The bathymetry data were created by NOAA Coastal Services Center from depth soundings distributed through the NOAA Geophysical Data System (GEODAS). Values were extracted from the GEODAS database using the default HYD93 download and tabulated with header information. These data are believed to be complete within the area of interest.
In cases where multiple soundings occurred within 50 meters, older soundings were discarded. The remaining data available from 1934 through 1996 surveys were included in layer creation. Depth values were created by building a Triangulated Irregular Network (TIN) and converted to a grid using the methods described in the metadata provided with the ArcView extension.