FLORIDA GEOLOGICAL SURVEY


Figure 12. Approximate average annual runoff, in inches, from areas within Escambia
 and Santa Rosa counties.


 Most of the streams of the two counties originate in the highlands
and flow in sand and gravel-lined streambeds. The low solubility of the
sand and gravel results in water of very low mineral content, generally
less than 30 ppm. The mineral content varies seasonally. During the
rainy season the minerals in the water are diluted, but the color gen-
erally increases because of surface runoff. In the dry season the water
has a slightly higher mineral content, but very little color.
 The quality of available surface water in the area varies from place
to place and from time to time. The seasonal fluctuations follow very
closely the pattern of rainfall. The discussion that follows is concerned
with the availability of surface water with respect to quantity and