• Urban innovator Nadeesha Chandrasena on her award-winning engineering solution and the importance of following your passions

The Lankan flag flying high abroad is always exciting to witness, and last week saw Sri Lankan innovator Nadeesha Chandrasena recognised at the Australian Good Design Awards for her Smart Drain – a dual channel drainage system that can be retrofitted onto existing drains and prevent drainage clogs, ensuring uninterrupted water in severe weather conditions. 

Her innovative work recently earned her two prestigious accolades at the 2024 Australian Good Design Awards: a Gold accolade in the Engineering Design category and, unexpectedly, the ‘Best in Class’ award. 

The Sunday Morning Brunch sat down with Nadeesha following her Good Design Awards wins for a chat on how she developed the Smart Drain and its implications. 

Speaking about being recognised by the Australian Good Design Awards, she shared that she was feeling incredibly excited to have been recognised. 

“To be honest, I applied at the last minute. I saw a LinkedIn post about it in May on the last day of applications. I went for it and applied, and they asked me to hand over a prototype of my design in July, which I did,” Nadeesha shared. 

“Then on 9 August (which was my birthday) I received an email saying I had won a Gold accolade in the Engineering Design category (the Good Design Awards has 32 categories). The ‘Best in Class’ award was a complete surprise and was announced at the event. I never expected to win.” 

A drain gain

The Smart Drain is Nadeesha’s solution to managing urban flooding, a growing problem worldwide, especially in rapidly developing cities with ageing or inefficient infrastructure. 

As an urban innovator and civil engineer, Nadeesha’s solution, the Solid Waste Clog-Resistant Smart Drain uses patented mechanical and digital technology to prevent solid waste like plastic and other waste from clogging drains. This in turn helps avoid (or at the very least minimise) flash floods caused by clogged drains in urban settings where such floods can disrupt transportation, damage property, and even lead to loss of life. 

Nadeesha shared that what most impressed the Good Design Awards jury was the impact the Smart Drain could have on overall urban stormwater management. 

“The jury commented that the Smart Drain was ‘a prime example of engineering design excellence, addressing a critical problem with innovative and out-of-the-box thinking. It demonstrates how technical ingenuity can lead to significant improvements in urban infrastructure,’ which was very inspiring to hear,” she said. 

The Smart Drain is a breakthrough in urban stormwater management in terms of how it augments existing drainage systems’ abilities. Traditional drainage systems are prone to clogging when solid waste such as plastic, leaves, and other debris get trapped inside. This problem is particularly acute during periods of heavy rainfall, as debris significantly reduces the drainage capacity of the system. 

“Think of drainage systems as a human heart,” Nadeesha explained. “Just like a human heart, when arteries get clogged with cholesterol, it leads to a heart attack. The same thing happens with storm drains in cities when they get clogged by floating waste.”

The Smart Drain system is designed to prevent these blockages. It features a world-first, patented dual-layer structure: the upper layer traps solid waste, while the lower layer allows stormwater to pass through unimpeded. 

“When doctors perform a bypass on a human artery, they ensure blood circulation continues despite blockages,” said Nadeesha. “I did something similar for city drains. Instead of allowing a complete bypass, I created a secondary channel within the drain to ensure free water flow.”

This innovative solution is both practical and efficient, and can be easily retrofitted into existing drainage systems. Using 3D printing, the upper part of the drain can be customised with mesh baskets and sensors. The sensors, which are designed to be affordable and resistant to vandalism, monitor the fill levels of the baskets and alert authorities when they need attention. 

“The system can send real-time updates when the baskets are 50%, 70%, or 90% full, allowing for timely intervention,” she added. Additionally, flow velocity sensors can detect anomalies in the water’s movement and act akin to an early warning system. 

This blend of smart technology and practical engineering makes the Smart Drain not only effective at managing stormwater but also provides a scalable solution for urban areas prone to flooding.

The bigger picture of urban resilience

Nadeesha’s background comes from being an urban planner. By and large, urban planners are meant to play a pivotal role in making cities more resilient to climate change, extreme weather events, and other environmental challenges. 

“Urban planners help shape cities, ensuring they are designed to withstand disasters,” she explained, adding that urban planners were also meant to plan cities for resilience, whether directly or indirectly, and not just in terms of physical structures but also in terms of social, economic, and environmental sustainability.

“The scope of urban planning is vast; I place myself within it as an urban innovator. Within the scope of urban planners, there are many roles a planner can play – some can work as policy planners, some in design, some in the implementation area, in administration, or in R&D,” Nadeesha shared. “I work within urban innovation as an urban inventor – I create new solutions.” 

As an urban innovator, she takes it upon herself to create urban systems that can adapt to changing conditions. This was what led to her developing the Smart Drain, a small but significant piece of this larger puzzle. She emphasised that stormwater management systems needed to be adapted to the specific needs of each location. 

“Every drain design should be unique to the place it is installed,” she noted. “You can’t generalise solutions, because the needs of one location will differ from another based on geography, the local environment, and human activity.”

As a tool that integrates seamlessly into the larger framework of resilient, sustainable city planning, Nadeesha sees the Smart Drain as a tool that can be used in any manner. In fact, one of the projects she is most passionate about at the moment is an initiative she has coined as the ‘Build Your Own City Drain’ initiative, which aims to provide cities with free Smart Drain systems through crowdsourcing and community involvement. 

“I’m building a pro bono resource collective,” she explained. “We’re asking contractors, engineers, and other professionals to team up and work together to build these drains using their own resources.”

The concept behind this initiative is similar to ‘shramadana’ – a traditional Sri Lankan practice in which communities come together to complete a project for the common good. In this case, Nadeesha envisions communities working together to solve their drainage problems, constructing Smart Drains in high-risk areas to reduce the risk of flooding. 

“We need permission from the Government, but other than that, we can start working on it,” she added.

This project not only addresses an urgent infrastructure need but also fosters community empowerment and collaboration. By involving local stakeholders in the construction of their own drainage systems, Nadeesha is hoping to build a framework which can in turn build stronger, more resilient communities.

Pursuing your dreams

Brunch also talked to Nadeesha on her experiences as a woman in STEM (Science, Technology, Engineering, and Mathematics). As an award-winning urban innovator, Nadeesha initially studied biosciences and qualified as a town planner before pursuing a Master’s in water management and then completing a PhD in civil engineering focusing on open-channel hydraulics. 

“I don’t have a fully-fledged engineering qualification,” she admitted. “I have a little  engineering knowledge, but I’m happy and proud to say I’m an urban planner and an urban innovator.”

This career path can seem unconventional given that you often don’t hear about women in STEM, but Nadeesha was quick to dispel this, pointing out that STEM was a huge field that saw plenty of women in it. 

“This is the IT era,” she said. “It’s not a big deal for women to select engineering or any other field. You can select anything you’re passionate about and work on a dream. It’s not about whether you’re studying rocket science or something like that; it’s about putting your passion into that field and making a difference.

“Motivating girls to pursue education and careers in STEM is amazing, yet it’s crucial to understand that selecting a path in these fields does not automatically equate to success or fulfilment. Often, societal pressure can lead girls to enter STEM based on external expectations rather than genuine passion, which can be counterproductive,” Nadeesha said.

In addition to following their passions, Nadeesha encourages young women to look to trailblazers who have redefined what’s possible for women in their respective fields. 

She cites cultural icons such as Sri Lanka’s first professional female dancer Vajira Chitrasena, the world’s first female Prime Minister Sirimavo Bandaranaike, and entrepreneur Aban Pestonjee, who started her business in a garage at the age of 28. These women, Nadeesha said, demonstrated that success was achievable in any field, provided you had the courage and determination to pursue your goals.

“Each of these women left an indelible imprint on society,” Nadeesha noted, highlighting that each of them was known as a trailblazer because they didn’t just follow a path set out for them; they created their own path, inspiring future generations to follow their dreams.

Greatness lies in following one’s true passion, not in conforming to societal expectations. “Every dream is important,” she said. “Each aspiration, whether in STEM or elsewhere, offers unique perspectives and innovations that can shape our world for the better.”