Frog Hollow (aka Volga Lake) IA 01-VOL-292
Fayette County S3T93NR8W 4 mi. NNE of Fayette.
- Assessment Cycle
- 2020
- Release Status
- Final
- Data Collection Period
- Overall IR Category
- 4 - Water is impaired or threatened and a TMDL has been completed or is not needed.
- Trophic
- Eutrophic
- Trend
- Stable
- Created
- 7/15/2020 2:17:48 PM
- Updated
- 10/19/2020 10:14:13 AM
Assessment Summary
The Class A1 uses are assessed (monitored) as “partially supported” (IR 4a) due to algae blooms and high levels of turbidity that violate Iowa’s narrative criteria protecting against aesthetically objectionable conditions. The Class B(LW) (aquatic life) uses are assessed (evaluated) as “partially supported” based on information from the IDNR Fisheries Bureau. Class HH uses are assessed (evaluated) as "fully supported" based on the results of fish tissue monitoring. Note: A TMDL for impairments due to algae and non-algal turbidity at this lake was prepared and approved by EPA in July 2014. The approval of this TMDL moves the impairments due to algae and non-algal turbidity from Iowa's list of Section 303(d) waters (Category 5a of the Integrated Report) to IR Category 4a (impaired; TMDL not required).
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 2014-2018 22330001 Volga Lake (maximum water depth)
Iowa DNR
FT See below 271 Volga Lake
Class A1 -
Indicator Bacteria: No Data Class A1 - pH Site ID Data Source ID # Samples / # Years Maximum Value Mean Value Median Value # Violations % Violations Significantly >10% Violations Assessment Type Support Level 22330001 6 15 / 5 9 8.4 8.5 0 0% NO Monitored Full Class A1 - Lake
TSI's Site ID Data Source ID Parameter Name # Samples / # Years Minimum Value Maximum Value Median Value Median TSI Violation Assessment Type Support Level 22330001 6 Chlorophyll a TSI 15 / 5 46 80 67 YES Monitored Not 22330001 6 Secchi TSI 15 / 5 55 77 70 YES Monitored Not 22330001 6 Total Phosphorus TSI 15 / 5 49 76 68 NA NA NA 22330001 6 Inorganic suspended solids 15 / 5 0.3 31.1 3.8 NA NA NA Class BLW -
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 22330001 6 Ammonia 15 / 5 0.4182 0.11 0.03 0 / 0 0% / 0% NO Monitored Full 22330001 6 Dissolved oxygen 15 / 5 13.9 9.53 9.8 NA / 1 NA / 7% NO Monitored Full 22330001 6 pH 15 / 5 9 8.4 8.5 0 / NA 0% / NA NO Monitored Full 22330001 6 Temperature 15 / 5 26.5 23.2 22.7 0 / 0 0% / 0% NO Monitored Full Class BLW -
Lake Planktonic Cyanobacteria: Site ID Data Source ID # Samples Maximum Cyanobacteria Wet Mass Maximum Cyanobacteria % Composition Median Cyanobacteria Wet Mass Median Cyanobacteria % Composition Median Cyanobacteria Wet Mass = 75th
Percentile Assessment Type Support Level 22330001 6 11 98.484 94.8 % 13.196 72.6 % NO Evaluated NA Class HH – Fish
Tissue Monitoring: Seg ID Site ID Date Species Name Biopart # in sample chlordane result chlordane violation? PCBs result PCBs violation? Hg result Hg violation? Assessment Type Support Level 292 271 7/29/10 largemouth bass fillet 4
0.119 No Evaluated Full 292 271 7/30/10 channel catfish fillet 5 <0.03 No <0.09 No 0.0948 No Evaluated Full
Assessment Key Dates
| 6/5/2012 | TMDL Completed |
| 9/16/2018 | Fixed Monitoring End Date |
| 6/10/2014 | Fixed Monitoring Start Date |
| 7/30/2010 | Fish Tissue Monitoring |
| 7/29/2010 | Fish Tissue Monitoring |
Methods
| 120 | Surveys of fish and game biologists/other professionals |
| 222 | Non-fixed-station monitoring (conventional during key seasons and flows) |
| 260 | Fish tissue analysis |
| 340 | Primary producer surveys (phytoplankton/periphyton/macrophyton) |