A Landmark of Efficiency: Digital Topographic Maps Advance Quickly Across the Nation
Since the first release of the US Topo series of revised digital topographic maps less than 19 months ago, the U.S. Geological Survey (USGS) has published more than 30,800 7.5-minute cells covering more than 50% of the nation’s land area and setting high standards for production efficiency.
“For comparison, the best year the USGS Mapping Program had previously was when we published 2,500 new quadrangle maps in 1972,” said Mark DeMulder, Chief of the USGS National Geospatial Program (NGP). “Now with our digital products, on an annual basis, we’ve exceeded that number by an order of 10.”
For the past 125 years, USGS topographic maps have provided resource managers and the general public with accessible, accurate geographic knowledge for uses that range from recreation to scientific analysis to emergency response.
To meet the need for modern computer-accessible topographic maps that are frequently updated, the USGS established the new US Topo digitally-based national map series. Modeled on the traditional, instantly recognized, paper-based 7.5-minute topographic series, these new maps use the best available government digital data.
A further efficiency gain is that rather than having USGS personnel print, distribute, and store paper copies, the entire US Topo collection is available as digital files and is distributed free of charge, through the Web, via the USGS Store. Digital US Topo map files are designed to be easily printed on demand.
Improved production processes instituted by the USGS National Geospatial Technical Operations Center (NGTOC) will allow the entire contiguous U.S. to be remapped every three years. The USGS is on track to meet this ambitious goal.
In 2009, a developmental product was introduced, a planimetric (no relief) map, called Digital Map – Beta. At the start of 2010, the USGS began adding elevation contours and hydrography (lakes, rivers and streams) and rebranded the map series as US Topo. Currently available US Topo and earlier Digital Map – Beta files are available online.