This dataset is a continuous parameter grid (CPG) of baseflow index values (percent of discharge as baseflow) estimated at U.S. Geological Survey (USGS) streamgages in the Pacific Northwest. Source data was produced by David Wolock of USGS.

This 1-kilometer raster (grid) dataset for the conterminous United States was created by i nterpolating base-flow index (BFI) values estimated at U.S. Geological Survey (USGS) streamgages. Base flow is the component of streamflow that can be attributed to ground-water discharge into streams.

This dataset is a continuous parameter grid (CPG) of mean slope of upstream stream grid cells in the Pacific Northwest. Source data come from the U.S. Geological Survey National Elevation Dataset and NHDPlus Version 2.

This dataset is a continuous parameter grid (CPG) of mean slope of upstream stream grid cells in the Pacific Northwest. Source data come from the U.S. Geological Survey National Elevation Dataset and NHDPlus Version 2.

This dataset is a continuous parameter grid (CPG) of upstream contributing area data (flow accumulation) in the Pacific Northwest. Source data come from the U.S. Geological Survey National Elevation Dataset and NHDPlus Version 2.

This dataset is a continuous parameter grid (CPG) of mean basin slope in the Pacific Northwest. Source data come from the U.S. Geological Survey National Elevation Dataset and NHDPlus Version 2.

The U.S. Geological Survey’s Water Availability and Use Study Program (WAUSP) (https://water.usgs.gov/ogw/gwrp/activities/regional.html) supports quantitative assessments of groundwater availability in areas of critical importance. As part of a WAUSP study in the arid to semi-arid Northwest Volcanic Aquifer Study Area (NVASA), estimates of runoff and baseflow were determined for 312 streamflow-gaging stations from 1904 to 2015. Gages with complete water years (October to September) of continuous-streamflow record were used to partition streamflow into runoff and baseflow, which is that part of streamflow attributed to groundwater discharge. For each water year annual estimates of baseflow, runoff, and a base-flow index were determined using a series of automated hydrograph separation programs—PART, HYSEP, and BFI. These streamflow-hydrograph analysis methods are available in the U.S. Geological Survey Groundwater Toolbox (https://water.usgs.gov/ogw/gwtoolbox/), which is a graphical, mapping and analysis interface built within an open-source MapWindow geography information system in a Windows computing environment.

The U.S. Geological Survey’s Water Availability and Use Study Program (WAUSP) (https://water.usgs.gov/ogw/gwrp/activities/regional.html) supports quantitative assessments of groundwater availability in areas of critical importance. As part of a WAUSP study in the arid to semi-arid Northwest Volcanic Aquifer Study Area (NVASA), estimates of runoff and baseflow were determined for 312 streamflow-gaging stations from 1904 to 2015. Gages with complete water years (October to September) of continuous-streamflow record were used to partition streamflow into runoff and baseflow, which is that part of streamflow attributed to groundwater discharge. For each water year annual estimates of baseflow, runoff, and a base-flow index were determined using a series of automated hydrograph separation programs—PART, HYSEP, and BFI. These streamflow-hydrograph analysis methods are available in the U.S. Geological Survey Groundwater Toolbox (https://water.usgs.gov/ogw/gwtoolbox/), which is a graphical, mapping and analysis interface built within an open-source MapWindow geography information system in a Windows computing environment.

The U.S. Geological Survey’s Water Availability and Use Study Program (WAUSP) (https://water.usgs.gov/ogw/gwrp/activities/regional.html) supports quantitative assessments of groundwater availability in areas of critical importance. As part of a WAUSP study in the arid to semi-arid Northwest Volcanic Aquifer Study Area (NVASA), estimates of runoff and baseflow were determined for 312 streamflow-gaging stations from 1904 to 2015. Gages with complete water years (October to September) of continuous-streamflow record were used to partition streamflow into runoff and baseflow, which is that part of streamflow attributed to groundwater discharge. For each water year annual estimates of baseflow, runoff, and a base-flow index were determined using a series of automated hydrograph separation programs—PART, HYSEP, and BFI. These streamflow-hydrograph analysis methods are available in the U.S. Geological Survey Groundwater Toolbox (https://water.usgs.gov/ogw/gwtoolbox/), which is a graphical, mapping and analysis interface built within an open-source MapWindow geography information system in a Windows computing environment.

The U.S. Geological Survey’s Water Availability and Use Study Program (WAUSP) (https://water.usgs.gov/ogw/gwrp/activities/regional.html) supports quantitative assessments of groundwater availability in areas of critical importance. As part of a WAUSP study in the arid to semi-arid Northwest Volcanic Aquifer Study Area (NVASA), estimates of runoff and baseflow were determined for 312 streamflow-gaging stations from 1904 to 2015. Gages with complete water years (October to September) of continuous-streamflow record were used to partition streamflow into runoff and baseflow, which is that part of streamflow attributed to groundwater discharge. For each water year annual estimates of baseflow, runoff, and a base-flow index were determined using a series of automated hydrograph separation programs—PART, HYSEP, and BFI. These streamflow-hydrograph analysis methods are available in the U.S. Geological Survey Groundwater Toolbox (https://water.usgs.gov/ogw/gwtoolbox/), which is a graphical, mapping and analysis interface built within an open-source MapWindow geography information system in a Windows computing environment.