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Why are there no trails, Public Land Survey System (PLSS), powerlines, etc. on US Topos?

The original USGS 7.5-minute topographic map series (1945-1992) included feature classes that are not yet shown on US Topos. Examples include recreational trails, pipelines, power lines, survey markers, many types of boundaries, and many types of buildings. The USGS no longer does field verification or other primary data collection for these feature classes, and there are no national data sources suitable for general-purpose, 1:24,000-scale maps. For many of these feature classes, USGS is working with other agencies to develop data. Over time, as these data become available and are included in The National Map, that content will be added to the US Topos. Published articles providing an overview of US Topo content and general project philosophy.
 
Because US Topo maps are mass produced from GIS databases, some features shown on traditional maps may never be included on US Topo. For example, it is doubtful a national database of isolated windmills and water tanks will ever be built, nor is it likely that the owners of cross-country pipelines or power lines will consent to showing these features.
 
The two most requested additional feature classes are Public Land Survey System (PLSS) and recreational trails. For these two feature classes we are optimistic about eventually achieving the content of traditional maps, or perhaps even better.
 
  • During the second 3-year US Topo production cycle (2013-15) progress has been made on adding PLSS. As of August 2014, PLSS has been published on US Topo maps in 11 states (WA, OR, ID, MT, WY, UT, CO, NM, OH, AR, MI). At least four more states (CA, AZ, NV, MO) will be added to this list in 2015. PLSS is also included on Alaska maps. The Bureau of Land Management provides these data, often in cooperation with state agencies. The PLSS layer is turned off by default when a map is opened in Acrobat Reader, and must be clicked on by the user -- the reason is that displaying the PLSS network and the U.S. National Grid together leads to confusing visual clutter.
  • Recreational trails are a harder problem due to the lack of national data sources, but progress is being made here as well. US Topo maps began including the National Scenic Trails (such as the Appalachian Trail) in 2013. The U.S. Fish and Wildlife Service has provided trails for their lands which are now shown on all new US Topo maps. U.S. Forest Service provided trails for their lands in Colorado, and is working on a nation-wide database that will allow us to show trails in all National Forests. In October 2014 we began showing trails contributed by the International Mountain Biking Association (IMBA), a non-government volunteer organization. We expect the number of recreational trails on the maps to steadily increase in the coming years.

 

Tags: Maps, Recreation, Quadrangle, GeoPDF, Scale