Tetra Tech is a global leader in the technology, engineering, and construction of wastewater solutions. We provide sustainable solutions to our clients, using our strong foundation in science to address regulatory requirements, state-of-the-art technology, and examine financial options.

Tetra Tech’s wastewater treatment specialists combine their expertise in the design and operation of biological and physical and chemical processes to meet our client’s needs for effective, efficient treatment facilities. Our engineers regularly perform hands-on process energy audits, comprehensive performance evaluations, and plant optimization.

We apply our skills to design of nitrification and denitrification processes; enhanced biological phosphorus removal processes; filtration, membrane bioreactor, and other membrane processes for reuse or groundwater replenishment; disinfection and oxidation processes (including chemical and UV); and biosolids processes for stabilization, as well as energy and nutrient recovery.

We work across the treatment spectrum, applying our knowledge of microbiology to design of selectors for control of filamentous organisms in activated sludge processes and our capability with chemical process modeling to design metals precipitation processes for treatment of wastes from mining and other industries. Tetra Tech’s approach includes application of control technology including online instrumentation, SCADA, and advanced control algorithms; and operator training to improve process control capability and reduce operating costs.

Intelligent Master Planning

  • Asset management
  • Facility planning
  • Capital improvement planning
  • Regulatory compliance
  • Sustainability planning

Management Consulting

  • Financial planning and rate studies
  • Security
  • Threat and vulnerability assessments
  • GIS-based maintenance planning

Collection and Transmission

  • Sewer system evaluation surveys
  • Flow monitoring
  • Infiltration and inflow studies
  • Sewer rehabilitation and restoration
  • Large diameter forcemains
  • Lift stations
  • Hydraulic modeling
  • Reclaimed water transmission and distribution
  • Alternative collection systems

Instrumentation and Control Systems

  • Remote status and controls
  • Data management and trending analysis
  • Automated process control strategies

Treatment Facilities

  • Flow equalization
  • Sedimentation
  • Biological nutrient removal
  • Activated sludge
  • Sequencing batch reactors
  • Membrane bioreactors
  • Fixed-film processes
  • Oxidation ditch technology
  • Aerated lagoons
  • Disinfection and dechlorination
  • Nutrient recovery systems
  • Small community and decentralized systems
  • Soil dispersal and aquifer recharge
  • Constructed wetlands
  • Water reclamation
  • Membrane treatment of secondary effluent
  • Process evaluation and optimization

Biosolids and Organics Management

  • Dewatering and thickening
  • Composting and pelletization
  • Incineration and land application
  • Anaerobic and aerobic digestion
  • ATAD
  • Anaerobic digestion and power generation
  • Animal waste management
  • Co-digestion of solid wastes and biosolids

Odor Control

  • Biological
  • Chemical
  • Air ionization

Operations and Training

  • Process control
  • Microbiology
  • Biological nutrient removal
  • Plant optimization
  • Comprehensive performance evaluations
  • Energy efficiency
  • Energy audit and optimization
  • Process troubleshooting

Construction Management

  • Resident engineering services
  • Program management services
  • Owner’s representative services
  • Design-build delivery
  • Construction management at risk delivery
  • Performance testing services
  • Start-up and training services