Summary

Description

EarthData International collected ADS-50 derived LiDAR over a portion of Hillsborough and Manatee Counties with a one meter post spacing. The period of collection was between 12 January and 20 January 2007. The collection was performed by EarthData Aviation, using a Leica ALS-50 LiDAR system, including an inertial measuring unit (IMU) and a dual frequency GPS receiver. This project required eleven lifts of flight lines be collected. The product generated consisted of LiDAR bare earth elevation models in LAS format. This data set is one component of a digital terrain model (DTM) for the Southwest Florida Water Management District's FY 2007 Hillsborough County - Watershed Management Plan Topographic Information Mapping (L762) and FY 2007 Little Manatee River Watershed Management Plan (L604), encompassing approximately 453 square miles in Hillsborough County and 82 square miles in Manatee County. The 2007 LiDAR data set is comprised of 3-D mass points delivered in the LAS file format based upon the District's 5,000' x 5,000' grid with 505 cells in the Hillsborough area with an additional 91 cells in the Little Manatee area. An additional 12 cells were added to the Hillsborough area. The other DTM component is 2-D and 3-D breakline features in the ESRI ArcGIS Personal Geodatabase format. The breaklines were collected using Aerial photography captured for the Southwest Florida Water Management District FY 2007 Digital Orthophoto (B089) Central District One-foot Orthophoto project. The stream breaklines were the corrected to the hillshade LiDAR data. Contours (2-foot) were generated from the DTM that meet the National Standard for Spatial Data Accuracy (NSSDA) for 2-foot contours (FEMA specifications). Bare earth LiDAR mass point data display a vertical accuracy of at least 0.3-feet root mean square (RMSE) in open and unobscured areas with standard reflective quality.