Adjudication Support for an Industrial Client

M&A has provided hydrogeologic services for this now-closed facility for over 25 years. These services have included monitoring and modeling to assess the relationship between groundwater and surface water, as well as reviewing legal and technical documents developed by the adjudication court and various stakeholders.


Located near a perennial-to-intermittent river reach, the water supply for this facility was previously pumped from production wells completed in deep basin-fill sediments that could meet peak demands exceeding 16,000 AF/yr. Today, the wells supply water for limited municipal uses.


Adjudication & Water Rights Support

  • Reviewed legal and technical documents prepared by the adjudication court and stakeholder experts to evaluate evolving definitions and approaches for distinguishing surface water and groundwater and characterizing associated impacts
  • Prepared expert reports and provided expert testimony regarding the technical criteria to be used for delineating subsurface water that is legally deemed to be surface water
  • Monitored streamflow and vegetation via visual inspection, automated cameras, and satellite imagery, focusing on a 6-mile perennial-to-intermittent reach adjacent to the wellfield
  • Analyzed geologic, precipitation, streamflow, groundwater withdrawal, water level, and geochemical data to evaluate the relationship between groundwater pumping and surface water flows
  • Interfaced with field biologists and conservation groups to support the evaluation of streamflow and riparian ecosystems
  • Designed and oversaw the installation of a monitoring well network
  • Designed a monitoring program to characterize water sources / types and assess the hydraulic connection between aquifer zones

Groundwater Modeling

  • Developed a groundwater flow model to project the long-term drawdown response to pumping in the deeper basin-fill aquifer on the shallow alluvial system
  • Integrated long-term monitoring and hydrogeologic data into the model
  • Evaluated and updated transport projections to improve the site conceptual model

Water Resource Economics

  • Developed an economic analysis to assess the impact of potential surface water reductions on a downstream agricultural user with senior surface-water rights
  • Used the results of this evaluation to conclude a reduced risk from potential adjudication claims