Principal Project Engineer Tunnels

We are seeking a Principal Tunnels Engineer to support the design and delivery of major tunneling and underground infrastructure projects, primarily within the transportation sector but also supporting water, energy, and other infrastructure programs. Working from our LA office in a hybrid capacity, this role focuses on technical design leadership, project delivery, and mentoring, working within multidisciplinary teams to deliver safe, innovative, and high‑quality solutions across all phases of project development.

• Deliver technical design and analysis for tunnels and underground structures across concept, preliminary, and detailed design phases.
• Support and contribute to the delivery of large‑scale tunneling and underground infrastructure projects, particularly major transportation programs.
• Provide technical leadership within project teams, resolving complex engineering challenges and ensuring high‑quality outcomes.
• Review and validate engineering calculations, reports, drawings, and specifications to ensure compliance with applicable codes, standards, and best practices.
• Apply advanced engineering tools, software, and methodologies (e.g., PLAXIS, BIM, Civil 3D) to improve design efficiency and project performance.
• Coordinate with multidisciplinary teams, clients, and stakeholders to clarify requirements and deliver practical, cost‑effective solutions.
• Contribute technical input to proposals and bids, supporting business development and project acquisition efforts.
• Mentor and provide technical guidance to junior engineers, supporting capability development and knowledge sharing within the team.
• Stay informed on emerging technologies and industry trends, incorporating innovative approaches where appropriate.
• Lead by example in health, safety, and wellbeing, promoting lessons learned and modeling positive safety behaviors.
• Champion the organization’s values, code of conduct, and inclusion and diversity, fostering a collaborative and inclusive working environment.

• Bachelor’s degree in Civil Engineering or equivalent (Master’s degree preferred).
• Professional Engineer (PE / P.Eng.) license required or ability to obtain within a defined timeframe.
• 15+ years of experience in tunneling, underground structures, or related heavy civil infrastructure projects.
• Proven experience delivering projects across Transportation, Water/Wastewater, Energy, and other infrastructure sectors.
• Strong technical proficiency in tunnel and underground design principles, standards, and methodologies.
• Experience with engineering software and tools such as PLAXIS, SAP
  2000, Strand7, RS2/RS3, AutoCAD Civil 3D, Micro Station, BIM platforms, and related analysis tools.
• Solid understanding of geotechnical, structural, and environmental considerations in underground works.
• Demonstrated ability to lead technical design reviews and manage risk, quality, and technical performance on multidisciplinary projects.
• Strong communication and collaboration skills, with a proven ability to mentor and develop junior engineers.
• Experience supporting project management activities such as scheduling, budgeting, and technical reporting is an asset.

At Mott Mac Donald, our employees have a stake and a voice in our business, providing them with a direct connection to our success through our personal and group performance bonuses. We provide a comprehensive benefit package that includes 401k, medical, dental and vision insurance, short‑term/long‑term disability, paid holidays, PTO, parental leave, and company‑paid life insurance.

The expected salary for this position is $158,000 - $193,000

At Mott Mac Donald, we believe great ideas happen when we’re together. Our hybrid approach centers on an in‑office culture, with most of your time spent collaborating face‑to‑face and a minimum of three days per week in the office. We balance flexibility with connection, so you and your manager can choose how to meet client, team, and personal commitments.

Equal opportunity is the law.

We seek to promote fair employment procedures and practices to ensure equal opportunities for all. We encourage individual expression in our workplace and are committed to creating an inclusive environment where everyone feels they have the opportunity to contribute.

All qualified applicants will receive consideration for employment without regard to race, color, religion, sex, national origin, age, protected veteran status, creed, marital status, sexual orientation, gender identity, citizenship status or disability status.