Water Availability and Use Science Program
Science and Products
The USGS Integrated Water Availability Assessments (IWAAs) are a multi-extent, stakeholder driven, near real-time census and seasonal prediction of water availability for both human and ecological uses at regional and national extents.
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.
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...
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.
New USGS-developed, remote-sensing based approaches were used to quantify agricultural irrigation water consumption on a field-by-field scale. The work produced the first ever Colorado River Basin-wide, 100-m scale actual ET estimate (2010) using Landsat imagery.
The Focus Area Study examined factors affecting snowpack distribution, snowmelt, and losses of snowpack water due to sublimation in the Upper Colorado River Basin. Also, as part of the FAS, the USGS has developed methods to make physical measurements of snowpack sublimation.
Water-use data were compiled as annual total withdrawals by source and aggregated to 8-digit Hydrologic Unit Code watersheds from 1985 to 2010 in five year intervals. The new compilation allows for an evaluation of water-use trends in the Colorado River Basin and the effect of use on the water budget.
Methods were developed in the CRB FAS to estimate groundwater discharge to streams in the upper Colorado River Basin (UCBR) using in-stream water-quality data. Results indicate groundwater discharge to streams contributes an average of 48 percent of total streamflow in the UCRB.
The Water Availability Tool for Environmental Resources provides a decision support system to examine different land-cover forecasts and climate projections using physical aspects of the basin that will remain unchanged, like topography and soil properties, to estimate streamflow for ungaged streams.
The Delaware River Basin Streamflow Estimator Tool (DRB-SET) uses historical records of streamflow to estimate daily mean streamflow at any stream location within the Delaware River Basin for the period 1960-2010, incorporating basin characteristics such as drainage size, soil, geology, and seasonal precipitation.