Associate Technical Director - Surge / CFD Modelling

Arcadis is the world's leading company delivering sustainable design, engineering, and consultancy solutions for natural and built assets. We are more than 34,000 people, in over 30 countries, dedicated to improving quality of life. Everyone has an important role to play. With the power of many curious minds, together we can solve the world’s most complex challenges and deliver more impact together. Role description: This is a career-defining opportunity for a recognised technical expert in hydraulic engineering to lead Arcadis's specialist capability in pressure surge (transient hydraulics), Computational Fluid Dynamics (CFD), and advanced hydraulic modelling across water and wastewater infrastructure in the UK and internationally. As Associate Technical Director, you will be the technical conscience of the Water business for this discipline, setting standards, leading complex studies, building and mentoring a team of specialist engineers, and positioning Arcadis as the go-to firm for clients who need rigorous, innovative hydraulic engineering on their most critical assets. Working within a major AMP8 framework delivery environment, and operating within a three-tier delivery structure alongside major contractors and direct clients, you will translate advanced hydraulic modelling into practical, defensible engineering solutions that reduce infrastructure risk, improve asset reliability, and inform investment decisions at programme scale. Role accountabilities:

Technical Leadership & Delivery

▪ Technical Authority. Act as Arcadis's named technical authority and final reviewer for pressure surge, transient hydraulics, and CFD studies across capital schemes, framework programmes, and operational risk work. ▪ Complex Modelling. Direct and technically oversee advanced transient and CFD studies, including undulating rising mains, pump-station protection, air entrainment, multiphase flow, priming/draining systems, and treatment plant internal hydraulics, ensuring outputs are defensible and client-ready. ▪ Standards & Governance. Develop, maintain, and embed Arcadis's technical standards, model assurance frameworks, design guidance, and QA protocols for surge and CFD, ensuring consistency across projects and programmes. ▪ Tool Expertise. Apply and champion industry-leading modelling platforms including HAMMER, Wanda, VariSim, ANSYS Fluent, OpenFOAM, and related hydraulic analysis tools such as HADES; evaluate and introduce new tools where these advance our capability. ▪ Innovation & Digital. Drive the integration of data-driven methods, AI/ML applications, digital twin approaches, and automated workflows into hydraulic modelling practice, positioning Arcadis ahead of sector development in this discipline. ▪ Multidisciplinary Integration. Provide cross-functional technical leadership to water quality, process, civil, and design teams to improve whole-system outcomes and reduce risk across complex, multi-disciplinary programmes.

Commercial Development & Client Ownership

▪ Client Relationships. Build and maintain trusted technical relationships with major UK water utilities (e.g. Thames Water, Anglian Water, Severn Trent, Southern Water, United Utilities) and contractors, acting as a recognised technical partner rather than a transactional supplier. ▪ Business Development. Identify, pursue, and win new work, support bid preparation, write technical sections of proposals, attend client presentations, and develop the pipeline for surge, CFD, and hydraulics services within Arcadis's Water Management business. ▪ Framework Delivery. Lead technical delivery within AMP8 framework programmes, managing Arcadis's obligations and quality standards within complex multi-party delivery structures. ▪ Commercial Accountability. Manage project finances, including fee negotiation, earned value tracking, cost control, and variation management, to deliver studies profitably and to schedule. ▪