Bathymetric Data for the Florida Keys: Developed in Conjunction with the Florida Keys Benthic Habitat Mapping Project

The bathymetry isobaths thematic layer is derived from digital elevation models using the best available soundings information. These Bathymetric Digital Elevation Models (DEM) were generated from original point soundings collected during hydrographic surveys conducted by the National Ocean Service and its predecessors. Mean High Water shoreline as defined by NOAA nautical charts was used as a constraining boundary and assigned its local elevation relative to the local datum (typically Mean Low Water). DEM grid values outside the shoreline (on land) were assigned null values (-32676). In the event of multiple surveys in a region, the most recent survey soundings were retained. Both 7.5 minute and 1 degree DEMs are available. The 1 degree DEMs were generated from the higher resolution 7.5 minute DEMs which covered the estuary.