Case Study: Using Source to model Sydney's future water security

Two University of Sydney engineering students are helping tackle one of Sydney’s biggest future challenges: water security.

Using Australia’s leading water modelling platform, eWater Source, Irene Emvalomas and Karima Touma explored how climate change, population growth and changing hydrological conditions could impact Sydney’s drinking water supply. Their research reveals how advanced modelling tools are shaping smarter, more resilient approaches to urban water management, and why the next generation of engineers will play a critical role in securing Australia’s water future.

Two graduating civil engineering students at the University of Sydney, Irene Emvalomas and Karima Touma, have undertaken complementary honours thesis projects examining the future security of Sydney’s urban water supplies.

Together, their research highlights one of the most important challenges facing Australia’s largest city: how to ensure reliable water supplies in a future shaped by climate uncertainty, population growth and increasing pressure on existing infrastructure.

Irene Emvalomas focused on modelling the impacts of population growth and climate change on the Warragamba Dam system, which provides the majority of Greater Sydney’s drinking water. Her thesis explored how increasing water demand, combined with changing hydrological conditions, could affect long-term water security across the Greater Sydney region.

Warrragamba Dam and Catchment, NSW, Australia (Credit: Getty Images)

Using eWater Source, Irene developed a scenario-based modelling framework that simulated future supply-demand interactions under different combinations of climate and population growth assumptions. Her work demonstrated that increasing population demand significantly accelerates storage declines during drought conditions, while climate-adjusted inflow reductions further intensify the risks of supply shortfalls.

Karima Touma’s thesis approached the issue from a broader urban water security perspective, seeking to redefine how Sydney’s water resilience should be understood in a changing climate.

Her work examined the strengths and limitations of existing modelling frameworks while developing a new eWater Source model calibrated against historical flow data from 1990–2023. She then applied moderate and severe future climate scenarios to evaluate how Sydney’s hydrology may change over coming decades.

Warrragamba Dam, NSW Australia (Credit: Getty)

eWater Source is Australia’s leading integrated water modelling platform and is widely used by water utilities, governments, researchers and catchment management agencies. The software allows researchers to combine rainfall, streamflow, evaporation, catchment behaviour, water demand, infrastructure operations and climate scenarios within a single integrated modelling environment.

In these projects, Source enabled the students to move well beyond static calculations or simplified spreadsheet analyses. Instead, they were able to simulate how complex water systems behave dynamically over long periods under changing environmental and societal conditions.

Tools like eWater Source allow planners and researchers to evaluate “what-if” scenarios before crises occur. They support adaptive planning, identify vulnerabilities, test infrastructure resilience, and help governments make more informed long-term investment decisions.

These projects also demonstrate the growing importance of modelling literacy within civil and environmental engineering education. By learning to use sophisticated platforms such as eWater Source, students gain practical skills directly relevant to the future of water resource management in Australia. Their work contributes not only to academic understanding, but also to the broader national conversation about climate resilience, urban infrastructure, and sustainable water futures.

Together, these two theses illustrate how advanced modelling tools can transform our understanding of urban water security, and how the next generation of engineers is already contributing valuable insights into the future management of Sydney’s most critical resource.