Hydraulic Modeller – Water & Wastewater in Cardiff

Arup's purpose, shared values and collaborative approach has set us apart for 80 years, guiding how we shape a better world. We work across the entire water cycle, with utilities, local and regional governments, commercial and domestic water users and other partners. From designing and maintaining key water infrastructure to advising on natural catchments and flood defences, we help clients to consider the long-term economic, environmental and social dimensions of their proposals.

The Opportunity

We are looking for a wastewater hydraulic modeller to support and enhance our team. You will be joining a dynamic multi-disciplinary technical delivery team working on a wide variety of projects with local clients across Wales and Southwest England. These include catchment scale wastewater modelling and design projects, delivering WINEP/NEP and storm overflows investment to improve rivers and coastal waters across the region. You will be part of a team that will develop and deliver innovative solutions to solve complex problems for our clients and their customers.

You will deliver a wide variety of projects, and see your solutions developed from start to finish. We live our Strategy every day 'sustainability is everything' and we actively promote, prioritise and deliver nature-based solutions. We are passionate about our people; every person is guided and mentored in their career path and encouraged to work towards being the best that they can be. Every year we invest in our people to allow them to pursue new ideas, and to develop a forward-thinking team at the forefront of innovation.

At Arup, we invest in our own bespoke research every year, often working in partnerships, developing our knowledge, author industry guidance, and build digital tools and products. You will be encouraged to get involved in this research as part of our global modelling centre of excellence in the West working alongside civil engineers, digital specialists and expert modellers in a truly blended team environment.

Is this role right for you? You will have the opportunity to deliver wastewater network modelling projects across the entire design process. You will use 1D hydraulic models for risk analysis and the development of solutions to improve water quality and reduce flood risk, with particular focus on storm overflows and wastewater treatment works across Wales and Southwest England. As part of this, you will also develop wastewater catchment survey specifications and investigations, liaise with and manage survey sub-contractor, and spend time on site during the project lifecycle.

You will be part of our Modelling Centre of Excellence and embedded in our global training programme. You will also be part of our local multi-disciplinary expert water team, delivering holistic catchment solutions with a strong focus on nature-based solutions. This will include developing technical reports, hydraulic model build and analysis, business case development, multi-capitals economics, supporting calculations, and other key modelling deliverables. You will also be encouraged and supported to develop and apply digital tools to enhance, optimise, and automate our offering. You will receive training and support across all of the above and more.

In addition, you will work closely with clients and present modelling and project outputs to their Operations, Asset Management, Environmental, and Modelling teams.

We are looking for qualifications, skills and knowledge in the following:

• Practical experience in hydraulic modelling techniques within the UK water industry, specifically using InfoWorks ICM, ideally including Level 1 UPM water quality modelling
• Degree (or equivalent) in Engineering, Geography, Environmental Science, or a related discipline, with progress toward chartership with an appropriate professional body
• Proven track record of successfully delivering water projects in the UK, including collaboration with both public and private sector clients and regulatory bodies

What we offer you

At Arup, we care about each member's success, so we can grow together. Guided by our values, we provide an attractive total reward package that recognises the contribution of each of our members to our shared success. As well as competitive, fair and equitable pay, we offer a career in which all our members can belong, grow and thrive through benefits that support health and wellbeing, a wide range of learning opportunities and many possibilities to have an impact through the work they do.

We are owned in trust on behalf of our members, giving us the freedom, with personal responsibility, to set our own direction and choose work that aligns with our purpose and adds to Arup’s legacy. Our members collaborate on ambitious projects to deliver remarkable outcomes for our clients and communities. Profit Share is a key part of our reward, enabling members to share in the results of our collective efforts. We also provide Private medical insurance, Life assurance, Accident insurance and Income protection cover. In addition, you'll have access to flexible benefits to help you look after all aspects of your wellbeing and give you the freedom and flexibility to find the best solutions for you, your family, and your individual needs.

Different people, shared values

Arup is an equal opportunity employer that actively promotes and nurtures a diverse and inclusive workforce. We welcome applications from individuals of all backgrounds, regardless of age (within legal limits), gender identity or expression, marital status, disability, neurotype or mental health, race or ethnicity, faith or belief, sexual orientation, socioeconomic background, and whether you're pregnant or on family leave. We are an open environment that embraces diverse experiences, perspectives, and ideas – this drives our excellence. Guided by our values and alignment with the UN Sustainable Development Goals, we create and contribute to equitable spaces and systems, while cultivating a sense of belonging for all.

Our internal employee networks support our inclusive culture: from race, ethnicity and cross-cultural working to gender equity and LGBTQ+ and disability inclusion – we aim to create a space for you to express yourself and make a positive difference.

We are committed to making our recruitment process and workplaces accessible to all candidates. Please contact maria.mindrut@arup.com to let us know if you need any assistance or reasonable adjustments throughout your application or interview process, and/or to perform the essential functions of the role. We will do everything we can to support you.

Our Application Process

All applications will be considered, and we will make every effort to respond within 72 hours of receipt. Please note that response times may be subject to delays during the festive period. Stay safe online – Arup will never ask for your bank details as part of our recruitment process.

Closing Date 05.08.2026. We may close the role earlier than the advertised date should we receive a large number of applications, so please ensure you apply early.