Lidar point density analysis: implications for identifying water bodies

Scientific Investigations Report 2014-5191
By: , and 



Most airborne topographic light detection and ranging (lidar) systems operate within the near-infrared spectrum. Laser pulses from these systems frequently are absorbed by water and therefore do not generate reflected returns on water bodies in the resulting void regions within the lidar point cloud. Thus, an analysis of lidar voids has implications for identifying water bodies. Data analysis techniques to detect reduced lidar return densities were evaluated for test sites in Blackhawk County, Iowa, and Beltrami County, Minnesota, to delineate contiguous areas that have few or no lidar returns. Results from this study indicated a 5-meter radius moving window with fewer than 23 returns (28 percent of the moving window) was sufficient for delineating void regions. Techniques to provide elevation values for void regions to flatten water features and to force channel flow in the downstream direction also are presented.

Additional publication details

Publication type Report
Publication Subtype USGS Numbered Series
Title Lidar point density analysis: implications for identifying water bodies
Series title Scientific Investigations Report
Series number 2014-5191
DOI 10.3133/sir20145191
Year Published 2014
Language English
Publisher U.S. Geological Survey
Publisher location Reston, VA
Contributing office(s) Earth Resources Observation and Science (EROS) Center
Description iv, 19 p.
Online Only (Y/N) Y
Additional Online Files (Y/N) N