In profile: Wenhui Wu, PhD student

Under the effects of urbanisation and climate change, Australia and many other cities are expecting existing drainage systems to fast become overwhelmed and pluvial flooding to increase in both frequency and severity. While Water Sensitive Urban Design (WSUD) is touted as the answer to many urban water challenges, placing nature and liveability at the forefront of modern engineering solutions, it appears that a WSUD approach to pluvial flooding has not yet been prioritised.

Through her PhD research at UNSW, Wenhui Wu is aiming to change that. She is developing  an integrated WSUD planning model specifically for pluvial flood mitigation, saying that her model will “help urban planners and flood risk managers to identify and plan robust WSUD options that perform well under different scenarios to achieve flood resilience.”

Wenhui says that despite the ability of WSUD to improve water quality, enable stormwater harvesting and reduce runoff, the application of WSUD for flood mitigation has been limited in Australia.

“Current WSUD planning practice often only explores a handful of WSUD options and scenarios which are not sufficient for addressing the high uncertainties in future conditions. There is a lack of a planning model capable of strategically planning WSUD for flood mitigation in a fast and exploratory manner.”

Using fast flood simulation and machine learning techniques, Wenhui’s model will consider the use of different WSUD technologies such as raingardens, rainwater tanks and surface wetlands to manage stormwater and mitigate flooding.

“A robust WSUD flood mitigation solution would be one that can perform in the long term, amid uncertainties of climate change and urban development,” says Wenhui.

“The proposed solutions from my model are the results of exploratory modelling, which looks at thousands of possible WSUD combinations and identifies the top-ranking solutions that perform well under different scenarios. We believe these solutions are more robust because they are more likely to be able to cope with future uncertainties than those generated using only a handful of projected scenarios.”

It’s no surprise that Wenhui’s career has taken this path after growing up in a flood-prone city in South China. She went on to complete a Bachelor of Environmental Science at the University of Sheffield in the United Kingdom, and then a Master of Science in Water Science, Policy and Management at the University of Oxford.

A robust WSUD flood mitigation solution would be one that can perform in the long term, amid uncertainties of climate change and urban development

Wenhui Wu, PhD student

“My Master’s degree stimulated my interest in flood risk management and provided me exposure to the potential use of nature-based stormwater management solutions for flood mitigation,” says Wenhui.

“When working as a Sustainable Urbanisation Policy Officer, I had the opportunity to assess and report on the development and use of these solutions in UK and China. Through this, I built a much better understanding of the multi-benefits of these solutions and became interested in how we can plan them to build more sustainable and resilient cities.”

Before Wenhui began her PhD, the Water Green Urban Management (WaterGUM) group at UNSW has already developed a WSUD planning model for multiple stormwater management objectives but had not included flood mitigation. This provided the perfect research opportunity for Wenhui to explore her area of interest. Her research is supervised by UNSW Pro Vice Chancellor Research, Ana Deletic; UNSW School of Civil and Environmental Engineering (CVEN) Research Associate Dr Behzad Jamali and CVEN Senior Research Associate Kefeng Zhang.

Wenhui says that UNSW’s renowned WSUD research team at the Water Research Centre was one of her key reasons for choosing UNSW, along with its top-ranking research in engineering. She says that the culture has been one of the best things about her PhD journey so far.

“I really appreciate the supportive learning environment that UNSW provides,” says Wenhui.

 “In addition, the diverse culture and education backgrounds of researchers at UNSW also provide valuable opportunities to develop a global perspective on multi-disciplinary issues like WSUD planning and flood management.”

Wenhui plans to keep working with and on her model in the future, hoping to participate in planning projects where she can apply the model and further advance its functionalities. She’s also hoping to explore its application in the field of international development where it may help to build sustainable cities in developing countries.