Data Management Plan

The South New Jersey County Lidar Project is to provide LiDAR data for the New Jersey Department of Environmental Protection (NJ-DEP)

for Cape May, Cumberland, and part of Salem Counties in New Jersey. These datasets will be the initial acquisition to support

the United States Geological Survey (USGS) and the New Jersey Department of Environmental Protection (NJ-DEP). This LiDAR data set was

collected in April 2008 for Cumberland County and covers 502 square miles. The data are classified as follows:

Class 1 - Unclassified/Extracted Features

Class 2 - Bare Earth, Ground

Class 9 - Water

Class 12 - Overlap

Process Steps:

• 2008-07-15 00:00:00 - Leica software was used in the post processing of the airborne GPS and inertial data that is critical to the positioning of the sensor during all flights. This software suite includes Applanix's PosPac and Waypoint's GrafNav solutions. PosPac provides the smoothed best estimate of trajectory (SBET) that is necessary for Leica's post processor to develop the point cloud from the LiDAR missions. The point cloud is the mathematical three dimensional collection of all returns from all laser pulses as determined from the aerial mission. At this point this data is ready for analysis, classification, and filtering to generate a bare earth surface model in which the above ground features are removed from the data set. The point cloud was manipulated within the Leica software; GeoCue, TerraScan, and TerraModeler software was used for the automated data classification, manual cleanup, and bare earth generation from this data. Project specific macros were used to classify the ground and to remove the side overlap between parallel flight lines. All data were manually reviewed and any remaining artifacts removed using functionality provided by TerraScan and TerraModeler. The project was tiled adhering to the State of New Jersey 5000'x5000' tile schema and each tile was saved in LAS format 1.1 including GPS time. Note: The Julian date and year written in the LAS header is actually the file creation date and has no connection to the acquisition date. However the GPS time (second of the week) is registered for each point in the LAS file and the week of acquisition can be deduced from the file name which include the GPS week (1474 = week starting 04/06/2008; 1475 = week starting 04/13/2008). When an area includes data from flightlines acquired over two different GPS weeks, separate files for the data captured in each of the weeks are delivered. For example tile B18D14 has data from both weeks; therefore there are two separate files: B18D14_1474.LAS & B18D14_1475.LAS.
• 2008-07-01 00:00:00 - A Terrascan macro was used to classify the Lidar points inside rivers and lakes from class 2 to class 9. This classification was visually inspected by comparing the bare earth class against the hydro breaklines. Then the elevations were converted from feet to meters to meet the final delivery specifications.
• 2010-07-01 00:00:00 - The NOAA Office for Coastal Management (OCM) received files in LAS format. The files contained LiDAR intensity and elevation measurements. OCM performed the following processing on the data to make it available within Digital Coast: 1. The data were converted from New Jersey State Plane coordinates to geographic coordinates. 2. The data were converted from NAVD88 heights to ellipsoid heights using Geoid03. 3. The LAS header fields were sorted by latitude and updated.

This data can be obtained on-line at the following URL: https://coast.noaa.gov/dataviewer;