Mechanical Engineering Senior

At AECOM, we're delivering a better world. Whether improving your commute, keeping the lights on, providing access to clean water, or transforming skylines, our work helps people and communities thrive. We are the world's trusted infrastructure consulting firm, partnering with clients to solve the world’s most complex challenges and build legacies for future generations.

With accelerating infrastructure investment worldwide, our services are in great demand. We invite you to bring your bold ideas and big dreams and become part of a global team of over 50,000 planners, designers, engineers, scientists, digital innovators, program and construction managers and other professionals delivering projects that create a positive and tangible impact around the world.

AECOM is seeking a Senior Mechanical Engineer based in Orange, California. Join our dynamic team supporting exciting projects!Work independently and make technical decisions based on building code interpretation as well as company, client, and industry standard practices. Grow your career with us in our Building+ Places group.

The Senior Mechanical Engineer will be responsible for the following but not limited to;

Design of heating, ventilation and air conditioning systems as well as plumbing systems for large projects federal government, commercial, and institutional facilities

Perform Construction Administration services, including review of shop drawings, RFI’s and review of contractor proposed change orders

Perform site/field visits to ascertain existing conditions including equipment condition evaluations

Organize/plan projects to ensure quality controls and project criteria are met and within budget

Assist with mentoring of junior staff within the Mechanical Department

Review and edit specifications

Interact and work with a diverse set of clients and subcontractors

Serves as lead engineer on mid - to large size projects.

Bachelor’s degree in Mechanical Engineering from an ABET accredited Mechanical Engineering Program

6+ years of experience in mechanical design of HVAC and Plumbing systemsor demonstrated equivalency of experience and/or education

S. citizenship due to federal contract/security requirements

8+ years of experience in mechanical design of HVAC and Plumbing systems

Experience using AutoCAD and Revit

Ability to work on multiple projects at once

Proficient in Building Load Calculation and Energy Modeling

Proficient in the design of plumbing systems including sanitary, storm, and water distribution systems

Healthcare Data Centers / Mission Critical Higher Education Corporate Commercial / Mixed Use Science & Technology (Labs)

To support this commitment, all newly hired employees are required to attend an in-person Day 1 onboarding at an AECOM office location as a condition of employment.

Depending on your employment status, AECOM benefits may include medical, dental, vision, life, AD&D, disability benefits, paid time off, leaves of absences, voluntary benefits, perks, flexible work options,well-being resources, employee assistance program, business travel insurance, service recognition awards, retirement savings plan, and employee stock purchase plan.

As a trusted professional services firm powered by deep technical abilities, we solve our clients’ complex challenges in water, environment, energy, transportation and buildings. Our teams partner with public- and private-sector clients to create innovative, sustainable and resilient solutions throughout the project lifecycle - from advisory, planning, design and engineering to program and construction management. AECOM is a Fortune 500 firm that had revenue of $16.1 billion in fiscal year 2025. Work on groundbreaking projects - both in your local community and on a global scale - that are transforming our industry and shaping the future. With cutting-edge technology and a network of experts, you’ll have the resources to make a real impact. Our award-winning training and development programs are designed to expand your technical expertise and leadership skills, helping you build the career you’ve always envisioned. Here, you’ll find a welcoming workplace built on respect, collaboration and community—where you have the freedom to grow in a world of opportunity.

As an Equal Opportunity Employer, we believe in your potential and are here to help you achieve it. All your information will be kept confidential according to EEO guidelines.

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