Smart Consultation That Moves Environmental Sciences Forward

Efficient, Science-Driven Solutions for North America's Diverse Aquatic Ecosystems

Consult with an Expert

Trusted Science for Tough Environmental Challenges

Thomas Gast & Associates Environmental Consultants (TGAEC) is a federally and California State registered Small Business specializing in fisheries investigations, particularly instream flow studies, hydrology, and stream restoration. 

Additional services include:

  • Construction monitoring
  • Wildlife surveys
  • Bird presence and absence surveys
  • Habitat mapping
  • Wetland delineation and assessment
  • Hydroacoustic monitoring
  • Fish population assessment and monitoring
  • Fish tagging studies
  • Hydraulic habitat modeling
  • Impact analysis
  • Flow measurements, including acoustic doppler current profiler (ADCP) measurements
  • Water quality monitoring
  • Endangered species act consultation
  • Bathymetry mapping
  • Boat support
  • Habitat Restoration

Let us be your problem-solvers!

Discover Who We Are

Innovative Science

We apply clear, defensible science to support sound decisions. Our work blends field expertise, geospatial analysis, and practical data tools to guide permitting, impact assessment, and resource management. The result is reliable information you can use to move projects forward.

Fisheries and Restoration

We deliver focused fisheries services, including baseline studies, habitat evaluations, population analyses, and restoration planning. Our team supports projects from early design through implementation and performance monitoring, ensuring that ecological goals are met efficiently and effectively.
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