Senior Wastewater Network Modeller

Southern Water; United Kingdom; Hybrid; GBP 36,000 - 60,000; Full time

Job summary

Southern Water is seeking a Senior Wastewater Network Modeller to lead high-quality modelling across risk assessments, growth planning, resilience studies, and optioneering. You will mentor junior modellers and graduates, promoting a collaborative and technically strong team.

You will oversee wastewater modelling using InfoWorks ICM, ensuring models are robust, auditable, and aligned with best practice. You will drive automation and continuous improvement to support resilient networks and

Qualifications

• 5 to 10 years wastewater modelling experience.
• Experience delivering UK-based wastewater projects.
• Chartered or near-chartered status.
• Programming experience (Python or Ruby) is desirable.

Responsibilities

• Lead and deliver wastewater modelling across risk assessments, growth planning, resilience studies and optioneering.
• Mentor junior modellers and graduates, promoting collaboration and technical excellence.
• Quality-check outputs and translate results into actionable engineering recommendations.
• Lead stakeholder engagement with internal teams, clients and regulators.
• Drive process improvement and automation to strengthen digital capability.

Skills

Wastewater modelling

UK based projects

Chartered status

Python

Ruby

Tools

InfoWorks ICM

Job description

Closing Date

2026-08-28

Job Title:

Senior Wastewater Network Modeller

Location:

Hybrid working

Contract Type:

Permanent

Hours:

37

Salary:

Up to £60,000 based on skills & experience

About the role:

As a Senior Wastewater Network Modeller, you will lead the delivery of high-quality wastewater network modelling across risk assessments, growth planning, resilience studies, and optioneering. You will mentor and develop junior modellers and graduates, promoting a collaborative and technically strong team.

You will oversee and carry out wastewater modelling using InfoWorks ICM, ensuring models are robust, auditable, and aligned with best practice. The role includes improving workflows through automation, strengthening digital capability, and driving continuous process improvement.

You will review and challenge technical outputs, provide clear technical direction, and turn complex modelling insights into practical, sustainable engineering solutions. Your work will support long-term environmental stewardship and the development of resilient wastewater networks that meet regulatory and future growth needs.

What you will be responsible for:

• Support, mentor, and train junior staff and graduates across modelling, analysis, and design tasks.
• Lead and contribute to risk assessments, growth modelling, resilience studies, and technical design projects.
• Quality-check modelling and design outputs to ensure technical excellence.
• Produce robust outline and detailed wastewater network solutions aligned with best practice and regulatory requirements.
• Interpret modelling results and translate complex data into clear, actionable engineering recommendations.
• Lead stakeholder engagement, presenting technical findings to internal teams, clients, and regulators.
• Contribute to project planning, scoping, and programme management to ensure timely, high-quality delivery.

What you'll bring to the role:

Essential

• Strong technical capability to lead small-scale projects
• 5 to 10 years wastewater modelling experience
• Experience delivering UK-based wastewater projects
• Chartered or close to chartered status

Desirable

• Programming experience (Python or Ruby)
• Experience with digital design and automation tools

About Southern Water

Southern Water is at the forefront of transforming Britain’s water industry, investing significantly to enhance resilience, sustainability, and service excellence. With £7.8bn planned investment for 2025-30, this is an unparalleled opportunity to join a business committed to delivering a generational shift in the way water services are managed.

You will be joining at a time of significant change, working alongside a highly skilled leadership team with a clear vision for the future. We offer an environment where senior professionals can make a meaningful impact, influence major strategic decisions, and drive long-term value creation

Our commitment to inclusion

At Southern Water, we believe diverse perspectives drive innovation. If you’re passionate about making a positive impact and think you can bring value to our team, we’d love to hear from you—even if you don’t tick every box. Your unique skills and experiences could be exactly what we need.

Our Commitment to Diversity

We welcome applicants from all backgrounds, identities, and experiences. We do not discriminate based on race, ethnicity, gender, sexual orientation, age, disability, religion, or any other protected characteristic. If you need reasonable adjustments during the recruitment process, please let us know.

Additional information:

In line with Southern Water’s security requirements, successful candidates will be required to provide evidence of their identity, eligibility to work in the UK, criminal record check (DBS) and verification of their employment and/or education history for the past three years.

Appointment to this role is subject to the successful completion of all pre-employment checks, including security vetting.

Please note that if a candidate does not meet the required security standards or fails to pass the vetting process, Southern Water reserves the right to withdraw the offer of employment. Some positions may also require higher levels of security vetting, which may involve providing additional documentation.