Could LiDAR be the Answer?
Flooding is a leading cause of natural disaster in the United States. High-quality, digital mapping is essential to communicating flood hazard areas to those at risk. Urban expansion and land development have significantly altered the earth surface. New roads and flood drainage structures have an effect on projected floodwater depths, and land subsidence can be significant in coastal areas. As a result, flood disasters over the past years have created an increasing demand for precise, accurate and tangible data of the earth’s surface
The key to anticipating, preparing for, and insuring against flooding can be summed up in one word – maps. Flood maps require precise elevation data – topography, and hydrology data – information about the behavior and properties of water, in order to predict where floodwaters are likely to flow and cause flood damage.
Currently there is a serious deficiency in the acquirement of accurate elevation data to accurately measure the shape of the land surface that is critical in determining the direction, velocity, and depth of floodwaters
LiDAR, light detection and ranging, is an incredible technology that captures our world in 3D: earth surface terrain, cities, building interiors, and much more. It works by scanning the environment with pulses of laser light, many times per second, and measuring reflections. The result is an enormous number of tightly spaced points in 3D, revealing both surfaces (water surface, ground, building surfaces) and less regular objects (height of vegetation, or power lines).
LiDAR digital elevation data has been used for a number of different applications, including flood insurance rate maps, generating contours, creating three-dimensional terrain views, modeling land use slopes, streams, wetlands, drainage basins, property valuation, utility surveys, forestry, and agriculture research.
LiDAR technology is becoming the ideal cost saving application for many counties and municipalities across Georgia. Airborne lidar elevation data is the methodology to produce accurate, reliable, and detailed maps of the ground more speedily and, in many cases, more economically than almost any other elevation data collection method. LIDAR data has also been instrumental in the interpretation of drainage patterns, producing detailed drainage network maps capturing even small drainage features, such as narrow ditches, and water-ducts.
The goal of this article is to tweak your curiosity and ask; “What can the technology of LiDAR digital elevation data do for my community”? In what ways can LiDAR help manage expenditures in these tough economic times? What actions are necessary to collect LiDAR elevation data for the State of Georgia?