Progress Toward a National Water Census

USGS congressional briefing addresses vital uses of comprehensive water information

USGS Water Census

The U.S. Geological Survey (USGS) led a congressional briefing featuring state and regional water stakeholders who spoke about vital uses of comprehensive water information that would be met by the National Water Census called for by the SECURE Water Act of 2009.

Growing populations, increased energy development and the uncertain effects of a changing climate magnify the need for an improved understanding of water use and availability. However, no comprehensive and current national assessment of water resources exists.

A report released in April, "Progress Toward Establishing a National Assessment of Water Availability and Use," fulfilled a requirement under the 2009 law for the Secretary of the Interior to report to Congress on progress made in implementing the national water availability and use assessment program, also referred to as a National Water Census.

A water census is a complex undertaking, which points to why national water availability and use have not been comprehensively assessed in more than 35 years. Since then, competition for water resources has increased greatly and, in addition to human use, considerably more importance is now attached to the availability of water for environmental and ecosystem needs.

USGS envisions the Water Census to be a key ongoing activity that, like the population census mandated by the Constitution, supports national decision-making in many different ways.

The resources currently available for this census are finite, however, USGS foresees that estimates of flow at ungaged locations and estimates of evapotranspiration will be among the earliest products of the National Water Census. Providing complete water use information and adequately assessing the nation’s groundwater resources with respect to water availability will require additional time.

Although the existing data are limited and much work remains to be done, funding over the past two years has allowed important progress. USGS will continue to work with partner agencies and organizations to maximize the utility of the information for a broad range of uses.

The Water Census is part of an overarching Department of the Interior initiative known as WaterSMART (Sustain and Manage America’s Resources for Tomorrow). Through WaterSMART, the department is working to achieve a sustainable water strategy to help meet the nation’s water needs. The Water Census will help inform that strategy.

USGS is developing plans for the Water Census in coordination with other federal and non-federal agencies, universities and other organizations. Collaboration across agency boundaries ensures that information produced by USGS can be aggregated with data on other types of physical, social, economic and environmental factors that affect water availability.