Description

As a Principal Process Engineer within the Water Infrastructure Team, you will play a senior technical and leadership role, primarily responsible for the design, coordination, and delivery of process engineering solutions within water, wastewater, sewage treatment and utilities sectors, with the potential to expand into energy, transport, and environmental infrastructure sectors.

• Develop and manage process flow diagrams (PFDs), P&IDs, design reports, and technical specifications.
• Engage directly with clients at a senior level — helping shape project briefs, proposals, and process solutions.
• Represent and promote Ayesa in a professional manner and develop effective working relationships with clients and potential clients
• Define treatment process schemes, undertake mass balance and hydraulic calculations, and specify equipment (e.g. aeration systems, chemical dosing, sludge handling).
• Oversee multidisciplinary coordination — integrating process design with civil, mechanical, electrical, and control system disciplines.
• Management of projects in compliance with Ayesa's Integrated Management System (IMS)
• Interface with other engineering disciplines including civil, M&E and structural
• Lead or support design and build (D&B) projects, working closely with contractors, utilities and delivery partners.
• Carry out design reviews, challenge assumptions, and sign off key deliverables to ensure technical robustness.
• Manage project scope, schedules, and budgets while maintaining high technical standards.
• Guide and mentor junior process engineers and graduates.
• Has undertaken preliminary and detailed design of water / wastewater treatment plants based on data provided and achieved the desired treatment criteria
• Oversee process commissioning, testing, and performance verification on site when projects move into delivery phases.
• Contribute to business development, proposal writing, and framework management with key UK utilities.
• Integrate within our multi-disciplinary design team to deliver robust design solutions to clients
• Adheres to all Codes of Practice, Design Standards and Health & Safety Regulations
• Ensure designs meet UK regulations, standards, and client specifications, such as DWI, EA, or Ofwat requirements.
• Lead the process design for treatment plants, pumping stations, pipelines, and utility systems.
• Lead internal design reviews and promote best practices in process design, sustainability, and digital delivery.
• Ensure all work aligns with BIM and digital design workflows where applicable.

Requirements

• Has achieved Chartered status
• A degree and ideally a master’s in chemical/process / environmental Engineering
• Deep understanding of the principles of water treatment and/or wastewater & industrial effluent treatment
• Demonstrate an ability to develop process mass balance, hydraulic, energy, mechanical calculations as part of the detailed design
• Ability to communicate effectively with clients and senior staff
• Proven track record in process selection, process design, application engineering, proposal support and operational support
• A team player with a mature approach including first-class inter-personal skills
• Present designs and/or scribe HAZOP, HAZID, and SIL studies.
• Proven track record in the development of process solutions in industrial and municipal settings, and in accordance with specifications used in Ireland and United Kingdom
• Demonstrate an ability to develop drawings of equipment and plant layouts as required Developing PFDs (Process Flow Diagrams) and P&IDs (Process & Instrumentation Drawings)
• Minimum of 10 years’ experience in water treatment and/or wastewater & industrial effluent treatment.
• Ability to manage a challenging workload.
• Proven track record in the development of the whole cycle of the treatment process from the concept to the detailed design stage

Benefits

📚 Professional Development and Chartership Support.

🏡 Hybrid Work Model (2–3 days from home).

🎉 Socials, Recognition Awards & Wellbeing Initiatives.

🕓 Flexible Hours 37.5 per week (Core: 10am–4pm Mon–Thu, 10am–3pm Fri).

✅ Competitive Salary commensurate with skills and experience.

🛡️ Income Protection & Life Assurance.

💰 Pension Matching & Financial Planning Support.

🤝 Employee Assistance Programme (EAP).

🌴 Generous Annual Leave with Additional Days Based on Service.

Training + Development

Interview process

Visa Sponsorship

Security clearance