Cedar River IA 02-CED-479
from Rock Cr. nr Orchard (S24 T97N R17W Floyd Co.) to Iowa / Minnesota state line (S8 T100N R18W Mitchell 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 8:12:25 AM
- Updated
- 2/2/2024 2:34:09 PM
The Class A1 use was assessed as "not supported" based on levels of indicator bacteria (E. coli) that exceeded Class A1 criteria. The Class BWW1 use was assessed as "fully supported" based on water quality monitoring data. The Class HH use was assessed as "not supported" based on the existence of a historic one meal per week mercury consumption advisory for any predator fish in this segment. Note: A TMDL for indicator bacteria was approved by EPA in February 2010 for this segment. The approval of this TMDL moved the bacterial impairment for this segment from Iowa's list of Section 303(d) waters (Category 5a of the IR) to IR Category 4a (impaired; TMDL not required).
Data Sources: Data Source Data Source ID Data Type Data Age Site ID Site Name Site Description MNPCA 15 WQ CY 2018-2020 99990099 Cedar River 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 99990099 15 0/9/6 NA 255 184 YES NA 4 / 3 2 / NA YES Monitored 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 99990099 15 30 / 3 6.17 8.32 7.79 1 6 NO Monitored 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 99990099 15 Dissolved Oxygen 30 / 3 7.3 12.5 8.9 0 NA / NA 6 NO Monitored Full 99990099 15 pH 30 / 3 6.17 8.32 7.79 1 NA / NA 6 NO Monitored Full 99990099 15 Temperature 30 / 3 2.6 24.6 17.9 0 NA / NA 6 NO Monitored Full
Class A1 - Indicator Bacteria:
Class A1 – pH:
Class BWW1 - Binomial Parameters:
Class HH - Fish Tissue Sampling: A historic one meal/week mercury consumption advisory for any predator fish exists on this segment. Based on IR Methodology, the Class HH (fish consumption) use was assessed as “not supported.”