U.S. Geological Survey: The National Map Railroad GIS Dataset Development
The National Map is a collaborative digital mapping initiative coordinated by the United States Geological Survey (USGS). Its aim is to deliver and improve topographic information for the nation. It has many uses ranging from recreation to scientific analysis and emergency management planning and response. Executive Order 12906, issued in 1994 and amended in 2003, called for the establishment of a National Spatial Data Infrastructure (NSDI), whose goal is to reduce duplication of effort among governmental agencies at all levels. As part of the NSDI, The National Map serves as a warehouse of collected geospatial data, available for public access via the Internet.
The acquisition of geospatial datasets for The National Map began with the incorporation of USGSDigital Line Graph (DLG) data prepared from photogrammetric mapping at scales from 1:1,000,000 to 1:100,000. While nationwide in extent, these datasets have limited utility due to the small-scale preparation.
USGS is developing programs to capture United States infrastructure data at map accuracy standards of up to 1:24,000. It was uncertain how costly it would be to acquire nationwide data suitable for use at medium-scales. To investigate the scope of the problem, USGS contracted with AeroMetric to conduct a pilot project to assess the costs and necessary methodologies to capture valid, high quality digital map data for The National Map. The map feature class selected was railroads, and the Project Area selected was in Oregon.
AeroMetric prepared a two-phase approach to identifying, then quantifying the cost of data acquisition on a statewide scale. In Phase 1, sources of high-quality digital map data for railroads were identified. Phase 2 consisted of the acquisition and processing of data for incorporation into The National Map.
Illinois State Tollway: Geospatial Project Catalog 
