|Date(s):||Coverage Availability/Geographic Extent:||Footprint:||Source(s):|
|2011||Austin, Waller, Grimes, Walker||1/16 USGS Quadrangle||TNRIS|
|Alternative Data:||1M Hydro-Enforced DEM, 3D Breaklines|
|Derivative Data:||5ft Contours|
|Recommended Uses:||Basemap, Research, Analysis|
The project area is 840 tiles covering approximately 3300 square miles in the Austin / Waller counties of Texas. The project design of the Lidar data acquisition was developed to support a nominal post spacing of 0.5 meter. The AeroMetric, Inc. acquisition covered 440 flights lines in 51 lifts from January 8, 2011 through February 3, 2011. Lidar data collection was performed with a Piper Navajo aircraft, utilizing an Optech Gemini sensor, Serial Number 07SEN201, collecting multiple return x, y, and z data as well as intensity data. Keystone Aerial Surveys was sub-contracted by AeroMetric, Inc. to complete a portion of the acquisition of this area. Keystone completed 26 of the 51 lifts, utilizing an Optech Gemini sensor, Serial Number 05SEN191, in a Cessna 310. the Lidar data was processed to achieve a bare ground surface.
The purpose of this project is to collect and deliver topographic elevation point data derived from multiple return light detection and ranging (Lidar) measurements for north region in Texas. The elevation data will be used as base data for Texas flood plain mapping.
This dataset was acquired through the High Priority Imagery and Data Sets (HPIDS) contract. The contract was created in 2009 to maximize spending power by coordinating geospatial data purchases to share costs and to ensure that acquired data meet high standards of quality. The successor to HPIDS is the StratMap contract, established in 2015.
Lidar data for Texas is made available online through the use of data compression using LASTools. LASTools is an open-source collection of tools for lidar data viewing and manipulation. TNRIS uses the LASzip portion of LASTools for compression\decompression. LASTools provides a lossless compression of the data from las to laz formats.