Elevation | LiDAR
A coordinated effort with the US Geological Survey
LiDAR Coverage and Download Map
The application linked above allows you to easily tell which LiDAR projects cover Tennessee and provides links to data downloads.
In December 2018, The Department of Finance and Administration, STS-GIS Services was awarded $661,000 from the USGS to support another 3DEP project. Plans were to collect lidar for 16 counties in February 2019, but due to flooding issues in West Tennessee, collection is postponed until Nov/Dec. 2019. The West Tennessee project includes two counties (VanBuren, Sequatchie) that were part of a pilot project in 2013. In addition to the USGS funding, other partners for this project include: the Tennessee Department of Transportation, the TennesseeValley Authority, Department of Agriculture, US Army Corps of Engineers and F&A, STS-GIS Services. With this acquisition, the five year plan to acquire lidar for all of Tennessee will be complete.
The following sections provide detailed information about the project's Business Plan/Tech Specs, a LiDAR FAQ sheet, a LiDAR Inventory Map, Business Plan Events and a LiDAR Resources page.
The first step to accomplish our mission on this project is to create a business plan that identifies the business requirements, costs, and benefits of creating a LiDAR derived elevation GIS dataset. In addition, documenting the appropriate technical specifications, and related processes to the LiDAR data, is a foundational element associated with this project.
Using grant funding from FGDC and the NSGIC "50 States Initiative", STS - GIS Services and Applied Geographics conducted regional GIS coordination meetings and stakeholder interviews to gather detailed business requirements that support the argument of why Tennessee should invest in LiDAR/elevation GIS data products.
Here are the results from these coordination/outreach efforts:
1. What is LiDAR?
LiDAR is an optical remote sensing technology that measures properties of scattered light to find range and/or other information of a distant target. This technology is used to measure distance and derive highly accurate elevation data.
2. Does Tennessee have existing elevation data?
Yes. Through the original Tennessee Base Mapping Program (2000-2007), STS - GIS Services developed digital terrain models (DTM) primarily for ortho rectification.
3. Why does Tennessee need LiDAR "enhanced" elevation data?
While very useful, the original DTM data doesn't meet the vertical accuracy requirements for all digital elevation needs in the State.
4. What are the differences between the original DTM data and the LiDAR derived "enhanced" elevation data?
The original photogrammetric derived standard DTM data has a vertical accuracy of +/- seven feet; suitable for a 10 foot contour that meets ASPRS class 2 standards. LiDAR derived "enhanced" elevation data can achieve a vertical accuracy of up to +/- 9cm, suitable for a 1 or 2 foot contour that meets ASPRS class 1 standards.
For more FAQ's regarding LiDAR in general, please see the following document developed by USGS as part of a national assessment for enhanced elevation:
LiDAR, or Light Detection and Ranging, is an evolving technology used to support a wide variety of geospatial business needs at all levels of government and in the private sector.
Instead of defining our own interpretation or understanding of LiDAR, we are providing the following URL's that best describe the technology, resources, associated elevation data products, and how to apply the technology for specific applications.