The U.S. Geological Survey is participating in a joint effort with the University of Maryland Baltimore County and other government agencies to construct a dynamic database of urban development for the Baltimore-Washington region from the late-1700's to the 1990's. The multi-theme temporal database includes a principal transportation data layer that documents the primary roads, railroads, and other transportation features that provided the infrastructure for urban development. A geographic information system was used to collect from various maps at various scales. Compilation criteria, such as connectivity, mobility, lineage, and alignment, were developed to accommodate limitations in the source materials. Visualization techniques such as animation and flight simulation are used to portray the changing transportation infrastructure and its effect on urbanization. The database will be used to study the evolution of the Baltimore-Washington metropolitan area. The principal transportation data layer is essential to illustrate and analyze the regional and temporal aspects of human-induced land transformations. Modeling applications will explore the urban growth process and its correlation to key transportation development.
