Summary

Description

NEW - the following surveys were addedbecause they represent more recentdata than those formerly in the samegeographic location. They are FE0239(1979) and H07841 (1950). Bathymetryfor Raritan Bay was derived from twenty-five surveys containing 230,575soundings. Seventeen overlapping,older, less accurate surveys wereentirely omitted, and the overlap fromone older, less accurate survey wasomitted before tinning the data. Theaverage separation between soundingswas 44 meters. The twenty-five surveysused dated from 1927 to 1988. Thesurvey from 1927 was located in thesoutheast. The eight surveys from 1934to 1936 were located in the extremeeast and west. The remaining surveysdated from 1950 to 1988. The total rangeof sounding data was 1.9 meters to -33.7 meters at mean low water. Meanhigh water values between0.8 and 1.8 meters were assigned to theshoreline. Sixteen points were foundthat were not consistent with thesurrounding data. These were removedprior to tinning. DEM grid values outside the shoreline (on land)were assigned null values (-32676).Raritan Bay has seventeen 7.5 minute DEMs and two one degree DEMs.The 1 degree DEMs were generated from the higher resolution 7.5minute DEMs which covered the estuary. A Digital Elevation Model(DEM) contains a series of elevations ordered from south to northwith the order of the columns from west to east. The DEM isformatted as one ASCII header record (A- record), followed by aseries of profile records (B- records) each of which include a shortB-record header followed by a series of ASCII integer elevations(typically in units of 1 centimeter) per each profile. The lastphysical record of the DEM is an 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.