This data release contains a digital geospatial dataset generated by the U.S. Geological Survey under a cooperative agreement with the Water Replenishment District of Southern California to characterize the three-dimensional hydrogeology of the Los Angeles Coastal Plain. The geospatial dataset covers about 580 square miles of the largest coastal plain of southern California and contains the unit tops and extents of the three-dimensional chronostratigraphic model (3D CM) and supporting well data. The 3D CM was constructed in EarthVision using methods described in Development of a Groundwater-Simulation Model in the Los Angeles Coastal Plain, Los Angeles County, California; Chapter B (Ponti and Martin, 2021). Specifically, the geospatial database contains (1) a shapefile (point feature class) for the altitude of the top of each chronostratigraphic unit where it exists on a spatial grid in the 3D CM; and (2) a shapefile (point feature class) of wells used to construct the 3D CM including their corresponding name, location, source of well data, and depths of stratigraphic picks.