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Bathymetry for Pensacola Bay was derived from nine surveys containing63,172 soundings. Six surveys were omitted because they were notconsistent with the other nine surveys and they were not continuous. Theaverage separation between soundings was 77 meters. The surveys dated from1934 to 1991. Approximately 70 percent of the surveys were from 1935. Asurvey from 1982 and a survey from 1991 lie in the southwest section ofthe bay. The range of soundings for the nine surveys was 0.2 to -19.8 metersat mean low water. A mean high water value of 0.4 meters was assigned to theshoreline. Eight points were found that were not consistent with thesurrounding points. These were removed prior to tinning. DEM grid valuesoutside the shoreline (on land) were assigned null values (-32676).Pensacola Bay has nine 7.5 minute DEMs and two one degree DEMs. The 1degree DEMs were generated from the higher resolution 7.5 minute DEMswhich covered the estuary. A Digital Elevation Model (DEM) contains aseries of elevations ordered from south to north with the order ofthe columns from west to east. The DEM is formatted as one ASCIIheader record (A- record), followed by a series of profile records(B- records) each of which include a short B-record header followedby a series of ASCII integer elevations (typically in units of 1centimeter) per each profile. The last physical record of the DEM isan accuracy record (C-record).The 7.5-minute DEM (30- by 30-m data spacing) is cast on theUniversal Transverse Mercator (UTM) projection. It provides coveragein 7.5- by 7.5-minute blocks. Each product provides the samecoverage as a standard USGS 7.5-minute quadrangle but the DEMcontains over edge data. Coverage is available for many estuaries ofthe contiguous United States but is not complete.