Location: Southeast Watershed Research
Title: Comparison of NOAA lidar data at 1.5 and 3 meter resolutions, for adequate watershed delineation in Tift County, Georgia, USAAuthor
ELLZEY, DYLAN - Valdosta State University | |
Coffin, Alisa | |
Bosch, David |
Submitted to: Meeting Abstract
Publication Type: Abstract Only Publication Acceptance Date: 4/7/2017 Publication Date: 4/13/2017 Citation: Ellzey, D., Coffin, A.W., Bosch, D.D. 2017. Comparison of NOAA lidar data at 1.5 and 3 meter resolutions, for adequate watershed delineation in Tift County, Georgia, USA. Meeting. [abstract] Presented at 23rd Annual Undergarduate Research Symposium, Valdosta State University, Valdosta, Georgia, April 11-13, 2017. Interpretive Summary: The USDA Southeast Watershed Research Laboratory is located in Tifton, Ga, and performs ongoing watershed research for the Tift County area, as well as surrounding counties. Current watershed delineations are based on hand drawn analyses of USGS topographic sheets, and require updating. Light Detection and Ranging (LiDAR) elevation data are frequently used to delineate watersheds, as precision and accuracy of LiDAR data are very high. This study compares the current hand drawn watershed delineations with boundaries derived from LiDAR elevation data using a geographic information system (GIS). Watershed boundaries were created for three small watersheds, based on LiDAR data, sampled at different distances to create raster surfaces of differing pixel sizes. The boundaries were also created with and without water control structures such as under-road culverts and drainage ways to compare the effects of adding in these control structures. Results showed that, for small watershed areas, the inclusion of water control structures, and the pixel size of the raster surface, make a substantial difference in the boundary area, perimeter and shape. Technical Abstract: The USDA Southeast Watershed Research Laboratory is located in Tifton, Ga, and performs ongoing watershed research for the Tift County area, as well as surrounding counties. Current watershed delineations are based on 1972-1977, 7.5-minute USGS Quadrangle sheets, and require updating. Light Detection and Ranging (LiDAR) elevation data are frequently used to update watershed delineations, as precision and accuracy of LiDAR surface models are very high. This study compares the current hand drawn watershed delineations with boundaries derived from LiDAR elevation data using a geographic information system (GIS). Watershed boundaries were created for three small watersheds, based on LiDAR data surface models resampled at multiple resolutions, both with and without water control structures such as under-road culverts and drainage ways. Results showed that, for small watershed areas, the inclusion of water control structures, and the resolution of surface models, make a substantial difference in the boundary area, perimeter and shape. |