The National Elevation Dataset is a new elevation product assembled by the U.S. Geological Survey (USGS). It was designed to provide national elevation data in a seamless form with a consistent datum, elevation unit, and projection. Data corrections were made in the assembly process to minimize artifacts, permit edge matching, and fill sliver areas of missing data.  

Specifications

• Coverage: Entire United States
• Source Data:  USGS DEM data (enhanced)
• Projection: Geographic, NAD 83,GRS 80, decimal degrees
• Resolution: one arc-second (approximately 30 meters) for the conterminous United States, Hawaii, and Puerto Rico and a resolution of two arc-seconds for Alaska.
• Each file is delivered in a 1x1 degree block.  DDS can provide each file as individual quads- Call for special requests.
• Media: CD, FTP, Hard-drive

Available Formats

• USGS Standard DEM file format
• ESRI GRID
• .BIL (Intel or Motorola byte order)
• Client specified format (custom pricing).  Call for special requests.

USGS NED Fact Sheet (125 Kb)

DDS, Inc. offers the National Elevation Dataset (Enhanced DEM data) for the entire USA, including Alaska, Hawaii, and Puerto Rico  in 1x1 degree tiles (approx.4,000 files) for only $500!  The data is sampled at 1 arc second/30 meter resolution (60 meter resolution for Alaska).  The following formats are available from DDS:

• ESRI ArcGRID

• .BIL (Motorola and Intel)

• .DEM (additional $500.00)

Order entire USA NED Elevation Dataset at 30 Meters starting at $500

DDS, Inc. offers the National Elevation Dataset (Enhanced DEM data) for the 48 conterminous States in 6x2 degree areas delivered in 1x1 degree tiles (approx. 12 files per area).  The data is sampled at one arc-second/30 meter resolution.   For Alaska, the coverage is 7x6 degree, with a resolution of 60 meters.   The following formats are available from DDS:

• ESRI ArcGRID

• .BIL (Motorola and Intel)

• .DEM

To order 6x2 degree areas for $50, simply locate the area number using either the USA, Alaska, or Hawaii/Puerto Rico Coverage Index and click on    

DDS, Inc. offers the National Elevation Dataset (Enhanced DEM data) for the entire USA, including Alaska, Hawaii, and Puerto Rico  in 1x1 degree tiles (approx.4,000 files) for only $150!  The data is sampled at 3 arc second/90 meter resolution.    This dataset is ideal for compiling large areas (individual States or multiple States) of Digital Elevation Models for base maps or elevation analysis. The following formats are available from DDS:

• ESRI ArcGRID

• .BIL (Motorola and Intel)

• .DEM

DDS, Inc. offers the National Elevation Dataset (Enhanced DEM data) for the entire USA, including Alaska, Hawaii, and Puerto Rico  in 1x1 degree tiles (approx.4,000 files) for only $50!  The data is sampled at 10 arc second/300 meter resolution.    This dataset is ideal for compiling very large areas (multiple States, or the entire USA) of Digital Elevation Models for base maps or elevation analysis. The following formats are available from DDS:

• ESRI ArcGRID

• .BIL (Motorola and Intel)

• .DEM

Digital elevation model (DEM) data are arrays of regularly spaced elevation values referenced horizontally either to a Universal Transverse Mercator (UTM) projection or to a geographic coordinate system. The grid cells are spaced at regular intervals along south to north profiles that are ordered from west to east. The U.S. Geological Survey (USGS) produces five primary types of elevation data: 7.5-minute DEM, 30-minute DEM, 1-degree DEM, 7.5-minute Alaska DEM, and 15-minute Alaska DEM.

Specifications

USGS DEM Fact Sheet (81 Kb)

Available Projections

• UTM - NAD27 / NAD83 / WGS72 / WGS84
• State Plane NAD27 / NAD83
• Latitude / Longitude - NAD27 / NAD83 / WGS72 / WGS84

Available Formats

• USGS Standard DEM file format
• ESRI GRID
• ASCII Text, X,Y,Z format