wells have been constructed in the southern part of Seminole County, but the principal ground-water problem in that county relates to the water available for irrigation and public supplies. /In two irrigation districts, those of Sanford and Oviedo, where large supplies of water for irrigation are obtained from artesian wells, some of the water is highly mineralized. This is significant, because the highly mineralized water is undesirable for irrigation and because with heavy draft the water from many of the wells now yielding water of comparatively low mineral content may become more highly mineralized. Moreover, with increased draft from wells the artesian pressure may be lowered to such an extent that many of the wells will stop flowing.
In May.1933 data relating to wells, -ground water, and the formations penetrated by wells were obtained, and field tests of the chloride content of samples of water from representative wells were made.
The writer is indebted to the well drillers, owners of wells, and other citizens who have contributed information to this investigation. J. Clarence Simpson, of the State Geological Survey, assisted in the field work.
Topography
Relief
Seminole County lies partly in an upland known as the lake region that extends northward and eastward toward the St. Johns River, where it is succeeded by a broad comparatively flat lowland. Surface altitudes
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