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.
National Water Census • Colorado River Basin • Evapotranspiration • Snowpack • Water Use • Groundwater Discharge
Historically, management of water resources in the Colorado River Basin has focused on surface-water supplies; however, groundwater and surface water are interconnected, and groundwater discharge to streams sustains surface-water flows in much of the Upper Colorado River Basin (UCRB). To better understand the link between groundwater and surface water in the basin, the USGS, as part of the Colorado River Basin FAS, has quantified groundwater discharge to streams across the UCRB.
To estimate groundwater discharge to streams in the UCRB, methods were developed to use in-stream water-quality data, specifically the electrical conductivity (specific conductance) of stream water, to quantify the fraction of streamflow that originates as groundwater. For sites where only occasional measurements of specific conductance (referred to as discrete data) have been made, an additional method was developed to estimate the percentage of streamflow that originates as groundwater.
Key Findings and Results
- Groundwater discharge to streams contributes an average of 48 percent of total streamflow in the Upper Colorado River Basin at 229 gaged sites in the basin.
- Spatially, groundwater discharge to streams is greater in upland, mountainous areas that have greater precipitation.
- Read the report
National Water Census • Colorado River Basin • Evapotranspiration • Snowpack • Water Use • Groundwater Discharge
Below are related science components of the Colorado River Basin Focus Area Study.
Colorado River Basin Focus Area Study
Colorado River Basin Focus Area Study: Evapotranspiration
Colorado River Basin Focus Area Study: Snowpack Hydrodynamics
Colorado River Basin Focus Area Study: Water Use
- Overview
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.
National Water Census • Colorado River Basin • Evapotranspiration • Snowpack • Water Use • Groundwater Discharge
Historically, management of water resources in the Colorado River Basin has focused on surface-water supplies; however, groundwater and surface water are interconnected, and groundwater discharge to streams sustains surface-water flows in much of the Upper Colorado River Basin (UCRB). To better understand the link between groundwater and surface water in the basin, the USGS, as part of the Colorado River Basin FAS, has quantified groundwater discharge to streams across the UCRB.
To estimate groundwater discharge to streams in the UCRB, methods were developed to use in-stream water-quality data, specifically the electrical conductivity (specific conductance) of stream water, to quantify the fraction of streamflow that originates as groundwater. For sites where only occasional measurements of specific conductance (referred to as discrete data) have been made, an additional method was developed to estimate the percentage of streamflow that originates as groundwater.
Sources/Usage: Public Domain.Estimates of groundwater discharge to streams (baseflow) at 229 sites in the Upper Colorado River Basin. Groundwater discharge to streams contributes an average of 48 percent of total streamflow in the UCRB. Key Findings and Results
- Groundwater discharge to streams contributes an average of 48 percent of total streamflow in the Upper Colorado River Basin at 229 gaged sites in the basin.
- Spatially, groundwater discharge to streams is greater in upland, mountainous areas that have greater precipitation.
- Read the report
National Water Census • Colorado River Basin • Evapotranspiration • Snowpack • Water Use • Groundwater Discharge
- Science
Below are related science components of the Colorado River Basin Focus Area Study.
Colorado River Basin Focus Area Study
As one of several Focus Area Studies within the USGS National Water Census (NWC), the USGS has completed a 3-year study of water availability and use in the Colorado River Basin.Colorado River Basin Focus Area Study: Evapotranspiration
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.Colorado River Basin Focus Area Study: Snowpack Hydrodynamics
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.Colorado River Basin Focus Area Study: Water Use
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. - Publications