Simulation of Steady-State Ground Water and Spring Flow in the Upper Floridan Aquifer of Coastal Citrus and Hernando Counties, Florida

摘要

A digital ground-water flow model was developed to approximate steady-state, predevelopment flow conditions in the Upper Floridan aquifer of coastal west-central Florida. The aquifer is the major source of public water supply and natural spring flow in the area. The aquifer was simulated as a one-layer system with constant vertical recharge and discharge rates. A head-dependent drain function was used to simulate spring flow. Model calibration consisted of adjustments of aquifer transmissivities and recharge-discharge rates until the average absolute error per grid block was less than 3 feet and computed spring discharge was within 10 percent of measured or estimated discharges. The model was used to demonstrate aquifer response to large manmade stresses. Withdrawing 116 cubic feet per second from hypothetical regional well fields resulted in potentiometric-surface drawdowns ranging from 0.1 to 1.7 feet and a drawdown of generally less than 0.2 foot along the coast.