The Bureau of Economic Geology and the Center for Space Research, The University of Texas at Austin (UT), are using airborne lidar to provide elevation data over the Brownsville Resaca Restoration project area. This research results from a collaboration between UT, the City of Brownsville, NASA, and the U.S. Army Corps of Engineers to understand the effects of lidar data resolution and data collection upon the generation of accurate elevation data. The research contributes to technical advice provided by NASA to FEMA in requirements for map modernization in flood-risk assessment. In January 2003 the Bureau will have begun the project with a lidar survey over Brownsville, the Rio Grande, and adjacent portions of Matamoros, Mexico.

Objectives of this project include developing accurate topographic data to assist in the restoration of the Brownsville resaca system and their associated habitats. Another objective is to determine the optimal post spacing of lidar-derived DEM's required for different levels of accuracy in the prediction of flood risk from hydrologic models. A third objective is to investigate the utility of lidar in mapping land cover and assess the effect of varying land-cover resolutions on hydrologic model results and predicted flood risk.