Simulation of Water Flow and Phosphorus Transport in a Highly Interactive Surface Water/ Groundwater System in the Everglades National Park, Florida


For the Everglades National Park (ENP), HGL developed a MODHMS®-based model of surface and subsurface water interaction to analyze the flow and transport of phosphorous in an area along the southeastern boundary of the ENP. The model was prepared to support the development of the marsh-driven operations plan, which is an aspect of the Comprehensive Everglades Restoration Plan. The fully integrated surface water/groundwater flow and transport model served as an analytical tool to investigate the effects that the construction of levees, canals, pumping stations, and detention basins had on groundwater flow and water quality. The goal of the project was to evaluate how nutrients from agricultural areas outside of the ENP could have affected the park’s ecosystem and to ensure that water levels and flows in basins and drainage canals were maintained to minimize seepage into the ENP. The developed model simulated transient surface water/groundwater flow and transport in double-porosity porous media for the southeastern boundary area of the ENP in response to the operations of the system of canals, levees, and pumping stations, as well as climatic conditions. This model covered an area of more than 400 square kilometers and was calibrated to a set of pre-specified calibration criteria.

Project Highlights
Developed and calibrated an integrated surface water/groundwater flow and transport model for phosphorus in a highly interactive hydrological system.
Used available data for total phosphorus concentrations, potentiometric elevations, canal and detention basin stages, and flow rates through canals between 2000 and 2007 as quantitative calibration targets.
Evaluated marsh-driven operational plan design and effectiveness.
Identified an operational procedure to achieve hydraulic and ecological objectives.