Wolf Creek IA 02-CED-530
mouth (S29 T87N R11W Black Hawk Co.) to confluence with Twelvemile Cr. in S19 T86N R13W Tama 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
- Unknown
- Created
- 8/31/2020 12:09:03 PM
- Updated
- 10/16/2020 8:51:33 AM
Assessment Summary
The presumptive Class A1 use was assessed as "partially supported" due to levels of indicator bacteria (E. coli) that violated state water quality criteria. The Class BWW1 use was assessed as "fully supported" based on ambient water quality monitoring data and also on biological sampling data. The Class HH use was assessed as "fully supported" based on ambient 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 2016-2018 10070002 Wolf Creek at La Porte City Iowa DNR 6 BIO See Below 1154 Wolf Creek La Porte City - Main Street Bridge Class A1 -
Indicator Bacteria: Site ID Data Source ID # Samples / # Years 2016 Geometric Mean 2017 Geometric Mean 2018 Geometric Mean Annual Geometric Mean Violation # Violations % Violations Significantly >10% Violations Assessment Type Support Level 10070002 6 20 / 3 458.96 580.54 491.6 Yes 15 75% Yes Monitored Partial Class A - pH: Site ID Data Source ID # Samples / # Years Maximum Value Mean Value Median Value # Violations % Violations Significantly >10% Violations Assessment Type Support Level 10070002 6 36 / 3 8.4 8.1 8.2 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 10070002 6 Ammonia 36 / 3 0.16 0.04 0.02 0 / 0 0% / 0% No Monitored Full 10070002 6 Chloride 36 / 3 24 20 20 0 / 0 0% / 0% No Monitored Full 10070002 6 Dissolved oxygen 36 / 3 14.4 10.4 10.4 NA / 0 NA / 0% No Monitored Full 10070002 6 pH 36 / 3 8.4 8.1 8.2 0 / NA 0% / NA No Monitored Full 10070002 6 Sulfate 36 / 3 51 22 20 0 / NA 0% / NA No Monitored Full 10070002 6 Temperature 36 / 3 25.5 11.6 12 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 10070002 6 Aluminum 9 / 2 4.1 1.673 1.4 0 / 0 0% / 0% No Evaluated Full 10070002 6 Arsenic 9 / 2 1.2 0.83 0.89 0 / 0 0% / 0% No Evaluated Full 10070002 6 Cadmium 9 / 2 0.025 0.025 0.025 0 / 0 0% / 0% No Evaluated Full 10070002 6 Chromium 9 / 2 1.2 0.82 0.94 0 / 0 0% / 0% No Evaluated Full 10070002 6 Copper 9 / 2 0.88 0.52 0.48 0 / 0 0% / 0% No Evaluated Full 10070002 6 Lead 9 / 2 0.25 0.07 0.05 0 / 0 0% / 0% No Evaluated Full 10070002 6 Nickel 9 / 2 2.4 2 2 0 / 0 0% / 0% No Evaluated Full 10070002 6 Selenium 9 / 2 2.3 1.8 1.7 0 / 0 0% / 0% No Evaluated Full 10070002 6 Zinc 9 / 2 3.4 1.51 0.98 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 47c BMIBI BIT BMIBI Pass/ Fail 1154 8/15/18 326 47c MS/WW Floating ArtSub 81 Excellent 52 Pass
Overall Assessment: Community Assessment Type Assessment Result Support Level Earned IR Category Actual IR Category Reason Benthic
Macroinvertebrates Evaluated Pass (1/1) Full 1 1 Assessment is evaluated because it was
based on a single sample. 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 10070002 6 Cadmium 9 / 2 0.025 0.025 0.025 9 No All Non-Detect Full 10070002 6 Chromium 9 / 2 1.2 0.82 0.94 0 No Evaluated Full 10070002 6 Copper 9 / 2 0.88 0.52 0.48 0 No Evaluated Full 10070002 6 Nickel 9 / 2 2.4 2 2 0 No Evaluated Full 10070002 6 Selenium 9 / 2 2.3 1.8 1.7 0 No Evaluated Full 10070002 6 Zinc 9 / 2 3.4 1.51 0.98 0 No Evaluated Full
Assessment Key Dates
8/15/2018 | Biological Monitoring |
1/7/2016 | Fixed Monitoring Start Date |
12/11/2018 | 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 |