Groundwater / Surface Water

Tools for quantifying the impacts of pumping on other water resources


Groundwater pumping — especially large-scale and/or long-term pumping — has the potential to impact springs, lakes, and streams, as well as other water users. It can also create unanticipated adverse water quality effects. Studies to assess pumping impacts can be motivated by a legal claim or permitting requirement.

We characterize the complex hydrologic interactions between groundwater and surface water through monitoring and data collection, data analysis, and modeling. Our field team has experience with a wide range of groundwater and surface water sampling methods and remote sensing tools. We conduct baseline surveys of surface water resources including streams, springs, and seeps and establish monitoring protocols for evaluating impacts from proposed actions. We collect data on groundwater pumping, water level changes, water quality, and aquifer properties to characterize drawdown and water quality impacts on nearby surface water resources. We conduct pumping tests and groundwater modeling to assess the current and future capture of spring flow and/or surface water by pumping, as well as interference effects between pumping centers.

Our field staff members are trained by the nationally recognized Spring Stewardship Institute (SSI), which evaluates springs as ecosystems from hydrologic, geomorphologic, and ecologic perspectives.  Field teams use ruggedized tablets to record data that can be incorporated into our HydroSQL database providing web-based access to all data, photographs, lab results, and timeseries for the project team.


  • Surveying streams, springs, and seeps and other surface water features
  • Monitoring, sampling, and analysis of surface water occurrence in a channel, through field surveys and remote sensing tools
  • Evaluating groundwater pumping impacts on Groundwater Dependent Ecosystems (GDEs) such as rivers, ephemeral washes, and riparian ecosystems
  • Assessing applicability of Waters of the United States (WOTUS) through flow regime characterization and assessing “functional equivalent discharges”
  • Applying statistical tools to evaluate baseflow and distinguish changes to streamflow caused by climatic conditions from those resulting from human activities
  • Technical studies to support the legal distinction between surface water and groundwater (and “subflow” within Arizona)
  • Evaluating depletions of interconnected surface water and establishing sustainability criteria for Groundwater Sustainability Plans (under California’s Sustainable Groundwater Management Act, SGMA)