Upper Rio Grande Basin Focus Area Study


Streamflow Processes

Streamflow processes in the URGB will be investigated by 1) estimating the relative contributions of runoff (surface water) and baseflow (groundwater discharge) in streamflow, and 2) evaluating trends in total streamflow and baseflow over time. Recent studies have shown that the timing and availability of spring runoff is changing, which may substantially affect the way surface water has to be managed in the URGB. Recent studies also highlight the importance of baseflow, or groundwater discharge to streams, in sustaining surface water flows. The approach to complete this study component is:


Study Component Lead

Christine Rumsey

USGS Utah Water Science Center

Estimate baseflow with hydrochemical hydrograph separation.

  1. Determine availability of existing data within USGS databases. Data availability will determine the spatial and temporal extent of these analyses.
  2. Apply criteria to discharge and water quality data to ensure that hydrochemical baseflow separation is appropriate for each site.
  3. Use specific conductance data to calculate contribution from baseflow to surface water over time.

Explore drivers in spatial variability of baseflow discharge

  • Statistically relate baseflow estimates to watershed characteristics such as climate, soil, topography, and land cover variables.

Timing and trends analysis

  1. Evaluate and compare annual and seasonal trends in streamflow, baseflow, runoff, and hydrologic partitioning for selected sub-basins.
  2. Compare annual trends in streamflow components to annual trends in precipitation metrics, including annual precipitation, peak snow water equivalent, and snowmelt.