This study supported the Southwest Florida Water Management District’s (SWFWMD) re-evaluation of minimum lake levels for seven lakes in the Highlands Ridge in Central Florida, including Lakes Letta and Lotela. These lakes are currently not meeting the established minimum levels. Since levels were first established for many of the Southern Water Use Caution Area (SWUCA) lakes, improvements to the methods used to establish minimum levels have been made. The SWFWMD undertook an effort to re-evaluate the levels and, if necessary, adopt updated levels. The study report described the development of an alternative hydrologic modeling tool to provide a hydrologic foundation for establishment of minimum lake levels. Under two task orders associated with this project, Taylor Engineering (as Interflow Engineering) gathered relevant data, developed an analytical water budget, and then created an integrated groundwater and surface water model using MIKE SHE/MIKE-11. Taylor Engineering calibrated the water budget model using multiple years of rainfall, groundwater levels, and lake levels, and then extended the model output to create a 60-year dataset using statistical correlations with rainfall. Taylor Engineering used the calibrated model to evaluate the long-term water budgets and lake levels. Changes to the lake levels and water budget terms were evaluated in response to potential management actions, including reductions in pumpage and lake augmentation.