Diamond Lake IA 03-NSK-861
Poweshiek County S2T78NR15W approx 2.5 mi SW of Montezuma.
- Cycle
- 2024
- Release Status
- Final
- Overall IR
- 5 - Water is impaired or threatened and a TMDL is needed.
- Trophic
- Eutrophic
- Trend
- Stable
- Created
- 11/1/2023 8:12:54 AM
- Updated
- 2/2/2024 2:18:02 PM
The Class BLW use was assessed (monitored) as “not supported” due to high levels of algae at this lake suggested impairment due to adverse impacts on plant/animal communities. Additionally, the Class BLW use was assessed as “WINOFI” due to poor water quality caused by an exotic fish population (common carp). The Class C use was assessed (monitored) as “fully supported” based on water quality monitoring data and drinking water compliance monitoring required by the DNR. The Class HH (fish consumption) use was assessed as "fully supported" based on fish tissue sampling data.
Data Sources: Data Source Data Source ID Data Type Data Age Site ID Site
Name Site
Description Iowa DNR 6 WQ CY 2018-2022 22790005 Diamond
Lake
Iowa DNR 6 FT See Below 1292 Diamond Lake
Class BLW - 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 22790005 6 Chlorophyll a TSI 15 / 5 35 80 66 YES Mon Not 22790005 6 Inorganic suspended solids 15 / 5 1.7 21 7 NA NA NA Class BLW - Binomial Parameters: Site ID Data Source ID Parameter Name # Samples / # Years Minimum Value Maximum Value Mean Value # Violations # Acute / Chronic Violations Violations needed for impairment Violates Significantly >10% Rule? Assessment Type Support Level 22790005 6 Dissolved Oxygen 15 / 5 3.5 13.4 8.4 1 NA / NA 4 NO Mon Full 22790005 6 pH 15 / 5 7.3 8.8 8.2 0 NA / NA 4 NO Mon Full 22790005 6 Temperature 15 / 5 18.8 28.9 24.1 0 NA / NA 4 NO Mon 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 Concentration = 75th Percentile Assessment Type Support Level 22790005 6 8 26.00202992 91% 5.712414695 27% NO Evaluated NA Class BLW - Toxic Parameters: Site ID Data Source ID Parameter Name # Samples / # Years Maximum Value Mean Value Median Value # Acute / Chronic Violations >1 Acute / Chronic Violation Assessment Type Support Level 22790005 6 Ammonia 15 / 5 0.657 0.16 0.03 0 / 0 NO Mon Full Class C - Binomial Parameters: Site ID Data Source ID Parameter Name # Samples / # Years Minimum Value Maximum Value Mean Value Median Value # Violations Violates Significantly >10% Rule? Assessment Type Support Level 22790005 6 Inorganic nitrogen (nitrate and nitrite) 14 / 5 0.02 1.36 0.34 0.11 0 NO Mon Full 22790005 6 pH 15 / 5 7.3 8.8 8.2 8.2 0 NO Mon Full Class C - Iowa Drinking Water Compliance Report: Compliance monitoring required by the Iowa DNR Water Supply Operations and Engineering Sections did not show violations of finished water caused by source water at the Montezuma Muni Water Supply facility during the 2020-22 monitoring period. The results of compliance monitoring as reported in annual compliance reports are available at the following location at the Iowa DNR’s home page: https://www.iowadnr.gov/Environmental-Protection/Water-Quality/Water-Supply-Engineering/Annual-Compliance-Report. Class HH - Fish
Tissue Sampling: Site ID Biopart Year Species # in sample / # of samples Avg Length (cm) (Avg) Hg (ppm) Chlordane (ppm) Sum PCBs (ppm) 1292 fillet 2013 channel catfish 5 43 0.05 <0.2 <0.6 1292 tissue plug 2013 largemouth bass 5 35.6 0.124
Support Level Full