to the degree of soil saturation. The water supply is

replenished during the rainy season but gradually depleted

during the long dry season.

 Inputs to the model are the monthly rainfall record

for a 25-yr period, June 1950 through May 1975 at the U. S.

Weather Bureau, Page Field, Ft. Myers, and average long-

term monthly pan evaporation at the Royal Palm Ranger

Station at the Tamiami Trail in the Everglades (U. S.

Department of Commerce. National Oceanic and Atmospheric

Administration, 1950 1974). Pan evaporationn represents

the integrated inputs of the energy sources, solar

radiation and wind.

 Two runs of the model using the same rainfall and pan

evaporation inputs were made. In the first run, natural

conditions as they existed prior to drainage (circa 1900)

were simulated. In the later run, coefficients were

adjusted to create conditions representing the present

(1976) drainage density of the area. Only three

coefficients were changed to represent the difference

between predrained and postdrained conditions.

 Equations for the model, are given in the legend to

Figure 14. The model is quantified and coefficients used

in the model are listed in the-section on quantification

and simulation of the models. Following are brief

explanations of some of the flow equations used in

developing the structure of the water model.