Tetra Tech began in 1966 as a water management consultancy in Pasadena, California, created by engineers focused on coastal projects. The company expanded its services through strategic acquisitions while maintaining its core water expertise. Today it operates through government and commercial divisions providing consulting and engineering for environmental, infrastructure, and resource management projects globally. Tetra Tech emphasizes science-driven solutions for complex challenges in water systems, sustainable infrastructure, and ecosystems. The firm serves both public and private sector clients with a broad range of technical services.