Sissabagama Lake 303d Evaluation [NOR_03_11]


Sissabagama Lake (Sawyer Co.) has an average total phosphorus concentration of 25 ug/l which exceeds the WisCALM threshold of 20 ug/l for a seepage lake for 303d listing. It is not known whether there are controllable TP sources in the lake's watershed. Monitoring will be done to determine if there are controllable TP sources and whether the lake should be added to the 303d list. Monitoring and evaluation includes: 1. Analyze existing in-lake and cranberry bog discharge data. Evaluate the significance of internal TP loading. Develop a TP model for the lake. 2. Examine surficial and pre-development sediment samples to compare current and pre-development conditions. Paul Garrison has said he is willing to collect and analyze the samples. 3. Collect TP samples at 1 watershed stream on 5 dates. Flow estimates, and D.O. , temp. and pH measurements will also be made. 4. Collect TP samples from 10 residential wells to evaluate groundwater TP concentrations.


Sissabagama Lake is being evaluated for possible inclusion on the 303d list. The project will determine if inclusion is appropriate.


Performance Measures: These are milestones that will be reported on in the Division Quarterly Report. Please estimate dates in a manner that encourages success. 1) Number of sample sites associated with the project. 11 2) Number of sampling events associated with project. 6 3) Estimated date when sample collection will be complete. October 1, 2010 4) Estimated date when all data will be entered into appropriate database. 12/31/2010 5) Estimated date when final report will be complete. 05/01/2011

QA Measures

Run Project Summary Report

TMDL/303d Projects
Identify Impaired Waters
Reports and Documents
On 5 and 6 October 2010 sediment cores were collected from lakes Sissabagama, Spirit, and North Spirit with a gravity corer. The diatom communities indicate that phosphorus concentrations in all the lakes are higher now than they were historically.
Activities & Recommendations
Monitor or Propose 303(d) Listing
Sissabagama Lake, 2393500 Unnamed stream, 5004138