PAMAP Elevation Data
The Program is completing an unprecedented project to collect and process high-resolution LiDAR elevation data for the entire state. Pennsylvania is one of the first states in the nation to complete collection of this level of elevation data for the entire state. LiDAR, an acronym for light detection and ranging, is used to produce various elevation data products including point based digital terrain models (DTM), grid-based digital elevation models (DEM), and contours. In addition to these “end user” products, LiDAR processing generates other data resources, including the raw point cloud, processed points, and breaklines.
The LiDAR data is primarily acquired to produce an accurate and high-resolution bare earth model of Pennsylvania. The PAMAP Program has processed the LiDAR data to derive bare earth data products. The data products include:
- Digital Elevation Model – a 3.2-foot pixel (1-meter equivalent) raster GeoTIFF Digital Elevation Model (DEM). Each pixel in the DEM has an interpolated elevation value. Each DEM is approximately 37.5 MB in size.
- Contours – a 3D shapefile of 2-foot contours is provided for each tile. Each contour is attributed with its elevation value and whether it is an intermediate (2-foot interval) or index (10-foot interval) contour. The size of each shapefile varies.
- Breaklines – a 3D shapefile of breaklines is provided for each tile. The breaklines are interpreted from the PAMAP orthophotos and the LiDAR data is used to provide elevation (z-values) to each line. The breaklines are used in the creation of the DEM and contours. Each breakline is attributed for feature type (e.g. edge of road); the feature types are documented in metadata. The size of each shapefile varies.
The status of the LiDAR project (December 2010) is shown below.
Where to get Data
PAMAP LiDAR and derived products can be acquired from the following organizations. Data may be available from other sources as well.
DEMs, contours and breaklines are provided through FTP and map services at the Pennsylvania Spatial Data Access Clearinghouse (PASDA).
All data products are available for bulk and/or offline acquisition from the Pennsylvania State Data Center here.
Information on data issues for PAMAP LiDAR and elevation products can be found here.
Frequently Asked Questions
The Program’s LiDAR Frequently Asked Questions (FAQ) can be found here.
PAMAP DEM Hillshade Service published by the Pennsylvania Spatial Data Access Clearinghouse.
Sample image of Hillshade generated from preliminary LiDAR data - site in Pittsburgh, Allegheny County. 10,000 feet square tile.
Contours from LiDAR data superimposed on 2005 orthoimagery. Luzerne County Courthouse.
Breaklines superimposed on 2007 orthoimagery. Camp Hill area.