NGP User Engagement Office

Alaska Mapping Initiative

The Alaska Mapping Initiative supports acquisition of new topographic map data and maps for Alaska. The new data and maps raise the accuracy of Alaska topographic mapping to levels found common in the conterminous United States.

New Elevation Data Acquired Statewide for Alaska

In 2011 the Alaska Congressional Delegation requested federal support in modernizing Alaska map data. Collection of a 5-meter resolution elevation grid for Alaska began in 2012, replacing the former 60-meter statewide elevation grid. Radar technology called IfSAR (Interferometric Synthetic Aperture Radar) was used to collect the data because it can penetrate the clouds, smoke, and haze often present in Alaska. Statewide airborne IfSAR collection was completed in 2020 and all data are now processed and available for download. The data are free to the public for any use. Alaska IfSAR acquisition supports the broader national 3D Elevation Program.

 

                                                Status of Alaska IfSAR Elevation Acquisition

Alaska IfSAR Status 2021

5-meter resolution IfSAR elevation data collected statewide for Alaska from 2012 to 2019 is available for download.

(Credit: Tracy Fuller, U.S. Geological Survey. Public domain.)

A New Digital US Topo Map Series Is Being Created Statewide for Alaska

'US Topo' is a digital topographic map format produced by USGS. 11,278 US Topo maps of Alaska will be created and published by USGS to provide statewide coverage of this new map series at 1:25,000 map scale. Each map is created using new contours generated from the new IfSAR elevation data. The maps are distributed for free download and use in a convenient PDF format that can be viewed on a computer or mobile device, or printed to paper. 

                                                       Status of Alaska US Topo Map Production

Alaska US Topo Map Status February 2021

This graphic illustrates the completion status in February 2021 of the first round of 1:25,000-scale US Topo maps of Alaska generated by the USGS National Geospatial Program.

(Credit: Tracy Fuller, USGS. Public domain.)

Downloading Alaska IfSAR Data

Two convenient online portals are available for downloading Alaska IfSAR data. The State of Alaska offers 5-meter IfSAR by tiles for the entire State through their elevation portal found at https://elevation.alaska.gov/. USGS offers the 5-meter IfSAR data tiles, and also provides seamless post-processed elevation data at approximately 10-meter, 30-meter, and 60-meter post spacing. Coverage is currently available for all of Alaska except Kodiak Island and the western Aleutian Islands, which are expected to be available by May 2021. These data can be found at https://viewer.nationalmap.gov/basic/. Bulk download is also available from USGS, and instructions can be found at https://viewer.nationalmap.gov/uget-instructions/index.html.

Downloading US Topo Maps

Alaska US Topo maps are available for free download at https://viewer.nationalmap.gov/basic/. Paper copies can be ordered for a fee from the USGS store located online at https://store.usgs.gov/map-locator.

Terrestrial Hydrography Updates

USGS is supporting update of terrestrial hydrography data (surface water, such as lakes and rivers) for Alaska. The National Hydrography Dataset (NHD), the Watershed Boundary Dataset (WBD), and NHDPlus High Resolution (NHDPlus HR) for Alaska are being updated through collaborative Federal and State partnerships to meet accuracy and content specifications suitable for 1:24,000-scale mapping. Hydrographic features and watershed boundaries are being derived from the Alaska IfSAR elevation data using Elevation-derived Hydrography (EDH) methodology. Upon EDH update, the NHD and WBD data are used to create important watershed characteristic data delivered via NHDPlus HR. These efforts will eventually support the development of an operational National Water Model for Alaska. The Cook Inlet and Matanuska-Susitna (Mat-Su) watersheds are updated through NHDPlus HR, and NHDPlus HR for the Copper River watershed is in development. EDH editing is ongoing for an additional 50,000 square miles in Alaska, primarily on the North Slope and southcentral Alaska. Starting in 2022, USGS and its partners plan to update approximately 65,000 square miles annually until the statewide hydrography update is complete in 2029.

Alask Mat-su Watershed Relief and Hydrography

This graphic shows the extent of the Mat-Su Watershed and displays the terrain and hydrography of the basin.

(Credit: Kacy Krieger, University of Alaska Anchorage. Public domain.)

 

 

Contacts

Tracy Joe Fuller

Alaska Mapping Program Manager & UE Elevation Focus Area Coordinator
NGP User Engagement Office
Phone: 303-601-7652

Brian Wright

National Map Liaison AK
NGP User Engagement Office
Phone: 907-201-0113