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OIR GIS Services, with the help of AppGeo/AECOM, TNGIC, and the Tennessee GIS community, has completed its development of a LiDAR/elevation business plan. The eventual goal is to create a very accurate topographic GIS dataset through the use of LiDAR technology (scanning the earth with lasers from an aircraft) to obtain accurate elevations that will support a wide variety of business needs at all levels of government.
The following tabs 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", OIR 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), OIR 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:
Click image to view a larger version.
Project Summary Details:
OIR-GIS Services and Applied Geographics have completed the five regional workshops across the State. We had a good cross section of GIS users from local, State, federal, private, higher ed., utilities, and regional government representatives. All told approximately 160 people shared their experiences and needs for enhanced elevation data.
Click here for a summary report of the regional workshops.
For those of you who were unable to attend, we've included the power point presentations here:
Also, with the help of GeoJobe, we were able to record the Murfreesboro presentation. To view this recording please click on the following link:
In addition to good feedback that will be integrated with the business plan document, another key takeaway from our meetings is to establish some level of "hands-on" workshop geared towards viewing/analyzing/processing LiDAR derived elevation data. OIR-GIS Services and TNGIC will be working together to make this a reality.
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.
USGS Center for LiDAR Information Coordination and Knowledge (CLICK):
National Oceanic and Atmospheric Administration (NOAA):
International LiDAR Mapping Forum:
Web sites and other LiDAR resources:
Iowa Statewide LiDAR Program: