Location
Glasgow or Edinburgh, with hybrid working supported. Regular office, client and site visits expected.

Hours
Flexible working arrangements can be considered to balance focused technical work with team and client interaction.

Salary
Negotiable

About the Role
Tetra Tech’s Water Consultancy is seeking a Principal Wastewater Modeller to build and lead a high-performing team of Wastewater Hydraulic Modellers. You will lead technical delivery across major UK frameworks, including Scottish Water, from feasibility through to detailed design. The role involves defining catchment strategies, directing hydraulic modelling and design inputs, and ensuring robust HSE, quality and governance standards across multi-million-pound wastewater programmes. Day to day, you will manage modelling standards, commercial performance, resource planning and risk, while supporting bids, proposals and client engagement with water companies and delivery partners.

Your impact in this position includes strengthening modelling assurance, guiding complex catchment interventions, developing and mentoring a capable modelling team, improving workflows, and influencing investment decisions that reduce pollution and flood risk. Longer term, you will have the opportunity to apply digital tools to improve delivery and lead low-carbon, resilient solutions on significant wastewater programmes.

Tetra Tech is a leading consulting and engineering services provider working across the full project lifecycle worldwide. We offer a collaborative environment that supports individual performance, innovation, and creativity, delivering sustainable and resilient solutions for public and private sector clients. We are committed to equality and will make reasonable adjustments to support candidates and employees requiring additional arrangements.

Experience
- Proven expertise in InfoWorks ICM, model development, calibration and delivery of robust catchment strategies across wastewater networks and frameworks.
- Ability to produce auditable, compliant modelling outputs while maintaining strong quality, HSE and governance controls.
- Experience managing forecasts, commercial risk, resources and contributing to bid and proposal development.
- Track record of leading, mentoring and growing multidisciplinary teams.
- Ability to communicate complex findings clearly to clients and stakeholders.
- Proficiency in digital innovation and data tools such as GIS, Python, FME, Power BI or similar to automate workflows and support evidence-based decisions.

About you
Motivated leader with strong technical expertise and excellent communication skills. Able to manage multiple priorities and foster a collaborative team environment. Committed to delivering high-quality, sustainable wastewater solutions and continuous improvement.

Qualifications
- Degree in a relevant technical discipline is essential.
- Postgraduate qualification is desirable.
- Chartered status or working towards chartership is preferred.
- Professional affiliation with CIWEM, ICE or IWater is preferred.