Professor Lee Seng Lip still goes to the office up to four times a week, plays golf twice a week, attends functions and swims.
He is 88, yet the veteran engineer maintains a busy schedule and keeps his mind occupied.
"I do not teach any more but I go to engineering events and I still read," he said. "I make sure my brain remains active."
Prof Lee has given more than four decades of his life to the profession.
He has worked in infrastructural engineering here, both in education and practice, and is also an expert in structural, geotechnical and construction technology.
The sprightly octogenarian, who has almost perfect eyesight, attributes his longevity and perseverance to passion.
"I like the discipline. I like the job, I like what is involved. I like studying to improve myself."
He earnestly claims he has "never been stressed" by his job.
"People are stressed by things they cannot do. I never let myself be in that position," he said, explaining that he treats every structural or construction engineering problem that he comes across as a positive challenge.
These days, he works as a consulting engineer. The emeritus professor can either be found in his office at the National University of Singapore (NUS) or out giving his expert opinion on an engineering project.
For all his accomplishments, he was recently presented with the inaugural Institution of Engineers, Singapore (IES) Lifetime Engineering Achievement Award.
The award recognises an outstanding engineering leader, whose lifetime achievements have made a profound impact on the industry and who has brought honour to Singapore.
Prof Lee, who said he is "deeply honoured" by the award, showed inclination towards the discipline in his teenage years, when he built a kitchen and garage for his older brother without formal training.
At university, he started out studying architecture and engineering as he had an interest in both, until a professor pointed out to him that he lacked creative flair and encouraged him to concentrate on the latter.
"In architecture, one needs to be artistic," said Prof Lee. "I realised I was more scientifically inclined."
Since pursuing engineering, he has not looked back and many accolades have followed.
The American joined NUS in 1975 and served as the head of its civil engineering department until 1989.
As an academic, he has published more than 500 papers in international and regional journals.
Prof Lee's colleague in the faculty of engineering, Professor Cheong Hin Fatt, recalls him being "very serious" about his work, and collaborating with him late into the night on various projects.
Prof Lee has taught thousands of students, many of whom are now fellow professors or respected practitioners in the field.
Former IES president Tan Seng Chuan is one such individual. "Prof Lee made the subject interesting," he recalled. "His lectures were enjoyable because he would tell jokes. People like him inspire the young to take up engineering."
As a practitioner, Prof Lee has left his imprint on Singapore's infrastructural landscape.
He recalls how he suggested a construction method for the Changi Airport control tower, which allowed it to be completed under tight deadlines.
He also gave advice on how to ensure structural integrity in the construction of the sloping sides of Marina Bay Sands, and made cost-saving suggestions during the expansion of Jurong Point shopping mall.
Dr Chew Soon Hoe, an IES council member, described Prof Lee as an "innovative visionary".
Referring to his patent of fibre drains for soft clay treatment, which is used extensively in reclamation projects, Dr Chew said: "It was the first NUS patent, more than 25 years ago. It is biodegradable and made out of recycled material. He invented this long before society was talking about environmental friendliness and sustainability."
This method was successfully used to reclaim 40ha of land at Changi South Bay.
Prof Lee's acumen is highly sought after in overseas engineering projects, in countries including Japan, Indonesia and China.
He recalls recently telling a company in Singapore not to get involved in a particular development overseas, as he sensed it was a scam. "One look and I knew the developer was insincere so I said, 'Don't go into it'," he said.
"I advise not for money, but to do the right job for society."
When asked about his proudest achievement, he did not name any structure that is a part of Singapore's skyline.
Instead, he said: "I'm proudest of the fact that I've educated many engineers, who have contributed to the infrastructural development in Singapore and South-east Asia."
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