A Love Of Waterways

PUB Chairman Mr Tan Gee Paw has helped Singapore turn her freshwater scarcity from a vulnerability into a strength.

SG50 banner for web

AsianScientist (Sep. 18, 2015) – Singapore ostensibly has lots of water. It falls freely from the sky, and surrounds the tropical island in voluminous quantities. But for decades, these two sources remained out of reach to its people, who had no means to capture or purify it in an efficient manner.

In the 1960s, Singapore was almost entirely dependent on imported water from Johor, Malaysia’s bordering state. Droughts and floods made water a collective concern of this young nation, an existential threat. For instance, a particularly severe drought in 1963 led to a ten-month rationing period, during which it was common to see long queues at public water taps.

Over the subsequent five decades, Singapore embarked on a relentless drive to achieve water self-sufficiency, led by Lee Kwan Yew, its first prime minister. It built up water catchment areas, modernised sewerage systems, cleaned up waterways, and introduced innovations in water recycling and desalination.

Few people are as intertwined with Singapore’s water narrative as Tan Gee Paw, chairman of the Public Utilities Board (PUB).

Every drain and canal in Singapore

Mr Tan’s career began as a junior engineer at the Public Works Department (PWD) in the late 1960s, but only after a last minute change of heart.

Having won a Colombo Plan scholarship to study marine engineering, Mr Tan was en route to the Public Service Commission (PSC) to complete the necessary paperwork.

Feeling pensive, he stopped by Clifford Pier to look at bumboats, which used to carry cargo back and forth between the warehouses and ships before the arrival of modern containerisation technology.

Although grateful for the scholarship, Mr Tan was not sure if marine engineering was the right course.

“I remember sitting on the parapet wall overlooking the sea, with my legs dangling out there,” he says. “I just pictured myself as a marine engineer on board a ship, and I said, ‘How could I spend my life that way?’”

Mr Tan eventually made it to PSC’s office at the Fullerton Building, where he declined the
scholarship. He later successfully applied for a PSC bursary to study civil engineering at the University of Malaya.

Returning in 1967 to serve a four-year bond, Mr Tan met the PWD’s director, Hiew Siew Nam, who informed Mr Tan that he would be posted to the drainage department.

“My heart sank,” he says, “Because if you’ve done well in your studies you expect to be building bridges, something to show off … Buildings, skyscrapers, funny structures, long structures, and things like that.”

Adding salt to the wound, PWD gave him a maintenance role within its drainage department, instead of one of the more coveted positions in design and construction.

However, serendipity came knocking in 1971. Mr Lee had just set up the Water Planning Unit in the Prime Minister’s Office. He asked Mr Tan, who by then had an intimate knowledge of every drain and canal in Singapore, to plan the country’s longterm water supply.

In those days, to get a single, statistically relevant figure, a hydrologist had to record a daily
inventory of water rainfall and draw-out—input and output, respectively—from every reservoir over a period of fifty or more years.

Mr Tan knew that a computer simulation could generate the same data within minutes. In the 1970s, PWD had a room-sized ICL 1900 series mainframe computer that they used to print their bills. With the help of the unit’s manager, Lau Peng Sum, Mr Tan built mathematical models using a computer programming language called Fortran, short for Formula Translating System.

“I would go in at night with stacks of punch cards… I think it is very archaic to you all now,” he says, recalling the work he did to complete Singapore’s First Water Masterplan.

In 1974, Mr Tan joined the Ministry of the Environment as an engineer in its environmental engineering division. His job entailed, among other things, working with the same bumboats, which by then had become the Singapore River’s main pollution source.

The river then was like an open sewer, its stench pervading for miles away. Bumboat residents defecated into the river, whose banks were crowded with illegal squatters and hawkers jostling for a sale.

At the opening of Peirce Reservoir in 1977, Mr Lee challenged the Ministry of the Environment to clean up the Singapore River: “In ten years, let us have fishing in the Singapore River and Kallang River.”

Working with Lee Ek Tieng, then permanent secretary of the Ministry of the Environment, and a team of dedicated officers, Mr Tan chaired an interagency committee of 11 government departments, which successfully cleaned up the Singapore River. The decade-long project won the team the Clean Rivers Commemorative Gold Medal in 1987.

Two new water taps for Singapore

By 1995, Mr Tan had become permanent secretary of the Ministry of the Environment. He led the reorganisation of PUB from a utilities provider into a national water agency that manages the whole water cycle—from water supply, to drainage, to used water and water reclamation.

He joined PUB as chairman in 2001, where he helped to turn on two additional “water taps” for Singapore—recycled used water and desalinated seawater—which supplemented the country’s two older sources (local catchment and imported water from Johor).

To recycle either used water or seawater, a technology called reverse osmosis is used. In osmosis, water moves from a state of higher to lower osmotic pressure across a semipermeable membrane. In reverse osmosis, conversely, applied pressure pushes water against this osmotic gradient, producing clean water and leaving both salts and pollutants behind.

In the 1970s, though the concept of recycled water was around, membrane technology was not advanced or cheap enough to scale up. PUB’s first reverse osmosis plant in Ulu Pandan was too expensive and its equipment kept breaking down. It lasted just two years.

By the 1990s, membrane technology had improved significantly. PUB opened its first used water recycling plants in Bedok and Kranji in 2003.

Public opinion was on its side, Mr Tan says, citing a survey that showed 95% of Singaporeans were in favour of the technology. All the test results underscored the public’s belief. NEWater—Singapore’s brand of ultra-clean, high-grade reclaimed water—exceeded the drinking water standards set by the US Environmental Protection Agency and the World Health Organization.

“The first time I saw NEWater, it was kept in a well about two stories deep at Bedok, lined with concrete all the way round,” Mr Tan says. “The water was sparkling, crystal clear.”

Since its introduction in 2003, NEWater has been used mainly for industrial purposes such as wafer fabrication, freeing other sources for residential use. The same membrane technology also made it possible for the Marina Barrage to be built in 2008, creating an expansive freshwater reservoir in the city that meets 10% of Singapore’s water needs.

The fourth water tap, desalinated seawater, was also a priority for Mr Tan. In 2005, PUB introduced Singapore’s first desalination plant at Tuas, in a public-private partnership project with SingSpring Pte Ltd.

In 2013, PUB and Hyflux Ltd, a pioneering Singaporean water technology firm, opened Tuaspring Desalination Plant, Singapore’s second desalination plant and also its largest. Hyflux is now building the world’s largest seawater desalination plant in Algeria.

From vulnerability to strength

Mr Tan’s thoughts turn to the 1961 and 1962 Water Agreements with Malaysia, which have guaranteed Singapore access to subsidised fresh water—while also making the tiny country reliant on its much larger neighbour. He says that by the time the second water agreement expires in 2061, PUB plans to have tripled NEWater capacity to meet up to 55% of Singapore’s water demand, while desalination will account for another 25%. And the remaining 20%? “Free from the sky,” he says with a laugh.

In addition, Singapore is positioning itself as a global “hydrohub” where innovative water research takes place. To date, Singapore’s National Research Foundation has invested close to half a billion dollars in water-related research projects via the environment and water industry programme office.

More than 180 water companies and 26 research institutes have set up base in Singapore. In addition, Singapore-based companies have secured well over S$10bn worth of overseas projects in the last ten years.

A recipient of the prestigious Stockholm Water Industry Award in 2007, PUB is collaborating with academic researchers to investigate futuristic biomimetic technologies—designs that are adapted from nature to solve modern problems.

“How does the mangrove swamp desalt seawater? How do some freshwater fish survive in brackish water? The kidneys do it very easily too,” Mr Tan says, referring to proteins called aquaporins, which control the water content of biological cells in both plants and animals.

Where water management is concerned, rising sea levels from climate change may lead to yet another existential crisis for Singapore. Mr Tan sits on Singapore’s Climate Change Network committee, which explores ways to mitigate the risks involved.

As a young engineer in the maintenance section of the drainage department, Mr Tan may not have predicted that he would receive the 2007 President’s Award for the Environment and honorary doctorates from British and Singaporean universities.

But for someone whose lifelong passion even seeps into his hobby of oil and acrylic painting, it is well deserved.

“Most of the landscapes that I paint will always have some water in it,” he says. “They are very quiet, placid, waters. I love waterways.”

This feature is part of a series of 25 profiles, first published as Singapore’s Scientific Pioneers. Click here to read the rest of the articles in this series.


Copyright: Asian Scientist Magazine; Photo: Bryan van der Beek.
Disclaimer: This article does not necessarily reflect the views of AsianScientist or its staff.

Juliana is the founder and CEO of Wildtype Media Group, Asia's leading STEM-focused media company, spanning digital, print, custom publishing and events. Brands under Wildtype Group include Asian Scientist Magazine and Supercomputing Asia, award-winning titles available in print and online. Juliana regularly moderates panel discussions and gives talks on science communication.

Related Stories from Asian Scientist