data suggest full support of the Class A1 use; however, delisting an impairment requires a monitored assessment. Therefore, the Category 5a Class A1 impairment will remain. Class A1 - 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 10700001 6 36 / 3 7.9 9.3 8.5 2 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 10700001 6 Chloride 36 / 3 17 55 34 NA 0 / 0 7 NO Mon Full 10700001 6 Dissolved Oxygen 36 / 3 7.1 14.7 11.7 0 NA / NA 7 NO Mon Full 10700001 6 pH 36 / 3 7.9 9.3 8.5 2 NA / NA 7 NO Mon Full 10700001 6 Sulfate 36 / 3 15 47 31 0 NA / NA 7 NO Mon Full 10700001 6 Temperature 36 / 3 0.1 29.1 12.8 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 10700001 6 Ammonia 36 / 3 0.65 0.12 0.02 0 / 0 NO Mon Full 10700001 6 Cadmium 20 / 3 0.5 0.5 0.5 0 / 0 NO Mon Full 10700001 6 Chromium 20 / 3 4 0.8 0.55 0 / 0 NO Mon Full 10700001 6 Lead 20 / 3 1 0.9 1 0 / 0 NO Mon Full 10700001 6 Nickel 20 / 3 2.4 1.4 1.2 0 / 0 NO Mon Full 10700001 6 Selenium 18 / 2 2 1 1 0 / 0 NO Mon Full 10700001 6 Silver 20 / 3 1 0.902 1 0 / 0 NO Mon Full 10700001 6 Zinc 20 / 3 6.7 1.6 1.1 0 / 0 NO Mon Full BioNet Site ID Date Drainage Area (mi2) Ecoregion Major Drainage BM Sample Gear BMIBI score BMIBI Class 72d BMIBI BIT BMIBI Pass/Fail 849 9/13/22 7788.9 72d MS Floating Art Sub 36 Fair 51 Fail 849 8/27/18 7788.9 72d MS Floating Art Sub 35 Fair 51 Fail Community Assessment Type Assessment Result Support Level IR Category Reason Benthic
Macroinvertebrates Evaluated Fail (0/2) WINOFI Assessment was evaluated because the
drainage area of the sample site Overall Evaluated Fail WINOFI 3bu was greater than the calibrated range. 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 10700001 6 Selenium 18 / 2 2 1 1 6 NO Mon Full
Class A1 - Indicator Bacteria:
Class BWW1 - Binomial Parameters:
Class BWW1 - Toxic Parameters:
Class BWW1 - Biological Sampling:
Benthic Macroinvertebrates:
Overall:
Class
HH-F - Toxic Parameters:
Assessment Key Dates
8/27/2018 | Biological Monitoring |
1/8/2020 | Monitoring Start |
12/7/2022 | Monitoring End |
9/13/2022 | Biological Monitoring |
Methods
200 | Physical/Chemical Monitoring |
315 | Regional reference site approach |
320 | Benthic macroinvertebrate surveys |
420 | Indicator bacteria monitoring |