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Fall 2002
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The National Map From the USGS

Digital geographic information is vital for an economically healthy and secure America. This fact is not new to GIS practitioners. One of the most used and well-known map series, the U.S. Geological Survey (USGS) Quad, is about to enter a modernization program that will greatly benefit not only the GIS community but the nation itself.

The United States invested approximately $1.6 billion and 33 million person-hours in the existing topographic map series over the past century. Topographic mapping includes both the natural (terrain, streams, wetlands, etc.) and human (buildings, roads, pipelines, power lines, cadastral boundaries, etc.) environment. These maps and the associated digital data derived from them in the past quarter century represent our most extensive geographic data infrastructure. It is very clear, however, that this critical asset is becoming increasingly outdated as its existing and potential utility is increasing at a rapid pace.

Existing topographic maps range in age from one to 57 years. The average age of the 55,000 maps in the series is 23 years. Many maps have never been updated, and adjacent maps are sometimes more than a decade apart.

January 2001 marked the beginning of a decade-long effort by the USGS, which is part of the Department of Interior, to transform the Quad paper series into a seamless, integrated, and online database known as The National Map. This strategic project requires extensive partnerships with state and local governments, other federal agencies, nongovernmental organizations (NGOs), universities, and the private sector. These alliances are being forged to construct The National Map.

The concept of a national map implies that this is not just a project of the federal government but is truly a national effort that will be available to, and used by, every sector of the national economy. The project will build in the vertical integration of geographic information from all levels of government. It will leverage limited resources to fulfill the geospatial community's motto of "collect once, use many times."

The National Map will improve performance, lower costs, and reduce the redundancy of geographic development by different agencies and levels of government. It will vastly improve citizen access to current geography information and will finally unleash the integrating power of digital maps.

The United Kingdom realized great savings from investments in modernized digital mapping infrastructure. The return on investment (ROI) from improvements in access to and use of digital geographic data was in the neighborhood of $10 to $15 for every dollar invested.

In "The State of GIS in the Government," a 1995 Department of Interior internal report on the benefits of digital geographic data and geographic information systems, it was estimated that electronic mapping was 80 percent less costly to produce and maintain than comparable paper maps.

Digital spatial data is essential to almost all sectors of the national economy. The private sector needs current and accurate digital geographic data that will be provided by The National Map. Examples include

  • Road and highway files used for fleet vehicle routing by trucking companies, home delivery by retailers, and location-based services by all types of Businesses
  • Digital elevation data for cellular telephone tower siting, airline and general aviation flight path planning, and brush and forest fire spread modeling for insurance companies
  • Topographic data for private utility power line and pipeline maintenance, planning, and routing
  • Detailed geologic and topographic data for mining and energy exploration and extraction

A number of additional data layers that are vital to the private sector will be built upon The National Map foundation. For example, the floodplain maps produced by the Federal Emergency Management Agency (FEMA) are directly based on the digital elevation data created by the topographic map series from the USGS. Insurance companies use the floodplain plus topographic data for insurance underwriting. Banks must include a floodplain data marker for every building mortgage they fund. The initiative of the U.S. Department of Agriculture (USDA) to create a national spatial database of agricultural units (essentially individually cultivated fields) will yield immense benefits to the private agriculture and crop insurance sectors. These agricultural units need The National Map as a basemap. Census geographic and associated demographic data for retail site selection and market area planning is also tied to a national basemap.

Because of its integration capacity, digital maps and GIS have become an integral part of the infrastructure of thousands of government agencies throughout the United States. Virtually all state and local agencies use geographic data in which they have invested tens of millions of dollars. This digital data is used in areas such as transportation planning, parks and recreation management, open space protection, HazMat cleanup, public health epidemiology, water and wastewater management, social services delivery, and emergency response. Examples include

  • Surveyed digital property ownership and cadastre records are the financial foundation (property taxes) for local government and school districts in much of the nation.
  • School districts use street data for school bus routing.
  • Public health agencies have leveraged geographic data in response to the West Nile virus and other diseases.
  • State legislatures require underlying geographic data for redistricting.

On September 11, 2001, the mission-critical role of geographic data and geographic information systems was demonstrated. The USGS provided more than 120,000 maps, hundreds of digital files, and Landsat images to assist with disaster planning, prevention, mitigation, and response efforts conducted at the local, state, and federal levels.

Digital geographic data will support the successful implementation of four specific policy initiatives outlined in the U.S. 2003 Homeland Security Budget:

  • Supporting first responders
  • Defending against bioterrorism
  • Securing America's borders
  • Using twenty-first century technology to secure the homeland

In addition, digital geographic data is critical in support of detecting weapons of mass destruction, infrastructure protection, and continuity of government operations. The National Map's topographic maps will be the only coast-to-coast, border-to-border coverage of our nation's critical infrastructure.

The call by President Bush in the White House publication "Securing the Homeland, Strengthening the Nation" for a homeland security strategy based on the principles of partnership with state and local governments, the private sector, and citizens is supported by The National Map.

Leveraging the nation's geographic data and the half million users of GIS in the United States will be a key function of The National Map. The goals of the President's Management Agenda Fiscal Year 2002 for expanded electronic government designed to serve citizens' needs, break down obsolete bureaucratic divisions, and create easy-to-find single points of access to government information are the guiding principles of The National Map.

The National Map will be the foundation for a modern geographic data infrastructure for our nation.

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