Lead Mechanical Design Engineer – Water & Wastewater Systems

AF ECO Ltd; Havant; On-site; GBP 55,000 - 85,000; Full time

Benefits offered by this job

Medicash plan

Life insurance

Benefits portal

Company pension

25 days holiday

Job summary

AFECO is seeking a Senior Mechanical Design Engineer to lead the mechanical design of water and wastewater assets across the project lifecycle, from concept through commissioning. You will mentor junior engineers and collaborate with multi‑disciplinary teams to deliver robust solutions.

The role requires strong technical capability, familiarity with standards, and experience delivering designs from concept to construction across the water sector.

Qualifications

• Essential Degree (or equivalent) in Mechanical Engineering.
• Significant experience in the water or wastewater sector.
• Strong knowledge of mechanical equipment used in water treatment and conveyance.
• Experience delivering designs through concept, detailed design, and construction stages.
• Familiarity with relevant standards (e.g. ISO, BS, EN, WIMES, client standards).
• Desirable Experience working on regulated water frameworks.
• Site experience including commissioning or construction support.
• Knowledge of asset management and whole‑life cost analysis.
• Experience with NEC or other engineering contracts.
• Technical Skills Mechanical design and specification.
• Pumping system design and hydraulics (desirable).
• Design risk assessment and CDM compliance.
• 2D/3D CAD tools (e.g. AutoCAD, SolidWorks).
• Engineering calculations and reports.

Responsibilities

• Lead mechanical design activities for water and wastewater treatment projects, including pumping stations, treatment works, pipelines, and associated infrastructure.
• Produce and review mechanical designs, calculations, specifications, schedules, and drawings.
• Ensure designs comply with relevant standards, legislation, client specifications, and health & safety requirements.
• Undertake optioneering and value engineering to balance cost, performance, risk, and operability.
• Support constructability, commissioning, and handover activities.
• Specify, size, and select mechanical equipment such as pumps, valves, screens, blowers, mixers, and mechanical treatment processes.
• Review supplier technical submissions and manage technical interfaces with vendors.
• Assess whole‑life cost, reliability, and maintainability of mechanical systems.
• Work closely with process, civil, electrical, and ICA engineers to deliver integrated solutions.
• Liaise with clients, contractors, suppliers, and operations teams.
• Provide technical input during design reviews, HAZID/HAZOP, and risk workshops.
• Mentor and technically support graduate and intermediate engineers.
• Review and approve work produced by others.
• Contribute to the development of internal standards, best practices, and lessons learned.

Skills

Mechanical design

Pumping hydraulics

CAD tools

Engineering calculations

CDM compliance

Education

Bachelor's degree in Mechanical Engineering

Tools

AutoCAD

SolidWorks

Job description

AFECO is seeking a Senior Mechanical Design Engineer to lead the mechanical design of water and wastewater assets across the project lifecycle, from concept through commissioning. You will mentor junior engineers and collaborate with multi‑disciplinary teams to deliver robust solutions.

The role requires strong technical capability, familiarity with standards, and experience delivering designs from concept to construction across the water sector.