Merrick-Surdex Joint Venture, LLP
20180730
DEM .img
raster digital data
A one-meter (1m) cell size Digital Elevation Model (DEM) raster was created from the ground classified lidar points plus the breaklines. The files are delivered in tile format (1000m by 1000m), The rasters are delivered in Erdas Imagine format (.img).
This project will support the 3DEP mission, the Federal Emergency Management Agency (FEMA) Risk Mapping,
Assessment and Planning (MAP) program and the Natural Resources Conservation Service (NRCS) high resolution elevation enterprise program. The entire AOI covers approximately 11,100 square miles in total in Southeastern Nebraska. This project is broken into four delivery blocks. The following block square miles are approximations: Block1 = 2304, Block2 = 3412, Block3 = 2995, Block4 = 2399.
Raster File Type = IMG
Bit Depth/Pixel Type = 32-bit float
Raster Cell Size = 1 meter
Interpolation or Resampling Technique = Triangulated Irregular Network (TIN)
Required Vertical Accuracy = 19.6cm NVA
20180327
20180419
ground condition
Unknown
-100.962912
-99.626211
41.010345
39.986531
334899.999995186
446547.406381801
4540099.99999695
4428052.99953537
None
Breaklines
Elevation Data
Lidar
DSM
Intensity
None
Southeast Nebraska
No restrictions apply to these data.
None. However, users should be aware that temporal changes may have occurred since this dataset was collected and that some parts of these data may no longer represent actual surface conditions. Users should not use these data for critical applications without a full awareness of its limitations. Acknowledgement of the U.S. Geological Survey would be appreciated for products derived from these data.
Data covers the entire area specified for this project.
The dataset was reviewed to ensure completeness and accuracy.
This data set was tested to meet ASPRS Positional Accuracy Standard for Digital Geospatial Data (2014) for a 10-cm RMSEz Vertical Accuracy Class. Actual NVA accuracy was found to be RMSEz = 2.904cm, equating to +/- 5.692cm at the 95% confidence level. Actual VVA accuracy was found to be +/-11.197cm at the 95th percentile.
0.063
Bare-Earth Non-Vegetated Vertical Accuracy (NVA) tested 0.063 meters vertical accuracy at the 95 percent confidence level. Sixty-six (66) NVA points were used and validated against the DEM.
0.112
Vegetated Vertical Accuracy (VVA) tested 0.112 meters vertical accuracy at the 95th percentile. Forty-seven (47) VVA points were used and validated against the DEM.
Using MARS software a one-meter (1m) 32-bit floating point DEM raster in Erdas Imagine format (.img) were created using the ground classified lidar points along with the breaklines. The files are delivered in 1000m by 1000m tiles.
20180730
Raster
Pixel
1000
1000
Universal Transverse Mercator
14
0.9996
-99.000000
0.000000
500000
0
row and column
1.0
1.0
meters
D_NAD_1983_2011
Geodetic Reference System 80
6378137.000000
298.257222
North American Vertical Datum of 1988 Geoid12B
.001
meters
Explicit elevation coordinate included with horizontal coordinates
20180730
Merrick-Surdex Joint Venture, LLP
mailing and physical address
520 Spirit of St. Louis Blvd
Chesterfield
MO
63005
USA
636-368-4436
FGDC Content Standards for Digital Geospatial Metadata
FGDC-STD-001-1998