The National Geospatial Program’s Alaska Mapping Initiative
By Tracy Fuller and Michael J. Cooley
Figure 1. US Topo production plan.
The U.S. Geological Survey (USGS) National Geospatial Program (NGP) is launching a multi-year initiative to improve statewide mapping for Alaska that is commensurate with the quality of mapping across the rest of the Nation. The current statewide base map for Alaska was created around 1960 and at a lower resolution than the maps made over the conterminous United States. Improved data holdings for Alaska are required to meet the needs of current applications in safety, planning, research, and resource management. NGP is working closely with multiple State and Federal partners to acquire and enhance the required map data.
The new digital map data will be viewable on The National Map Viewer and will be made available for download by the public for use in their Geospatial Information Systems. The improved data will also be used to produce 1:25,000-scale US Topo maps statewide over Alaska to replace the 1:63,360-scale maps produced nearly 50 years ago. In 2012, the USGS demonstrated several prototype maps and gathered user input to guide the design of the new product. Based on user feedback, the new maps will be produced only where new satellite imagery and new radar elevation data are available to support the project. Availability of these two layers determines the number of maps that can be produced during any one year.
Figure 2. Five-meter IfSAR elevation status.
In FY 2013, the USGS will produce approximately 400 maps that have the required elevation and imagery layers. Another 675 maps will be produced in FY 2014. Figure 1 displays the quadrangles planned for production in FY 2013 and FY 2014. Availability of these two foundational layers is expected to increase in the future, and NGP will increase map production accordingly. It is anticipated that it will take approximately 6 years to acquire the data and to complete the 11,273 maps that cover Alaska at this scale.
To make the Alaska maps, the USGS will use the best available source data to improve its data holdings. The satellite imagery comes to us from the State of Alaska, which contracted to obtain SPOT Image 2.5-meter resolution natural color imagery statewide by 2014, and the USGS purchased an expansion of the Alaska license to display the imagery on the US Topo map product. The elevation data is 5-meter resolution Interferometric Synthetic Aperture Radar (IfSAR) data; the USGS is contracting to acquire IfSAR using funds from multiple State and Federal partners. Elevation data are being collected as funding is made available. Thirty-one percent of the State has been collected to date, and another 10 percent is expected to be collected in the summer of 2013, with hopes of completing statewide IfSAR collection by 2016. Figure 2 shows IfSAR data collected through the summer of 2012.
Surface water features, or hydrography, will come from NGP’s National Hydrography Dataset (NHD). The NHD over Alaska was originally created from the 1:63,360-scale map series. At a minimum, the USGS will update the existing features to meet the same minimum correction specifications that are used in the conterminous United States. Some local partners are working to improve the hydrography data over their critical lands to meet an even higher standard. Glacier information will be updated using Randolph Glacier Inventory data. Where it exists, National Oceanic and Atmospheric Administration shoreline data will be integrated into the NHD to improve shoreline representation.
Figure 3. Advance copy of US Topo sample over Fairbanks, Alaska.
Multiple State and Federal agencies are improving their boundary data for the maps, which will show local, State, Federal, and international boundaries. Structures that will be shown on the maps include police stations, fire stations, post offices, schools, and prisons. These features have been reviewed and updated using publicly available source information. Roads on the maps will come from a commercial vendor. Names on the maps will come from the USGS Geospatial Names Information System (GNIS) database. Alaska US Topo maps will offer a shaded relief layer and include protracted Public Land Survey System data from the Bureau of Land Management.
An effort of this magnitude requires a great deal of skilled collaboration and coordination across multiple levels of government. State efforts are being coordinated through Alaska’s Statewide Digital Mapping Initiative (SDMI), a cooperative program endorsed by the Governor of Alaska and implemented across six Alaska Departments and the University of Alaska. Federal efforts are coordinated through the Alaska Mapping Executive Committee (AMEC), which is co-chaired by the Department of the Interior’s Assistant Secretary for Water and Science and the Acting Deputy Undersecretary of Defense for Installations and Environment. Executive level managers from 15 Federal agencies serve on the Executive Committee, along with Alaska’s Lieutenant Governor and other State agency representatives. SDMI and AMEC work together to ensure that State and Federal activities are cross-coordinated to avoid duplication of effort and to help ensure a unified approach to data acquisition and enhancement.
Readers are invited to view and download several advance production copies of the new maps. US Topo map quadrangles are constructed in digital PDF format with geospatial extensions (GeoPDF™) for viewing on a computer or mobile device. The new satellite image forms a visual base. Users can turn this and other data layers on or off as needed; zoom in and out to highlight specific features or to see a broader context; and print the maps, in their entirety or in customized sections, on a wide variety of plotting devices. The sample maps are available at http://nationalmap.gov/ustopo/alaska/index_2013.html. Figure 3 displays a thumbnail sketch of a 1:25,000-scale US Topo advance copy that can be downloaded from the provided link.