Principal Mechanical Engineer

Join to apply for the Principal Mechanical Engineer role at Mott MacDonald.

Mott MacDonald Bentley is a joint venture business focused on delivering water and wastewater projects across the UK. As a Principal Mechanical Engineer you will contribute to projects that significantly impact our environment and communities, focusing on the feasibility, design, construction, and commissioning of water and wastewater infrastructure.

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• Lead and oversee the design, planning, and execution of the mechanical engineering aspects of our projects.
  
• Provide technical expertise and guidance to our mechanical engineers and project teams, developing knowledge and excellence within the team.
  
• Mentor and develop junior engineers and team members.
  
• Lead the mechanical design of water and wastewater infrastructure projects, including P&IDs, valve schedules, pumps, tanks, process equipment, above‑ground pipework, and lifting and access steelwork.
  
• Coordinate with Electrical, Civil, Geotechnical, and Process engineering teams.
  
• Work closely with project teams to apply client asset standards and engage in technical discussions on best practice and standards waivers.
  
• Collaborate with commercial, operational, and construction teams to develop efficient, practical, and safe solutions throughout design and construction stages.
  
• Positively engage with the client, managing relationships and adopting a one‑team approach to support them in achieving their aims.
  

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• Chartered Mechanical Engineer or above.
  
• Degree in Mechanical Engineering or related field.
  
• Strong knowledge of the water and/or wastewater industry.
  
• Strong knowledge of mechanical engineering principles, practices, and standards in process industries.
  
• Excellent communication, leadership, and problem‑solving skills.
  
• Proven ability to manage multiple design tasks and meet deadlines.
  

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• MMB match employee pension contributions between 4.5% and 7%.
  
• Annual bonus schemes and payment of professional institution subscription costs.
  
• Minimum 33 days holiday per year, with options to buy, sell, or carry over through our flexible benefits programme.
  
• Life Assurance, Private Medical Insurance, Critical Illness Insurance and health screening options.
  
• Flexible working arrangements and support for responsibilities beyond the workplace.
  
• Advanced Employee Networks supporting LGBTQ+, gender, race and ethnicity, disability, and parents/carers communities.
  
• Enhanced family leave policies, including 26 weeks paid maternity and adoption leave, two weeks paid paternity/partner leave, and shared parental leave options.
  
• Up to two paid additional days leave for those with significant caring responsibilities.
  
• Structured development schemes, fast‑tracked chartership reviews, mentoring, and tailored training opportunities.
  

This role is employed by Mott MacDonald but will involve working across the joint venture business, with both Mott MacDonald and JN Bentley colleagues.

Location: Bristol, GB

Contract Type: Permanent

Work Pattern: Full Time

Job Ref: 12724

We welcome applications from all sectors of the community and are committed to building a diverse workplace where everyone feels included and treated with respect.

To apply, contact .

We do not offer sponsorship for the Skilled Worker visa, but welcome candidates with alternative immigration routes.