New LiDAR Data Available:
1. 2013 Rutland/Grand Isle data “collection” which includes the Mad River Valley (see map here): 0.7m resolution, Quality Level 2 (QL2). – DEM has been posted, Hillshade and Contours are coming soon.
2. A pre-release portion of the 0.7m Quality Level 2 (QL2) 2014 “Eastern VT” data “collection” which includes a portion of Georgia and stretches south along the lake into Charlotte in Chittenden County (see map here). – DEM and Hillshade have been posted, Contours are coming soon.
Visit VCGI’s Open Data page and search via keyword “lidar” to see the list of new and updated data: http://vcgi.vermont.gov/opendata
Changes to Existing Data:
NOTE: some of the data identified below did NOT make it through the posting process. We are working through some technical issues and hope to resolve them in the next couple of weeks.
1. Updated naming convention to all LiDAR related data. E.g., “Elevation_DEM1m1020_2005.img” is now “Elevation_DEM1M2005_1020.img”.
a. Digital Elevation Model (DEM) data now reflects its “hydro treatment”, e.g., DEM = “pure” DEM; DEMHF = “Hydro-flattened” DEM; DEMHE = “Hydro-enforced” DEM; see USGS’s “Hydro Treatments of LiDAR Derived DEMs” powerpoint for details.
2. All downloadable data layers are in their original, vendor-delivered tiling structure, re-projected to VT State Plane Coordinate System NAD83 meters, Zunits meters and the Erdas Imagine format. This primarily affected the following collections:
a. 2008 “Lower” Missisquoi – Reimported to original 1.6m, “hydro-flattened” DEM format;
b. 2010 “Upper” Missisquoi (a.k.a. “Rock River”) – Reimported to original 1.6m, “hydro-flattened” DEM format;
c. 2012 Bennington County – Reimported to original 2m, “pure” DEM format;
3. Only DEMs and contours (DEM/DEMHE/DEMHF) are provided in tiled format. Other derivatives are in single mosaic file format only.
a. When contour data was part of the original vendor delivery they are in the same tile index structure as the DEMs.
b. When contour data was not part of the original vendor delivery and created by VCGI in 2013/2014 they are in the “Ortho9” tile index.
4. All primary (DEMs) and secondary derivatives (ASPECT, DSM, HILSHD, nDSM & SLOPE) are available in a single, mosaic file format covering the full “collection” extent.
Changes to Metadata:
- All LiDAR metadata files have been updated to latest EGC format (May 2016).
- For original vendor metadata see “All VT LiDAR on an External drive” main page for all project level metadata in a central location (these are original vendor metadata for LAS data).