Badger Lake IA 04-UDM-1291
Webster County S19T90NR28W 4.5 mi N of Fort Dodge.
- Cycle
- 2018
- Release Status
- Final
- Overall IR
- 5 - Water is impaired or threatened and a TMDL is needed.
- Trophic
- Eutrophic
- Trend
- Declining
- Created
- 1/30/2019 2:28:35 PM
- Updated
- 1/30/2019 2:41:41 PM
The Class A1 (primary contact recreation) uses are assessed (monitored) as "partially supported" due to aesthetically objectionable conditions caused by algae blooms. The Class B(LW) (aquatic life) uses are assessed (evaluated) as “partially supported” (IR 3b) due to siltation and water quality impacts of common carp. Fish consumption uses remain “not assessed.” Sources of data for this assessment include (1) results of the statewide survey of Iowa lakes conducted from 2012 through 2016 by Iowa State University (ISU), and (2) information from the IDNR Fisheries Bureau.
For the 2018 assessment/listing cycle, the Class A1 (primary contact recreation) uses of Badger Lake are assessed (monitored) as "partially supported" due to aesthetically objectionable conditions caused by algae blooms based on information from the ISU lake survey. Using the median values from these surveys from 2012-2016 (approximately 15 samples), Carlson 's (1977) trophic state indices for Secchi depth, chlorophyll a, and total phosphorus were 64, 65, and 68 respectively for Badger Lake. According to Carlson (1977) the Secchi depth, chlorophyll a, and total phosphorus values all place Badger Lake in the Eutrophic category. These values suggest high levels of chlorophyll a and suspended algae in the water, moderately poor water transparency, and high levels of phosphorus in the water column. The data show no violations of the Class A1 criterion for pH in 15 samples. The level of inorganic suspended solids was moderately high at Badger Lake, and does suggest that non-algal turbidity may contribute to the impairment at this lake. The median level of inorganic suspended solids in Badger Lake (4.3 mg/L) was ranked 87th among the 138 lakes by the ISU lake survey. Data from the 2012-2016 ISU lake survey suggest a small population of cyanobacteria exists at Badger Lake. These data show that cyanobacteria comprised 5% of the phytoplankton wet mass at this lake. The median cyanobacteria wet mass (1.2 mg/L) was ranked 7th of the 138 lakes sampled. The Class B(LW) (aquatic life) uses are assessed (evaluated) as “partially supported” based on information from the DNR Fisheries Bureau. Information from the DNR Fisheries Bureau suggests that siltation and the impacts of common carp on turbidity at this lake impair the aquatic life uses (partial support/evaluated). Results of the ISU lake survey from 2012-2016 show there were no violations of the criterion for ammonia in 15 samples(0%), one violation of the criterion for dissolved oxygen in 15 samples(7%), and no violations of the criterion for pH in 15 samples(0%). Based on DNR's assessment methodology these violations are not significantly greater than 10% of the samples. Fish consumption uses remain "not assessed" due to the lack of fish contaminant monitoring in this lake.