Youthful karst topography and entrenched drainage are two conspicuous geomorphic aids in interpreting the geologic history of the Waco Springs quadrangle. Three high angle, dip slip strike faults of the Balcones system, displaced toward the coast, have off-set all, and exposed most, of the southeastward dipping Comanchean and Gulfian rocks. Broad shallow anticlines are created by a "reversal of dip" on each downthrown fault block. Waco Springs, located in the southwestern part of the map area, has a separate groundwater reservoir from the remainder of the quadrangle, and its discharge is dependent on rainfall concentrated in central Comal County. / text