Wapsipinicon River IA 01-WPS-343
from Harter Cr. at Independence (NW 1/4 S34 T89N R9W Buchanan Co.) to confluence with Little Wapsipinicon R. near Littleton in S9 T89N R10W Buchanan Co.
- Cycle
- 2026
- Current Phase
- Public Comment
- Overall IR
- 5 - Water is impaired or threatened and a TMDL is needed.
- Trend
- Stable
- Created
- 10/27/2025 3:08:50 PM
- Updated
- 1/12/2026 8:23:11 AM
The Class A1 use was assessed as “not supported” based on levels of indicator bacteria (E. coli) that violated state water quality criteria. The Class BWW1 use was assessed as "WINOFI" based on the occurrence of a single fish kill in this segment. The Class HH (fish consumption) use was assessed as “not supported” based on fish tissue monitoring data and on the historical existence of a one meal/week mercury consumption advisory on this segment.
Data Sources: Data Source Data Source ID Data Type Data Age Site ID Site
Name Site
Description Iowa DNR 6 WQ CY 2022-2024 10100001 Wapsipinicon
River near Otterville
Iowa DNR 6 BIO See Below 949 Wapsipinicon
River Otterville Iowa DNR 6 FT See Below 1366 Wapsipinicon
River Otterville
Bridge Iowa DNR 6 FT See Below 1379 Wapsipinicon
River Otterville
WMA Boat Ramp Site ID Data Source ID # Samples per Year (2022/ 2023/2024) 2022 Geometric Mean 2023 Geometric Mean 2024 Geometric Mean Violates Annual Geometric Mean? # 2022 SSM violations / SSM Violations needed for impairment # 2023 SSM violations / SSM Violations needed for impairment # 2024 SSM violations / SSM Violations needed for impairment Violates Annual SSM Significantly >10% Rule? Assessment Type Support Level 10100001 6 8/8/8 243 193 143 YES 3 / 3 3 / 3 2 / 3 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 10100001 6 35 / 3 7.4 8.8 8.1 0 7 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 10100001 6 Chloride 36 / 3 14 36 24 NA 0 / 0 7 NO MONITORED FULL 10100001 6 Dissolved Oxygen 35 / 3 7.5 15.5 11.3 0 NA / NA 7 NO MONITORED FULL 10100001 6 pH 35 / 3 7.4 8.8 8.1 0 NA / NA 7 NO MONITORED FULL 10100001 6 Sulfate 36 / 3 12 35 22 0 NA / NA 7 NO MONITORED FULL 10100001 6 Temperature 36 / 3 0.1 27.1 12.3 0 NA / NA 7 NO MONITORED 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 10100001 6 Aluminum 18 / 2 2200 398 260 0 / 1 NO MONITORED FULL 10100001 6 Ammonia 35 / 3 0.68 0.05 0.02 0 / 0 NO MONITORED FULL 10100001 6 Cadmium 18 / 2 0.5 0.5 0.5 0 / 0 NO MONITORED FULL 10100001 6 Chromium 18 / 2 1 0.65 0.55 0 / 0 NO MONITORED FULL 10100001 6 Copper 18 / 2 1.9 0.7 0.5 0 / 0 NO MONITORED FULL 10100001 6 Lead 18 / 2 1 1 1 0 / 0 NO MONITORED FULL 10100001 6 Nickel 18 / 2 1.5 1 0.9 0 / 0 NO MONITORED FULL 10100001 6 Selenium 36 / 3 1.2 0.6 0.5 0 / 0 NO MONITORED FULL 10100001 6 Silver 18 / 2 1 1 1 0 / 0 NO MONITORED FULL 10100001 6 Zinc 18 / 2 2.5 0.6 0.5 0 / 0 NO MONITORED FULL BioNet Site ID Date Drainage Area (mi2) Ecoregion Major Drainage BM Sample Gear BMIBI score BMIBI Class 47c BMIBI BIT BMIBI Pass/Fail 949 8/26/21 909 47c MS Art Sub 65 Good 52 Pass Community Assessment Type Assessment Result Support Level IR Category Reason Benthic Macroinvertebrate Evaluated Pass (1/1) Full Assessment was evaluated because the drainage area of the
sample site was Overall Evaluated Pass Full 1 greater than the calibrated range. The Class BWW1 aquatic life use assessment based on the 2021 fish kill
placed this segment in Category 3b. This assessment was “evaluated” because
there was a single fish kill on this segment in the last five years. Segments
assessed using “evaluated” assessments are placed in Category 3b and are added
to the state list of Waters In Need Of Further Investigation (WINOFI). If no
additional fish kills are reported in this segment for a 5-year period (2022-2026),
the Category will be changed from 3b to 3a (not assessed). Details about the 2021 fish kill can be found here: https://programs.iowadnr.gov/fishkill/Events/1015 Site ID Biopart Year Species # in sample / # of
samples Avg Length (cm) (Avg) Hg (ppm) Chlordane (ppm) Sum PCBs (ppm) 1379 tissue plug 2021 smallmouth bass 20 26.6 0.113 1366 tissue plug 2020 northern pike 10 69 0.294 1366 tissue plug 2020 walleye 1 49.8 0.4 1366 tissue plug 2019 walleye 9 48.5 0.384 Support Level Not A historic one meal/week mercury consumption advisory existed
on this segment. Based on IR Methodology, the Class HH (fish consumption) use
was assessed as “not supported.” 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 10100001 6 Copper 18 / 2 1.9 0.7 0.5 15 NO MONITORED FULL Site ID Data Source ID Parameter Name # Samples per Year (2022/ 2023/2024) 2022 Mean 2023 Mean 2024 Mean # Non-Detects per Year (2022/ 2023/2024) Support Level per Year (2022/ 2023/2024) Assessment Type Support Level 10100001 6 Selenium 12/12/12 0.542 0.5 0.608 11/12/10 FS/FS/FS MONITORED FULL
Class A1 - Indicator Bacteria:
Class A1 – pH:
Class BWW1 - Binomial Parameters:
Class BWW1 - Toxic Parameters:
Class BWW1 - Biological Sampling:
Benthic Macroinvertebrates:
Overall:
Class BWW1 – Fish kill Assessment:
Class HH - Fish Tissue Sampling:
Class HH-F - Toxic Parameters: