North Raccoon River IA 04-RAC-1139
from County Road M54 (S24T88N R36W Sac Co.) to confluence with Drainage Ditch 101 in S36 T91N R36W Buena Vista Co.
- Cycle
- 2020
- Release Status
- Final
- Overall IR
- 5 - Water is impaired or threatened and a TMDL is needed.
- Trend
- Unknown
- Created
- 9/14/2020 9:02:10 AM
- Updated
- 10/13/2020 6:47:12 AM
The Class A1 use remains 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 "partially supported” based on biological sampling data. All other designated uses were "not assessed". Note: A TMDL for pathogen indicator impairments in the Raccoon River basin was approved by EPA in 2008. Because this TMDL covers bacterial impairments, this impairment was moved from IR Category 5a from the 2008 assessment/listing cycle to IR Category 4a (impaired; TMDL approved) for the 2010 cycle and remains there for this cycle. S
Sources
of Data: Data Source Data Source ID Data Type Data Age Site ID Site Name Site Description Iowa DNR 6 WQ CY 2014-2016 10810002 North Raccoon River US of Sac City (US1) Iowa DNR 6 BIO See Below 143 North Raccoon River Raccoon River Greenbelt – Sac City Iowa DNR 6 BIO See Below 1157 North Raccoon River Sac City – REMAP #443 Class
A1 - Indicator Bacteria: Site ID Data Source ID # Samples / # Years 2012 Geometric Mean 2013 Geometric Mean 2014 Geometric Mean Annual Geometric Mean Violation # Violations % Violations Significantly >10% Violations Assessment Type Support Level 10810002 6 22 / 3 70 148 274 Yes 9 41% Yes Evaluated 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 10810002 6 33 / 3 9 8.26 8.3 0 0% No Evaluated 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 10810002 6 Ammonia 33 / 3 1.7 0.18 0.05 0 / 0 0% / 0% No Evaluated Full 10810002 6 Chloride 33 / 3 140 63 63 0 / 0 0% / 0% No Evaluated Full 10810002 6 Dissolved oxygen 33 / 3 17.3 10.7 10.2 NA / 0 NA / 0% No Evaluated Full 10810002 6 pH 33 / 3 9 8.26 8.3 0 / NA 0% / NA No Evaluated Full 10810002 6 Sulfate 33 / 3 410 173 170 0 / NA 0% / NA No Evaluated Full 10810002 6 Temperature 33 / 3 29.5 11.3 9.8 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 47b BMIBI BIT BMIBI Pass/ Fail 1157 9/18/17 330 47b MS/WW Hess 54 Fair 62 Fail 143 8/13/15 328 47b MS/WW Hess 62 Good 62 Pass 143 7/31/12 328 47b MS/WW Hess 57 Good 62 Fail Fish: BioNet Site ID Date Drainage Area (mi2) Ecoregion Major Drainage/Thermal Riffle Stream? FIBI score FIBI Class 47b FIBI BIT FIBI Pass/ Fail 1157 9/18/17 330 47b MS/WW No 72 Excellent 32 Pass 143 8/13/15 328 47b MS/WW Yes 62 Good 53 Pass Overall: Community Assessment Type Assessment Result Support Level Earned IR Category Actual IR Category Reason Benthic
Macroinvertebrates Evaluated Fail (1/3) Partial Fish Monitored Pass (2/2) Full Overall Evaluated Fail Partial 3bc 5bt Assessment
is evaluated because it included samples not collected in the last five
years.