A Resource for the Protected Areas Database of the United States (PAD-US)



The USGS Protected Areas Database of the U.S. (PAD-US) is the official GIS-based national inventory of protected area boundaries within the U.S. It includes public lands and parks, Wilderness Areas, National Wildlife Refuges, reserves, conservation easements, Marine Protected Areas, and more.

The vision for PAD-US is that it be a single, regularly updated geospatial database that allows users to find the boundaries and essential attribute information for every public park and other protected area in the United States.

PAD-US is published by USGS in collaboration with Boise State University and through coordination with many Federal, State, and non-governmental organization data-stewards.

PAD-US serves as a data coordination, gathering, and integration framework that synthesizes Federal agency data. It also encourages the development of comprehensive, standardized inventories by State data-stewards. PAD-US also has collaborative relationships with other governmental and nonprofit gatherers of related data.

PAD-US is unique because it is:

  • Comprehensive — It is based on the goal of inventorying  all public land and other protected areas, covering everything from small neighborhood parks to huge Wilderness Areas, land trust preserves, easements, and Marine Protected Areas.
  • Publicly available — PAD-US is published by the Federal government; it is open and free to use for all public and commercial applications and research purposes.
  • ValidatedThe PAD-US Data Manual has developed over time through rigorous peer and other review and testing by data-stewards across jurisdictions. For more information, see the PAD-US Data Manual.
  • Authoritative — PAD-US is the official inventory of America’s protected areas – a National Geospatial Data Asset, aggregated from authoritative data sources.
  • Adaptable — PAD-US is designed to support a wide range of uses, not just a specific type of use.
  • Expected — Having a single, federally led source of information on public parks and open space lands makes it intuitive to look for these national data.
  • Collaboratively developed  — PAD-US uses a process based on partnerships with Federal agencies and affiliations with key groups in each State plus national nonprofits and other organizations.

All of this makes PAD-US an outstanding data resource for many different users to apply to research, land management, policy analysis and development, service targeting, and more.


What’s new in PAD-US 2.1

PAD-US 2.1 was completed in September 2020 and focused on completing the PAD-US Inventory and maintaining federal land updates:

  • Integration of over 75,000 city parks in all 50 States (and the District of Columbia) from The Trust for Public Land’s (TPL) ParkServe data development initiative (https://parkserve.tpl.org/) added nearly 2.7 million acres of protected area and significantly reduced the primary known data gap in previous PAD-US versions (local government lands).
  • First-time integration of the Census American Indian/Alaskan Native Areas (AIA) dataset (https://www2.census.gov/geo/tiger/TIGER2019/AIANNH) representing the boundaries for federally recognized American Indian reservations and off-reservation trust lands across the nation (as of January 1, 2020, as reported by the federally recognized tribal governments through the Census Bureau’s Boundary and Annexation Survey) addressed another major PAD-US data gap.
  • Aggregation of nearly 5,000 protected areas owned by local land trusts in 13 states, aggregated by Ducks Unlimited through data calls for easements to update the National Conservation Easement Database (https://www.conservationeasement.us/), increased PAD-US protected areas by over 350,000 acres.
  • Major update of the Federal estate (fee ownership parcels, easement interest, and management designations), including authoritative data from 8 agencies: Bureau of Land Management (BLM), U.S. Census Bureau (Census), Department of Defense (DOD), U.S. Fish and Wildlife Service (FWS), National Park Service (NPS), Natural Resources Conservation Service (NRCS), U.S. Forest Service (USFS), National Oceanic and Atmospheric Administration (NOAA).  The federal theme in PAD-US is developed in close collaboration with the Federal Geographic Data Committee (FGDC) Federal Lands Working Group (FLWG, https://communities.geoplatform.gov/ngda-govunits/federal-lands-workgroup/).
  • Complete National Marine Protected Areas (MPA) update: from the National Oceanic and Atmospheric Administration (NOAA) MPA Inventory, including conservation measure (‘GAP Status Code’, ‘IUCN Category’) review by NOAA.

See the USGS PAD-US website for update history: https://www.usgs.gov/core-science-systems/science-analytics-and-synthesis/gap/pad-us-data-history

Status of Data Completeness

Updates to PAD-US include the most up-to-date aggregation of Federal lands and waters, National Conservation Easement Database (NCED) easement data, and State updates from those states with capacity to provide new data.

Current measures of the estimated completeness of all data in PAD-US can be found on the Data Stewards page – this also includes individual estimates for Federal, State, local and nonprofit fee owned lands. Go to the National Conservation Easement Database website for easement inventory completeness.

PAD-US 2.1 is the most complete protected areas inventory available with most federal, state, and local government lands (thanks to the Trust for Public Land’s ParkServe project); however, Tribal lands are not well represented and data gaps occur below the state level (e.g. county parks, local land trust preserves).  Fortunately, initiatives are underway to continually improve inventory completeness.

A detailed summary of the state of PAD-US data completeness is shown below, last updated in February 2021. Watch for updates to this document on the Federal Lands Workgroup page