The USGS National Water Census (NWC) is designed to systematically provide information that will allow resource managers to assess the supply, use, and availability of the Nation’s water. The goal of the NWC is to provide nationally-consistent base layers of well-documented data that account for water availability and use nationally.
The Water Availability and Use Science Program (WAUSP) supports this goal through work to understand and quantify the inputs, outputs, and changes in the water budget. The primary building blocks of the water budget are base layers of precipitation, streamflow, evapotranspiration (ET), water use, and change in groundwater storage. Measurements or estimates of water budget components provide a means for decision makers to evaluate the water available for human and ecological needs as well as where stresses to the budget exist or may develop. Ideally, the WAUSP seeks to provide estimates of selected water budget components that are compiled via the National Water Census at consistent spatial and temporal scales. Through development of advanced techniques and new accounting methods for the NWC components, the WAUSP strives to provide resource managers with more accurate and finer scale information to support near-real time, local management decisions related to water availability and use.
Collaboration is a critical part of the USGS National Water Census. It not only helps direct USGS efforts towards assessments that are most useful for end users – such as other Federal, State, regional, local, and tribal resource managers, but it also ensures that information produced by the USGS can be aggregated and assimilated with other types of physical, social, economic, and environmental data that affect water availability and use.
Read the report: Continuing Progress Toward a National Assessment of Water Availability and Use
Streamflow • Groundwater • Water Use • Environmental Flows • Evapotranspiration • Focus Area Studies
Below are science components of the National Water Census.
National Water Census: Streamflow
National Water Census: Groundwater
National Water Census: Water Use
National Water Census: Environmental Flows
National Water Census: Evapotranspiration
National Water Census: Focus Area Studies
- Overview
The USGS National Water Census (NWC) is designed to systematically provide information that will allow resource managers to assess the supply, use, and availability of the Nation’s water. The goal of the NWC is to provide nationally-consistent base layers of well-documented data that account for water availability and use nationally.
Sources/Usage: Public Domain.Components of a simple water budget for part of a watershed. The Water Availability and Use Science Program (WAUSP) supports this goal through work to understand and quantify the inputs, outputs, and changes in the water budget. The primary building blocks of the water budget are base layers of precipitation, streamflow, evapotranspiration (ET), water use, and change in groundwater storage. Measurements or estimates of water budget components provide a means for decision makers to evaluate the water available for human and ecological needs as well as where stresses to the budget exist or may develop. Ideally, the WAUSP seeks to provide estimates of selected water budget components that are compiled via the National Water Census at consistent spatial and temporal scales. Through development of advanced techniques and new accounting methods for the NWC components, the WAUSP strives to provide resource managers with more accurate and finer scale information to support near-real time, local management decisions related to water availability and use.
Collaboration is a critical part of the USGS National Water Census. It not only helps direct USGS efforts towards assessments that are most useful for end users – such as other Federal, State, regional, local, and tribal resource managers, but it also ensures that information produced by the USGS can be aggregated and assimilated with other types of physical, social, economic, and environmental data that affect water availability and use.
Read the report: Continuing Progress Toward a National Assessment of Water Availability and Use
Streamflow • Groundwater • Water Use • Environmental Flows • Evapotranspiration • Focus Area Studies
Sources/Usage: Public Domain.
Sources/Usage: Public Domain.
Sources/Usage: Public Domain.
Sources/Usage: Public Domain.
Sources/Usage: Public Domain.
Sources/Usage: Public Domain. - Science
Below are science components of the National Water Census.
National Water Census: Streamflow
The USGS National Water Census complements the USGS national network of more than 8,000 streamgages by estimating streamflow for ungaged locations throughout the country, by analyzing streamflow records, and by providing tools for analysis of streamgage data to end users. The USGS National Water Information System (NWIS) makes the actual streamgage data available to the public, most of it in "near...National Water Census: Groundwater
The National Water Census (NWC) is leveraging a long history of groundwater studies and is accelerating ongoing regional studies to assess the Nation's groundwater reserves, studies that formerly were conducted under the USGS Groundwater Resources Program. The NWC is also increasing the ability to integrate groundwater and surface-water analyses into watershed-level assessments of water...National Water Census: Water Use
Through the National Water Census, USGS will provide national information on withdrawal, conveyance, consumptive use, and return flow by water-use category at spatial and temporal resolutions important for risk-informed water management decisions. Water-use data provide a foundation for water managers to analyze trends over time, plan more strategically, identify, and ultimately quantify...National Water Census: Environmental Flows
Environmental water studies refer to understanding the quantity, timing, and quality of water flows, as well as the water levels and storage required to sustain freshwater and estuarine ecosystems and the human livelihoods that depend on these ecosystems. The concept of ‘environmental flows’ in stream ecology are the basis of these studies, but they go beyond the understanding of surface flows and...National Water Census: Evapotranspiration
No water budget would be complete without accounting for evaporation and related processes, such as transpiration and sublimation. Evapotranspiration, or "ET," refers to the combined flux of plant transpiration and evaporation from the adjacent soil. It is especially important for understanding water used by irrigated crops, and is related to crop productivity. Consumptive water use for irrigation...National Water Census: Focus Area Studies
Focus Area Studies are stakeholder-driven assessments of water availability in river basins with known or potential conflict. They contribute toward ongoing assessments of water availability in large watersheds, provide opportunities to test and improve approaches to water availability assessment, and inform and ground truth the National Water Census with local information. Common to each of the... - Publications
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