This data set provides estimated and measured streamflow data and hydrograph-separation results for five sites located in northwest Mississippi. Streamflow data were collected by the U.S. Geological Survey (USGS) and the U.S. Army Corps of Engineers. Hydrograph-separation results provide runoff and baseflow estimates at each site that were calculated using four methods: PART, HYSEP Fixed, HYSEP Local Minimum, and BFI Standard, as well as an average base flow index (BFI) for all four methods.

These netCDF output files from the Soil-Water-Balance Model contain daily calculations for the Mississippi Embayment Regional Aquifer System model domain of irrigation, net infiltration (recharge), runoff, soil moisture storage, and actual evapotranspiration amounts for the years 2000 to 2018 and gross precipitation as read from DayMet and processed through the USGS Soil-Water-Balance Model v.2.0 (Westenbroek and others, 2018). Input files used in the SWB run included agricultural land use as estimated by Brown and Pervez (2014) and provided by the USDA National Agricultural Statitical Service and soil properties derived from NRCS gSSURGO and STATSGO data (Wieczorek, 2014). Calculations were driven by DayMet version 3 daily precipitation and air temperatures (Thornton and others, 2018). Further details about the generation and application of the data can be found in Open File Report 2021-1008 (https://doi.org/10.3133/ofr20211008). These data are extracted from the model output contained in the companion model archive data release: https://doi.org/10.5066/P98PBR8O.

These netCDF output files from the Soil-Water-Balance Model contain daily calculations for the Mississippi Embayment Regional Aquifer System model domain of irrigation, net infiltration (recharge), runoff, soil moisture storage, and actual evapotranspiration amounts for the years 2000 to 2018 and gross precipitation as read from DayMet and processed through the USGS Soil-Water-Balance Model v.2.0 (Westenbroek and others, 2018). Input files used in the SWB run included agricultural land use as estimated by Brown and Pervez (2014) and provided by the USDA National Agricultural Statitical Service and soil properties derived from NRCS gSSURGO and STATSGO data (Wieczorek, 2014). Calculations were driven by DayMet version 3 daily precipitation and air temperatures (Thornton and others, 2018). Further details about the generation and application of the data can be found in Open File Report 2021-1008 (https://doi.org/10.3133/ofr20211008). These data are extracted from the model output contained in the companion model archive data release: https://doi.org/10.5066/P98PBR8O.

Base flow, the groundwater contribution to streamflow, is beneficial data for analysis of groundwater-flow systems. This data release includes base-flow estimates and streamflow data for 471 Oregon streamgage sites. Categories of data include: (1) site information, (2) water year estimates of base flow and streamflow, and (3) daily estimates of base flow. Water-year base-flow estimates are considered most reliable; daily estimates are provided for completion and summarization purposes only. Daily discharge (streamflow) data from water years 1980–2023 were obtained from the United States Geological Survey (USGS; https://waterdata.usgs.gov) and the Oregon Water Resources Department (OWRD; https://apps.wrd.state.or.us/apps/sw/hydro_report/) online databases and used to estimate base flow using three methods: low-flow, graphical hydrograph separation (GHS), and chemical hydrograph separation (CHS). Specific conductance (SC) data from continuous SC monitoring at streamgages were obtained from the USGS database and used for CHS base-flow analysis at 15 sites. Data are in .csv file and .txt file format.

Understanding how changing climatic conditions affect streamflow volume and timing is critical for effective water management. In the Rio Grande Basin of the southwest U.S., decreasing snowpack, increasing minimum temperatures, and decreasing streamflow have been observed in recent decades, but the effects of hydroclimatic changes on baseflow, or groundwater discharge to streams, have not been investigated. The dataset created in this data release was used to help support a study to determine how trends in precipitation, snowpack accumulation, and snowmelt rate relate to streamflow, baseflow, and the hydrologic partitioning of baseflow and runoff at 12 sites in the Upper Rio Grande Basin (URGB) during 1980 to 2015. Streamflow was partitioned into baseflow and runoff components at a daily time step using conductivity mass balance hydrograph separation. Trends in annual streamflow, baseflow, runoff, baseflow index, precipitation, snowmelt rate, and peak snow water equivalent (SWE) were evaluated from 1980 to 2015 using the non-parametric Mann-Kendall trend test.

Understanding how changing climatic conditions affect streamflow volume and timing is critical for effective water management. In the Rio Grande Basin of the southwest U.S., decreasing snowpack, increasing minimum temperatures, and decreasing streamflow have been observed in recent decades, but the effects of hydroclimatic changes on baseflow, or groundwater discharge to streams, have not been investigated. The dataset created in this data release was used to help support a study to determine how trends in precipitation, snowpack accumulation, and snowmelt rate relate to streamflow, baseflow, and the hydrologic partitioning of baseflow and runoff at 12 sites in the Upper Rio Grande Basin (URGB) during 1980 to 2015. Streamflow was partitioned into baseflow and runoff components at a daily time step using conductivity mass balance hydrograph separation. Trends in annual streamflow, baseflow, runoff, baseflow index, precipitation, snowmelt rate, and peak snow water equivalent (SWE) were evaluated from 1980 to 2015 using the non-parametric Mann-Kendall trend test.

These data include base flow separation estimates for 64 USGS streamflow gages in the Lake Superior watershed from 1945 to 2020, shapefiles of the gaging stations and watersheds for each gaging station, and a zipped folder of graphics of the base flow separation results. The base flow separation estimates were calculated using the U.S. Geological Survey Groundwater Toolbox (Barlow and others, 2014) for any complete water years of record for these gages from 1945 to 2020. The shapefile of the gaging stations includes the starting and ending years of data for each station, the number of years of record. The watersheds shapefile includes the source for the watershed delineation, the watershed area, and the number of upstream and(or) downstream gaging stations on the same river system. If there are upstream gaging stations in the river system, the watershed delineated is only the incremental part of the watershed between gaging stations. The baseflow separation estimates for each gaging station include daily, monthly, and annual output from the Groundwater Toolbox for six estimation methods included in the software (full references are available in Barlow and others, 2014): the baseflow Index-Standard method, HySep Fixed Interval, HySep Local Minimum, HySep Sliding Interval, baseflow Index-Modified, PART, and BFLOW. A summary of the annual baseflow estimates for all the gaging stations using all the methods is provided also is included in this data release. This data release is one of three child items under the overall data release at https://doi.org/10.5066/P9084UKQ.

These data include base flow separation estimates for 64 USGS streamflow gages in the Lake Superior watershed from 1945 to 2020, shapefiles of the gaging stations and watersheds for each gaging station, and a zipped folder of graphics of the base flow separation results. The base flow separation estimates were calculated using the U.S. Geological Survey Groundwater Toolbox (Barlow and others, 2014) for any complete water years of record for these gages from 1945 to 2020. The shapefile of the gaging stations includes the starting and ending years of data for each station, the number of years of record. The watersheds shapefile includes the source for the watershed delineation, the watershed area, and the number of upstream and(or) downstream gaging stations on the same river system. If there are upstream gaging stations in the river system, the watershed delineated is only the incremental part of the watershed between gaging stations. The baseflow separation estimates for each gaging station include daily, monthly, and annual output from the Groundwater Toolbox for six estimation methods included in the software (full references are available in Barlow and others, 2014): the baseflow Index-Standard method, HySep Fixed Interval, HySep Local Minimum, HySep Sliding Interval, baseflow Index-Modified, PART, and BFLOW. A summary of the annual baseflow estimates for all the gaging stations using all the methods is provided also is included in this data release. This data release is one of three child items under the overall data release at https://doi.org/10.5066/P9084UKQ.

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.