Name

Challenges and opportunities for 21st century storm and wastewater infrastructure

Speakers

Fergus Clifford

Authors

Sean Mulligan, Fergus Clifford and Mark Willson, Vortech Water Solutions, Ireland
Eoghan Clifford, University of Galway, Ireland

Description

Combined sewer systems remain a foundational element of urban wastewater infrastructure worldwide. Originally designed to manage stormwater surges by discharging excess flows via combined sewer overflows (CSOs), these systems are now under unprecedented strain. Rapid urbanization, population growth, and climate change have dramatically increased the frequency and volume of CSO events—far beyond their intended capacity. This presentation explores the evolving global challenges facing wastewater conveyance infrastructure, with a focus on combined sewer networks. It highlights the growing regulatory scrutiny and societal expectations around water quality, environmental protection, and climate resilience. As utilities invest in CSO mitigation through storage, interception, and treatment, attention must also turn to the aging conveyance and treatment assets that underpin these systems—many of which are ill-equipped to handle future demands without significant upgrades. The session will examine innovative infrastructure strategies that balance economic feasibility with environmental performance. It also aims to discuss the often-overlooked issue of greenhouse gas emissions from conveyance and treatment processes, and how these can be mitigated through holistic design and operational optimization. By synthesizing global case studies and regulatory frameworks, this presentation aims to guide decision-makers toward infrastructure solutions that maximize social value while meeting complex compliance requirements.

Time

9:12 AM - 9:25 AM

Location Name

Room 2

Track

09:00 - 10:40 CSOs & Stormwater