Lake Pepin is a natural lake, but has reservoir-like characteristics and has been deemed impaired for nutrients since placed on the 2002 303(d) list. Therefore, Lake Pepin and the connecting pools require site-specific criteria, as recommended by the Lake Pepin Total Maximum Daily Load Science Advisory Panel (MPCA 2011). In developing the criteria, analysis and modeling were done on data collected between 1985 and 2009 through several different monitoring programs (LimnoTech 2007; MPCA 2012).
A specific model was created using the ECOMSED hydrodynamic model and Row-Column AESOP (RCA) water quality model for Lake Pepin and the connecting pools and channels. The model was created by LimnoTech Inc., and was called the Upper Mississippi River-Lake Pepin Water Quality Model (UMR-LPM) (LimnoTech 2007). The model was used to evaluate potential changes in chlorophyll a, TP, and Secchi transparency over several years. The models predicted water quality changes for various years and presented reduction strategies. Recommendations based on the model results were used to develop site-specific criteria for Lake Pepin and the Upper Mississippi River (MPCA 2011, 2012).
Reference:
LimnoTech. 2007. Upper Mississippi River – Lake Pepin Water Quality Model: Development, Provisional Calibration, and Preliminary Application. Prepared for Minnesota Pollution Control Agency.
MPCA (Minnesota Pollution Control Agency). 2011. Lake Pepin Site Specific Eutrophication Criteria. Minnesota Pollution Control Agency, Environmental Analysis and Outcomes Division. Accessed October 2016. https://www.pca.state.mn.us/sites/default/files/wq-s6-10.pdf Exit .
MPCA (Minnesota Pollution Control Agency). 2012. Mississippi Pools 1 through 8: Developing River, Pool and Lake Pepin Eutrophication Criteria. Document number: wq-s6-09. Accessed October 2016. https://www.pca.state.mn.us/sites/default/files/wq-s6-09.pdf Exit .