TxDOT Maps Texas History Continued from page 21 For more than two years, the THO team solicited information from libraries, museums, and repositories and obtained maps. Maps were supplied in a variety of formats including scanned hard copies, photographic reprints, microfilm, digital photography, and tracings of hard-copy maps on vellum. feature classes to serve as an index joined to the source map information in SQL Server. The team also created the Metadata Miner, another ArcObjects-based application, to automate the generation of historic map-imagespecific metadata in Federal Geographic Data Committee (FGDC) format using information mined from a SQL Server database. The resource information developed from the THO project is available to TxDOT and approved consultants to develop historic trends in land use, development, and vegetation and manage the state's cultural resources while planning state road and highway projects. "Just about every project we do for TxDOT 22 ArcUser Summer 2009 includes use of the Texas Historic Overlay in the early stages to identify likely locations for resources that once existed in the landscape," said Eugene Foster, senior scientist at PBS&J and project manager for the THO project. "We typically use that information early on to compare and refine project alternatives." The data is used to develop scopes and budgets for field surveys. It also guides historians and archeologists in field surveys and right-of-way acquisitions. For instance, PBS&J was contracted by TxDOT to evaluate the possibility of unmarked graves in the area surrounding a proposed bridge on State Highway 130 over State Highway 71 near Austin. PBS&J planners needed to survey about 15.7 acres of land located adjacent to the proposed bridge site. The team pulled area maps from THO to locate cemeteries. Then they overlaid remotely sensed data to find unmarked graves at the site. While no unmarked graves were located, the team was able to help TxDOT see the old State Highway 71 alignment as well as some potential historic sites. The entire site analysis took three days. Jim Abbott, project manager for the TxDOT Environmental Division, said, "The ability to access and compare historic maps at the desktop provides us with a powerful www.esri.com