Modeling Surface and Subsurface Hydrologic Interactions in the Biscayne Bay Coastal Wetlands

Restoration of the South Florida ecosystem is a major undertaking for the U.S. Army Corps of Engineers and the South Florida Water Management District in the federally approved Comprehensive Environmental Restoration Plan (CERP). Many competing entities have an interest in the restoration process which will probably include physical changes to the land surface and adjustments to water deliveries. Restoration plans will be developed using numerical hydrologic models that optimize the benefits among the various stakeholders. Since the health of the South Florida ecosystem is impacted by subtle exchanges of surface and subsurface water, there is a need for great accuracy in the models that will identify the best restoration plans. The accuracy needed for design level simulations of the various projects approaches +/- 0.1 ft in the water elevations. Models with insufficient physical processes and/or highly schematized models with large grid or mesh induced error will not be sufficient to make design level simulation of South Florida hydrologic processes. Additionally, since a large number of models will be set up and analyzed, effective and efficient graphical user interfaces are needed for the models. This paper presents the results of testing WASH123D code to simulate surface water and subsurface interactions in the groundwater system.