Water Availability and Use Science Program
Science and Products
Water Availability and Use Science Program: National Water Census
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.
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...
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 more comprehensive reporting of national information on withdrawal, conveyance, consumptive use, and return flow by water-use category. Water-use data enables water managers to plan more strategically and enables the analysis of trends of over time. It is also vital to water-availability studies such as watershed and groundwater models.
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...
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...
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...
National Water Census: Collaboration
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...
Apalachicola-Chattahoochee-Flint River Basin Focus Area Study: Drought Impacts on Streams and Groundwater
During 2011 drought conditions in the ACF basin provided an opportunity to document streamflow and groundwater levels under these extreme conditions. Over 350 water levels were measured in wells and streamflow was measured at 212 streams or springs.
Apalachicola-Chattahoochee-Flint River Basin Focus Area Study: Water Use
Water use estimates and water returns for the ACF Basin were estimated and compiled by category and location during 2010. Categories included public supply, self-suppled domestic, self-supplied commercial, industrial, mining, agricultural (crop irrigation, livestock, and aquaculture), and thermoelectric-power generation. Methods for estimating irrigation water use were compared and evaluated...
Apalachicola-Chattahoochee-Flint River Basin Focus Area Study: Estimating Streamflow
A hydrologic model that simulates streamflow conditions in the ACF Basin was constructed using the Precipitation Runoff Modeling System. The model simulated development by including withdrawals and returns, interbasin transfers, storage in unmanaged reservoirs, and impervious surface.
Apalachicola-Chattahoochee-Flint River Basin Focus Area Study: Groundwater/Surface-Water Interactions
In the lower Chattahoochee and Flint River Basin, a groundwater flow model was developed to simulate the effects of groundwater withdrawals on streamflow. This model was linked with the streamflow model to improve estimates of baseflow conditions during critical times, such as droughts.