Tetra Tech’s experts build models based on an in-depth understanding of the fundamental nature of systems, a strong field data collection and interpretation program, and computer-aided geographic mapping and visualization tools.

Modeling is used to simulate changes in our environment. Our expertise in simulating and predicting the behavior of  physical, biological and chemical characteristics within natural and manmade systems provides public and private clients with the data they need to make informed decisions.

Our results help policymakers make informed decisions to address regulatory requirements, human health and environmental concerns, and future planning scenarios. We also use modeling to create visualizations of planned infrastructure such as pipelines and wind towers to help stakeholders understand how the anticipated changes will affect the landscape.

We have been at the forefront of water resources modeling since the 1960s—from the early physical models to the development of  the state-of-the-art modeling system SUSTAIN, which supports users in in selecting the most cost-effective methods for managing runoff in cities. We have applied models across thousands of watersheds, including a range of climate and topographic conditions from swamps to alpine regions.

Tetra Tech conducts air quality and emissions modeling for transportation-related greenhouse gases and criteria. This includes full life-cycle analysis (extraction, production, and use) for each of the conventional and alternative fuel/pathways, technology costs and potential fuel savings, environmental impact and costs, and societal cost analysis to estimate human health impacts.

Our visualization team creates simulations to effectively predict and communicate to regulatory agencies and project stakeholders information about potential changes resulting from a proposed project. We also use these tools to supplement standard visual assessment practices in identifying the potential impacts a project might have on the surrounding visual environment.


  • Hydrologic and hydrodynamic models
  • Two- and three-dimensional hydrodynamic and water quality models
  • Multimedia fate and transport models, including indoor vapor intrusion models
  • Visualization simulation
  • Hazard assessment and mitigation models