Lead Process Engineer - Associate Director - Water Sector

Ayesa; Greater London; Hybrid; GBP 100,000 - 125,000; Full time

Job summary

A global engineering consultancy in Greater London is seeking a Lead Process Engineer – Associate Director to join its Water Infrastructure Team. This role involves leading design and delivery of process engineering solutions for water and wastewater projects. The candidate should possess over 10 years of experience in this field, be Chartered, and have a strong understanding of relevant UK regulations and standards. The position offers a competitive salary, hybrid working, and opportunities for professional development.

Benefits

Competitive salary and benefits package

Hybrid and flexible working (2-3 days from home)

Professional development and chartership support

Generous annual leave with additional days based on service

Qualifications

• 10+ years’ experience in water, wastewater, or industrial effluent treatment design.
• Proven ability to develop complete process solutions from concept to detailed design.
• Experience leading HAZOP / HAZID workshops and supporting commissioning activities.

Responsibilities

• Lead process design for treatment plants and systems.
• Ensure compliance with UK regulations and client requirements.
• Provide technical leadership and mentorship to engineers and graduates.

Skills

Water and wastewater treatment process principles

Leadership and client engagement skills

Developing PFDs and P&IDs

Understanding of UK industry standards

Education

Degree in Chemical, Process, or Environmental Engineering

Chartered Engineer (CEng) status or equivalent

Tools

BIM

Job description

Company Description

Company Overview

Ayesa is a global, forward‑thinking engineering and technology consultancy with 13,000 employees in 23 countries. We are committed to diversity, inclusion, equity, and sustainability – values that drive our innovation and growth across infrastructure, water, transport, energy, and environmental sectors.

Position

The Opportunity

We’re looking for a Lead Process Engineer – Associate Director to join our Water Infrastructure Team within the UK, taking a key technical and leadership role in the design, coordination, and delivery of process engineering solutions across water, wastewater, sludge treatment centres, biological and utilities projects. You’ll help shape strategies, mentor engineers, and drive excellence from concept through to commissioning.

What You’ll Be Doing

• Lead process design for treatment plants, pumping stations, and utility systems.
• Define process schemes, develop mass balance and hydraulic profiles and calculations, and specify treatment equipment.
• Ensure compliance with UK regulations and client requirements (DWI, EA, Ofwat, BSI, WIS, IGN, SuDs, etc.).
• Lead technical reviews, challenge assumptions, and ensure design integrity and performance.
• Coordinate across civil, mechanical, electrical, and control disciplines in a multidisciplinary environment.
• Develop and manage PFDs, P&IDs, design reports, and technical specifications.
• Support BIM and digital design integration within process design workflows.
• Present and facilitate HAZOP, HAZID, and SIL studies.
• Lead or support design and build (D&B) projects in collaboration with utilities and delivery partners.
• Oversee scope, schedule, and budget control to ensure efficient delivery.
• Provide technical leadership and mentorship to engineers and graduates.
• Engage directly with clients to shape solutions and lead proposals or bids.
• Promote innovation, sustainability, and digital best practices within the team.

Key Accountabilities

• Deliver robust, efficient, and compliant process design solutions.
• Collaborate effectively within multidisciplinary teams.
• Manage workload, priorities, and project performance.
• Ensure adherence to Ayesa’s Integrated Management System (IMS).
• Represent Ayesa professionally, building strong client relationships.

Requirements

What You Bring

Experience & Qualifications

• 10+ years’ experience in water, wastewater, or industrial effluent treatment design.
• Chartered Engineer (CEng) status or equivalent.
• Degree in Chemical, Process, or Environmental Engineering (Master’s desirable).

Skills & Knowledge

• Deep understanding of water and wastewater treatment process principles.
• Proven ability to develop complete process solutions from concept to detailed design.
• Experience with UK and Ireland industry standards and specifications.
• Skilled in developing PFDs, P&IDs, and conducting process calculations.
• Experience leading HAZOP / HAZID workshops and supporting commissioning activities.
• Strong leadership, coordination, and client engagement skills.
• Familiarity with BIM, digital design, and sustainable engineering practices.

Other information

What’s In It for You

• Competitive salary and benefits package.
• Hybrid and flexible working (2-3 days from home).
• Pension matching, income protection, and life assurance.
• Professional development and chartership support.
• Sustainability and innovation‑focused culture.
• Socials, recognition awards, and wellbeing initiatives.
• Generous annual leave with additional days based on service.

We’re Inclusive by Design

Ayesa is proud to be an equal opportunity employer. We value and celebrate diversity in all its forms, including but not limited to age, disability, gender identity, race, religion or belief, sex, sexual orientation, and socio‑economic background or neurodiversity. We believe that a diverse workforce fosters innovation and stronger outcomes. We are committed to inclusive hiring practices, providing reasonable adjustments for applicants and employees with disabilities, and ensuring equal access to opportunities for learning, development, and progression across our organisation.