Principal Wastewater Modeller

Job Location

UK – Edinburgh – Tanfield

• Serves as the principal technical advisor and subject matter expert for wastewater system modeling and analysis, providing guidance to project teams and junior staff.
• Provides specialised technical input to planning studies, alternatives analyses, and design related to wastewater collection, conveyance, treatment, and wet weather system performance.
• Develops, maintains, and standardises wastewater modelling methodologies, procedures, and best practices to ensure high‑quality, defensible and cost‑effective technical work.
• Leads and participates in interdisciplinary reviews of planning, modelling and design deliverables to ensure consistency between hydraulic modelling, process design and overall project objectives.
• Develops and reviews planning‑level and design‑level cost estimates, including capital improvement costs and level‑of‑effort estimates for modelling and technical analyses.
• Applies expert knowledge across all phases of wastewater modelling contributions to PS&E packages, including flow development, model calibration, capacity analysis and support of design criteria.
• Performs quality control and peer review of hydraulic and process model set‑ups, assumptions, calculations and technical documentation.
• Prepares and reviews technical memoranda, modelling reports and specification sections related to wastewater modelling, data requirements and performance criteria.
• Provides technical input to the development of engineering budgets, schedules and work plans, ensuring modelling tasks are appropriately scoped and aligned with regulatory and project requirements.
• Collaborates with the dynamic Water business, working alongside approximately 700 experts across the UK & Ireland and the Edinburgh team, contributing to projects from concept to completion.

You’ll thrive in an inclusive and forward‑thinking environment where your contributions are valued. You’ll enjoy a range of core and personalised benefits designed to support your future and well‑being, customised to fit your lifestyle. Take advantage of career development opportunities, technical practice networks, AECOM University, volunteering days and our flexible hybrid working model to ensure a work‑life balance that suits you.

We recognise that everyone’s circumstances are different, so we’re more than happy to discuss part‑time or flexible working arrangements.

Here’s what we’re looking for:

• A degree (or equivalent) in Civil Engineering, Environmental Sciences, GIS, Geography, or a similar subject.
• Chartered member or approaching chartership with ICE or CIWEM.

Extensive experience in wastewater modelling.

Strong proficiency in GIS and data analysis to support wastewater modelling, particularly using ArcGIS for network development, spatial data management and results visualisation.

Understanding of wastewater hydrology and hydraulics, including dry weather flow, wet weather flow, infiltration and inflow (I/I) and climate change impacts, within the UK and international regulatory contexts.

Proven experience with wastewater and integrated urban drainage modelling platforms such as Innovyze Info Works ICM (wastewater modules), Info Works WS Pro, SWMM or equivalent tools used for sewer system and integrated catchment modelling.

Demonstrated experience acting as a technical lead for wastewater modelling projects, responsible for model strategy, quality assurance, client interface and mentoring junior modelers.

Strong background in water and wastewater consultancy, delivering planning, regulatory and capital improvement projects for utilities and public‑sector clients.

We celebrate diversity, including neurodiversity, and believe it enriches our team. We welcome applications from all backgrounds and abilities. If you are an applicant with a disability that requires reasonable accommodation to complete the application process, please contact us at Reaso

We are a Disability Confident Employer and will offer an interview to applicants who have a disability or long‑term condition who meet the minimum/essential criteria for the role. Please let us know using this email address Reaso if you would like to apply through the Disability Confident Interview Scheme.

All your information will be kept confidential according to EEO guidelines.