Simulated effects of ASR injection and withdrawals in the Floridian aquifer system near Lake Okeechobee Florida - a first approximation

The primary objective of this study is to assess the potential effects of injecting and then withdrawing 1.0 bgd of water into the Upper Floridan aquifer near Lake Okeechobee on changes in Floridan aquifer system heads near the well sites and north of the lake.

The project objectives will be met by simulating the effects of injecting, and then withdrawing, water near Lake Okeechobee on the Floridan aquifer flow system using the USGS ‘Mega’ model (Sepulveda, 2002). The Mega model extends from the Suwannee River south to the middle of Lake Okeechobee, and from coast to coast. The model has a constant surficial aquifer fixed head array and is vertically discretized to simulate ground-water flow in both the Upper and Lower Floridan aquifers. The model input files, which are presently formatted for inclusion in the original version of the MODFLOW model, will need to be converted to the newer USGS MODFLOW-2000 format (Harbaugh and others, 2000). The locations of injection/withdrawal sites and accompanying rates will be provided by project development team members. Because of the close proximity of the model’s southern boundary to the proposed injection sites, the model cannot be used to evaluate the possible effects of injections and withdrawals to areas south of the lake.