Little Volga River IA 01-VOL-328
mouth (north line of S2 T92N R9W Fayette Co.) to Hwy 150 bridge crossing at Maynard at south line of S14 T92N R9W Fayette Co.
- Cycle
- 2020
- Release Status
- Final
- Overall IR
- 5 - Water is impaired or threatened and a TMDL is needed.
- Trend
- Unknown
- Created
- 6/15/2020 8:40:32 AM
- Updated
- 10/14/2020 11:06:28 AM
The presumptive Class A1 use remains assessed as “not supported” due to violations of Iowa water quality criteria for indicator bacteria (E. coli). The Class BWW1 use was assessed as “partially supported” based on a fish kill investigation. The Class HH use remains assessed as “partially supported” due to the existence of a one meal per week consumption advisory for smallmouth bass in this segment.
Sources of
Data: Data Source Data Source ID Data Type Data Age Site ID BioNet Site ID Site Name Site Description Iowa DNR 6 WQ CY 2012-2014 15330008 Little Volga R @ Neon Road Presumptive Class
A1 - Indicator Bacteria: Historical 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 15330008 6 23 / 3 2069 784 399 Yes 20 87% Yes Evaluated Not Class BWW1 -
Conventional Parameters: Historical 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 15330008 6 Ammonia 13 / 2 0.2 0.07 0.05 0 / 0 0%
/ 0% No Evaluated Full 15330008 6 Chloride 19 / 3 39 31.5 30 0 / 0 0%
/ 0% No Evaluated Full 15330008 6 Dissolved oxygen 23 / 3 12 8.4 8 NA / 0 NA /
0% No Evaluated Full 15330008 6 pH 23 / 3 8.6 8.1 8.1 0 / NA 0%
/ NA No Evaluated Full 15330008 6 Temperature 22 / 3 26.1 14.5 14.05 0 / 0 0%
/ 0% No Evaluated Full
Class BWW1 -
Fish Kill: The Class BWW1 use assessment based on the 2017 fish kill placed this segment in Category 4d. The fish kill was caused by a “pollutant” or was suspected to be caused by a “pollutant”; therefore, the Class BWW1 use was considered impaired. However, because restitution for the fish killed was received, the Class BWW1 use was placed in Category 4d (impaired but TMDL not required). DNR feels that (1) TMDLs should not be required for a fish kill caused by a one-time illegal or unauthorized release of a pollutant where enforcement action was taken and (2) enforcement action is more appropriate and effective for addressing a spill-related impairment than the TMDL process. Details about the 2017 fish kill can be found here:https://programs.iowadnr.gov/fishkill/Events/936 Class HH - Consumption Advisory: This segment is included in the Volga River fish tissue consumption advisory – see https://www.iowadnr.gov/Environmental-Protection/Water-Quality/Water-Monitoring/Fish-Tissue. This advisory recommends consumption of no more than one meal per week of smallmouth bass from this river segment. This advisory extends from the town of Volga upriver to the headwaters of the Volga River near Hawkeye in Fayette County and includes the Little Volga River and North Branch Volga River. The existence of a one-meal-per-week consumption advisory indicates that the Class HH use should be assessed as “partially supported.”