Development of an Integrated Surface Water-Groundwater Model for Wetland Restoration and Habitat Evaluation in a Southwest Florida Basin Using MIKE SHE Part II- Development of a Regional Scale Model

The Picayune Strand Restoration Project, a component of the Comprehensive Everglades Restoration Plan (CERP), aims to restore the hydrology of approximately 95 square miles of drained wetland areas in Southwest Florida. The restoration of the Picayune Strand is important because of its location and connectivity to critical preserved areas that serve as wildlife habitat and also the headwaters of the Ten Thousand Islands estuary. The excessive drainage of this area have had several detrimental ecological and hydrologic impacts such as: reduction of groundwater levels, increased freshwater loads to critical estuaries, increase of invasive exotic vegetation and upland species, increased fire frequency, and loss of wildlife habitat connectivity. To evaluate a proposed restoration plan previously developed, two integrated surface water and groundwater models were developed for the area. Two models were developed using MIKE SHE/MIKE 11 in order to simulate different hydrologic aspects of the proposed restoration plan. The previous paper discussed the Phase I HDT model that was developed to simulate the response of the surface water system to short-term high-intensity events. This paper focuses on the Phase II model that was developed to simulate surface water and groundwater responses under a variety of hydrologic conditions. The Phase II model was developed from the Project Implementation Report model (PIR) and was updated to include newly acquired topographic and aquifer data, a more detailed representation of the channel system, and refined structure data. Although the model was based on previous calibrated models the Phase II model calibration process was extensive as a result of significant differences between datasets used in the PIR and Phase II model. The Phase II model was calibrated to dry, wet, and average conditions and does a good job of simulating surface water stage and water table aquifer water levels. Simulated groundwater levels in the lower Tamiami and Sandstone aquifers are adequate but model performance is poorer in these aquifers because of the Limitations of the available groundwater pumpage data. Because the proposed restoration plan will primarily impact the surface water system and the water table aquifer the Phase II model calibration is sufficient to evaluate the long-term benefits of the proposed restoration project.