Created Highest Quality Scans Ever of near 200,000 Maps
The Organization: U.S. Geological Survey
The USGS started mapping over 130 years ago. These high-cartographic quality paper maps were critical for geologic exploration, population migration, emergency management, urban planning, resource planning, topographic/hypsographic analysis and so much more. These maps were created by thousands of cartographers over a 90 year period across various technical map making procedures. Over the this period, mapping methods changed as the use and technology matured evolving from field sketching and manual cartography to producing paper maps then modernizing to digital data based maps from GIS systems.
The Problem and Solution: Provide map metadata and scanning support services
The previous scanning efforts were performed in the late 1990s when scanning had lossy limitations. Now, with scanning at an accuracy where scratches on paper can be seen, and the storage costs affordable, a scanning project of all available maps kicked off.
The goal of The National Map’s Historical Topographic Map Collection (HTMC) was to scan all the USGS historic topographic maps published by the USGS since the inception of the topographic mapping program in 1884. A Xentity project manager led a group of students to scan and create the metadata for this effort. The effort accurately cataloged and created metadata to accompany high-resolution, geo-referenced digital files representing the legacy lithographic maps. These maps are either no longer available for distribution in print or are being replaced by the new generation of US Topo maps. 75% of the maps were traditional USGS Quads or 1:24,000 scale maps, but there were over 25 various mixes of scale and cell extents covering over 125 years of history. More than a few scanning bulbs were changed out and complicated metadata issues that needed to be addressed to scan these products.
The Outcomes: New data.usgs.gov launched and other parts in work
In 2009, USGS began the release of high-resolution scans of more than 178,000 historical topographic maps of the United States. The topographic map remains an indispensable tool for everyday use in government, science, industry, land management planning, and recreation. The Historical Topographic Map Collection (HTMC) exists online as a digital collection athttp://nationalmap.gov/historical/ and as a physical paper collection of maps in the USGS Clarence King Library in Reston, Virginia.