When lifeguard George Lee Song Choo saw a man having difficulties in the Yio Chu Kang swimming pool, he rushed to his aid.

The man, who was in his 60s, was taken to Khoo Teck Puat Hospital, and had suffered a stroke while swimming, it turned out. His left ear, arm and leg were paralysed.

Three months later, he came back to the swimming complex to look for Mr Lee, and to let him know that he was grateful to him for saving his life.

Although the incident happened in 2011, it remains fresh in Mr Lee's mind. He said: "I was so surprised to see him; I could feel tears welling up in my eyes. I will never forget that."

Events such as this are partly why Mr Lee, 62, who worked as a lifeguard at the Singapore Sports Council, continues to volunteer as a lifeguard after retirement in 2012.

He is also president of the Singapore Life Guard Corps, where he has been volunteering since 1972.

The Singapore Sports Council is now called Sport Singapore.

To stay in top shape, Mr Lee goes for a jog and swim almost every morning. For fun, he goes out for the occasional karaoke session.

He said: "I never take my eyes off the water when I'm working. It doesn't matter who's speaking to me, my boss, the king - I must always be looking. "

With 45 years of experience under his life jacket, he is the most experienced lifeguard on patrol at the Changi Point coast. The father of two grown-up children - his son is 34 and his daughter is 31 - has two grandchildren, a 13-year-old boy and an 11-year-old girl.

Mr Lee said he knew he wanted to learn more about being a lifeguard after an incident in his childhood.

He said: "I was about 10. I went fishing in the countryside and I saw a boy struggling in the water, and he was getting no help. In the end, I used my fishing rod to pull him back to safety."

Mr Lee became a qualified lifesaving teacher by 1985, and a Grade 1 life-saving examiner in the 1990s. From 1978 to 1984, when he was in the army, he was a pool supervisor and swimming instructor.

North West District Mayor Teo Ho Pin, who is the honorary adviser to the Singapore Life Saving Society, said "water safety awareness among Singaporeans is low".

Speaking to The Straits Times, he said: "Many Singaporeans are non-swimmers or weak swimmers, and there is a shrinking pool of passionate and experienced life-savers."

Mr Lee said: "Singapore is surrounded by water and yet, many areas and pools do not have enough lifeguards." This is why volunteers are so important, but they are also hard to recruit, he added.

While there are volunteer lifeguards in Changi Point and East Coast Park, he said there are other beach areas that have no lifeguards.

The Singapore Life Saving Society estimates that there have been between 30 and 48 drownings in each of the last six years, except last year, when there were 13 drownings. Half of the drownings and near-drowning incidents involving children take place in condominium pools, most of which do not have lifeguards.

Said Mr Lee: "People don't take water safety seriously. They realise the importance of water safety only when they are facing a situation when they are feeling unsafe in the water."

The solution, he said, is to get people to learn more about water safety. He added that he will teach his two grandchildren life-saving skills. He said: "If I hear of someone drowning, it makes me upset and I want to do something. If more people had that skill, they would feel the same."

Correction note: An earlier version of the article said that Mr Lee became a qualified lifesaving instructor by 1972, and was a chief swimming instructor later. This is incorrect. Mr Lee became a qualified lifesaving teacher by 1985 and was later a swimming instructor. We are sorry for the errors.