Development of a Seamless Topographic / Bathymetric Digital Terrain Model for Tampa Bay, Florida

This applications paper presents the methods used to create a seamless topobathy digital terrain model (DTM) at 50-foot resolution intended to support hurricane storm surge modeling in Tampa Bay, Florida. Lidar, bathymetry, and various breakline data were integrated using the Terrain Data Set structure in ArcGIS®. The use of the Terrain Data Set structure allowed for embedding large data sets (such as lidar points) and archiving them after DTM creation while maintaining topographic analysis capabilities. The bathymetric data, natively referenced to Mean Sea Level (MSL), were converted to North American Vertical Datum of 1988 (NAVD88) using an inverse distance weighted average offset from the three nearest NOAA tidal benchmark stations; results of this conversion were within 6.1 centimeters of those produced by NOAA VDatum software in a quality control test area. This methodology can therefore be used in coastal regions of other countries.