Spatially distributed modeling of surface water flow dynamics in the Everglades ridge and slough landscape

Abstract

Summary A two-dimensional, spatially distributed flow dynamics model was developed and tested for a 1.5 by 4 km area of the patterned ridge and slough landscape of the Florida Everglades. This model is intended to support a deepened understanding of the system ecohydrological dynamics, and provide a useful tool for management decision support. The model was constructed with a fine enough mesh structure to ensure proper representation of ridge and slough topographic detail as well as capture local hydrologic influences. Upstream and downstream stage data collected near the study area in central Water Conservation Area 3A were used to establish the initial and boundary conditions. Water velocities measured in the ridges and sloughs over a 3-year period were used to calibrate and verify the model. Hydraulic resistance was computed using a power-law relationship with water depth. The simulated water levels, water depths, and flow velocities showed good agreement with the 3-year field-monitored data with percent model errors of approximately 4%, 12%, and 10%, respectively. Computed differences in hydraulic resistance between ridge and slough were reduced significantly during the storm season compared to the dry season. This suggests that more solute and suspended solid mass can be redistributed from the sloughs to the ridges in particular during wet seasons, due to the weakened heterogeneity of hydraulic resistance during high flows.