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Spring 2011 Rhode Island Statewide LiDAR Data - Provisional Release

Detailed elevation data were collected with airborne LiDAR technology for the entire area of Rhode Island between April 22 and May 6, 2011.

This data collection was a component of the larger Northeast LiDAR Project. This multi-state regional initiative was primarily funded by the American Recovery and Reinvestment Act and is lead by the Maine Office of GIS, facilitated by the USGS Geospatial Liaison Network, and managed by the USGS National Geospatial Technical Operations Center. Locally, this project is coordinated by RIGIS and the URI Environmental Data Center.

Basic specifications for the data acquisition:
1) 1 meter nominal pulse spacing
2) National Spatial Standard for Spatial Data Accuracy (NSSDA) Fundamental Vertical Accuracy (FVA) 29.4cm @ 95% confidence, based on 15cm RMSEz in open terrain land cover.
3) Horizontal coordinate system: NAD83 UTM Zone 19 North, meters
4) Vertical reference: NAVD88 (GEOID99), meters
5) No tidal coordination
6) Meet or exceed standards defined in version 12 of the USGS National Geospatial Program Base Lidar Specification (PDF).

The expanded LiDAR collection coverage for this project (entire state vs just coastal communities) and higher sampling density (1m nominal point spacing vs 2m) are both upgrades over what was specified for the standard regional product project deliverables. These upgrades were made possible by the coordination of contributing funds from the Rhode Island Statewide Planning Program (Federal Highway Administration), Rhode Island Chapter of The Nature Conservancy, and USDA Natural Resource Conservation Service Rhode Island State Office. Credit is also due to all the agencies and organizations that contributed their time to help build support for the Rhode Island component of the Northeast LiDAR Project.

Contracted deliverables for Rhode Island:
1) Raw point cloud data, delivered as flight swaths (LAS 1.2 file format)
2) Partially classified point cloud data, delivered as 1500x1500 meter tiles (LAS 1.2 file format; includes intensity data and the following classes: 1 (unclassified); 2 (ground); 7 (noise); 9 (inland water hydro-flattened with the assistance of breaklines); 10 (ignored ground - 1m buffer around hydro-flattened and bare water features); 14 (bare water - estuarine and marine water, not hydro-flattened)).
3) Total file size for all partially classified LAS files for Rhode Island is 258 GB, representing a total of 1553 tiles.
4) 1-meter resolution bare earth digital elevation model, delivered as 1500x1500 meter tiles (ERDAS IMG format, total file size for all DEM files for Rhode Island is 13 GB)
5) Supporting documentation, including QA/QC results and metadata

These data may also be distributed at some point in the future via USGS CLICK and the NOAA Coastal Services Center Digital Coast, but the timing for when this may happen is unknown.