North Branch Volga River IA 01-VOL-330
mouth (S33 T93N R9W Fayette Co.) to confluence with unnamed tributary in S8 T93N R9W Fayette Co.
- Cycle
- 2020
- Release Status
- Final
- Overall IR
- 5 - Water is impaired or threatened and a TMDL is needed.
- Trend
- Unknown
- Created
- 8/25/2020 10:39:53 AM
- Updated
- 10/14/2020 11:02:07 AM
The presumptive Class A1 use remains assessed as “partially supported” due to violations of Iowa water quality criteria for indicator bacteria (E. coli). The Class BWW2 use was assessed as "fully supported" based on biological sampling data and water quality monitoring data. The Class HH use remains assessed as “partially supported" due to existence of a one meal/week mercury consumption advisory for smallmouth bass in this segment.
Sources
of Data: Data Source Data Source ID Data Type Data Age Site ID Site
Name Site
Description Iowa DNR 6 WQ CY2012-2014 15330014 Volga
River, North Branch at HWY 93 VRN-10 Iowa DNR 6 BIO See Below 264 North
Branch Volga River Randalia
– NV001 Presumptive 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 15330014 6 24 / 3 723 964 345 Yes 21 88% 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 15330014 6 24 / 3 8.9 8.11 8 0 0% No Evaluated Full Class
BWW2 - 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 15330014 6 Ammonia 15 / 2 0.25 0.08 0.06 0 / 0 0% / 0% No Evaluated Full 15330014 6 Chloride 19 / 3 48 32 30 0 / 0 0% / 0% No Evaluated Full 15330014 6 Dissolved Oxygen 24 / 3 12 8 8 0 / 0 0% / 0% No Evaluated Full 15330014 6 pH 24 / 3 8.9 8.11 8 0 / 0 0% / 0% No Evaluated Full 15330014 6 Temperature 23 / 3 24.5 13.8 13.4 NA / 0 NA / 0% Yes Evaluated Full Class
BWW2 - Biological Sampling: Fish: BioNet Site ID Date Drainage Area (mi2) Ecoregion Major Drainage/ Thermal Riffle Site? FIBI score FIBI Class 47c FIBI BIT FIBI Pass/ Fail 264 8/23/18 25 47c MS/WW No 72 Excellent 44 Pass 264 8/25/17 25 47c MS/WW No 64 Good 44 Pass 264 8/26/16 25 47c MS/WW No 60 Good 44 Pass 264 8/12/15 25 47c MS/WW No 64 Good 44 Pass 264 8/14/14 25 47c MS/WW No 76 Excellent 44 Pass Overall
Assessment: Community Assessment
Type Assessment
Result Support
Level Earned
IR Category Actual
IR Category Reason Overall
(Fish only) Monitored Pass (5/5) Full 1 1 Assessment
is monitored because the assessment used two or more samples collected in the
last five years. 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 fish consumption uses
should be assessed as “partially supported.”