Jackson Creek IA 05-CHA-1332
mouth (S1 T70N R21W Wayne Co.) to confluence with unnamed tributary in S12 T68N R21W Wayne Co.
- Cycle
- 2020
- Release Status
- Final
- Overall IR
- 5 - Water is impaired or threatened and a TMDL is needed.
- Trend
- Unknown
- Created
- 9/30/2020 11:43:03 AM
- Updated
- 10/12/2020 12:58:52 PM
The presumptive Class A1 use remains assessed as "partially supported" due to levels of indicator bacteria (E. coli) that exceeded state water quality criteria. The Class BWW2 use remains assessed as “partially supported” based on historic biological sampling data; the latest biological sample indicated full support but DNR IR methodology requires two samples to de-list an impairment.
Data
Sources: Data Source Data Source ID Data Type Data Age Site ID Site Name Site Description USACE 12 WQ CY 2010-2014 15930006 Jackson Creek at Liberty (Site RA-39) Iowa DNR 6 BIO See Below 857 Jackson Creek Corydon Presumptive
Class A1 - Indicator Bacteria: 2010-2012 Site ID Data Source ID # Samples / # Years 2010 Geometric Mean 2011 Geometric Mean 2012 Geometric Mean Annual Geometric Mean Violation # Violations % Violations Significantly >10% Violations Assessment Type Support Level 15930006 12 18 / 3 836 248 934 Yes 10 62% Yes Evaluated Partial Presumptive
Class A1 - pH: 2012-2014 Site ID Data Source ID # Samples / # Years Maximum Value Mean Value Median Value # Violations % Violations Significantly >10% Violations Assessment Type Support Level 15930006 12 59 / 3 8 7.4 7.6 0 0% No Evaluated Full Class
BWW2 - Conventional Parameters: 2012-2014 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 15930006 12 Ammonia 30 / 3 1.7 0.14 0.05 0 / 0 0% / 0% No Evaluated Full 15930006 12 Chloride 41 / 3 99 18 12 0 / 0 0% / 0% No Evaluated Full 15930006 12 Dissolved oxygen 59 / 3 12.9 8.3 8.1 NA / 2 NA / 3% No Evaluated Full 15930006 12 pH 59 / 3 8 7.4 7.6 0 / NA 0% / NA No Evaluated Full 15930006 12 Temperature 59 / 3 25.6 16.5 17.5 0 / 0 0% / 0% No Evaluated Full Class BWW2 - Biological
Sampling: Benthic
Macroinvertebrates: BioNet Site ID Date Drainage Area (mi2) Ecoregion Major Drainage/ Thermal BM Sample Gear BMIBI score BMIBI Class 40a BMIBI BIT BMIBI Pass/ Fail 857 9/14/11 53 40a MO/WW ArtSub 40 Fair 41 Pass Fish: BioNet Site ID Date Drainage Area (mi2) Ecoregion Major Drainage/ Thermal Riffle Stream? FIBI score FIBI Class 40a FIBI BIT FIBI Pass/ Fail 857 9/14/11 53 40a MO/WW NA 31 Fair 33 Pass Overall: Community Assessment Type Assessment Result Support Level Earned IR Category Actual IR Category Reason Benthic
Macroinvertebrates Evaluated Pass (1/1) Full BMIBI
score passed when the 8 point UAV was applied to a single sample. Fish Evaluated Pass (1/1) Full FIBI
score passed when the 7 point UAV was applied to a single sample. Overall Evaluated Pass Full 1 5bt Assessment
was evaluated because it was based on an old single sample. DNR
now requires a segment have two or more biological samples collected from the
segment in multiple years in a recent five year period to be considered
“monitored”. According to DNR’s IR methodology, impairments based on
“evaluated” assessments are of lesser confidence and are thus not appropriate
for Section 303(d) listing (Category 5 of the Integrated Report). DNR does,
however, consider these impairments as appropriate for listing under either
Category 2b or 3b of the Integrated Report (waters potentially impaired and
in need of further investigation). However, despite this change in assessment
methodology and type, this waterbody remains in IR Category 5bt and remains
on Iowa’s Section 303(d) list of impaired waters.