Monday, 11 July 2016

How Singapore will never go thirsty

By Ng Joo Hee, Published The Sunday Times, 10 Jul 2016

We have to accomplish three things so that Singapore will never go thirsty: Overcome scarcity, reduce the cost of production, and ensure long-term sustainability of our water system.


Although we are right on the equator and smack in the tropics, nature does not provide us with quite enough water to get by. Our small size means there is just not enough room in Singapore to catch and keep all the rainwater we need.

We are in good company though. Big cities are invariably compelled to bring water from without to quench the thirst of their citizens within. Hong Kong, London, New York and Tokyo all draw much, if not the entirety, of their supply from large forest watersheds and rivers well outside of city limits.

The Separation Agreement, which formalised Singapore's independence after it separated from Malaysia in 1965, guarantees us the right to extract 250 million imperial gallons a day (mgd) of raw water from the Johor River. This right expires in 2061. In order that we are able to exercise this right in a sustainable way, PUB, Singapore's national water agency, constructed and operates a large regulating reservoir - the Linggiu Reservoir - in the upper reaches of the Johor River. Water imported from Johor can easily satisfy half of Singapore's current 430mgd daily demand. Unfortunately, dry weather and large discharges to combat salinity intrusion downstream are causing Linggiu to deplete at an alarming rate. Linggiu started last year 80 per cent full but, as I write, its water level has dropped progressively to an unprecedented 31 per cent.

Johor Baru itself suffered several bouts of water shortages recently and was forced into curtailing supplies to its residents each time. PUB's additional provision of treated water had helped many Johoreans this past Ramadan.

It is possible that Linggiu may fail, compromising the viability of the Johor River source and the reliability of imported water. If and when that happens, there should be no panic in Singapore. Over the years, our decision-makers, planners and water engineers have created enough indigenous capacity to meet just such a contingency. This capacity comes in the now familiar forms of NEWater and desalinated water.

The point is this: Singapore, although water-poor, has through foresight, careful planning, determined research and diligent implementation, significantly overcome the challenge of water scarcity. And that is no mean feat.


Rain is free, and making it drinkable is fairly cheap. Desalination and manufacturing NEWater are far more expensive ways of producing potable water. It takes just 0.2 kilowatt hours of energy to treat one cubic m of rainwater, compared to the 1kWh/m³ to turn sewage effluent into NEWater and the whopping 3.5kWh/m³ required to de-salt seawater. Quite obviously, the latter two "manufactured" sources of water supply, although weather-resistant, are capital- and energy-intensive and correspondingly costlier.

Even then, Singapore's water future lies, without a doubt, with re-use and desalination. We estimate that NEWater and desalination together will have to provide for 85 per cent of Singapore's water needs come 2061 when imports cease and demand is double today's.

So PUB possesses every incentive to find new and better means of desalinating seawater and reclaiming waste water in order to continually lower our cost of production.


Deep sewerage tunnels are one of these ways. At the turn of the millennium, waste water re-use technology, principally through the use of reverse osmosis, had become practicable and gave us the opportunity to produce ultra-high-quality recycled water on an industrial scale. This of course meant that sewage was not just waste water any more, but would become a major source of potable water for us. These developments drove Singapore to become one of the earliest adopters of a deep tunnel sewerage system (DTSS).

The initial portion of Singapore's DTSS was completed in 2008. Unbeknown to most, deep inside the ground is a 6m-wide tunnel that criss-crosses Singapore from Kranji to Changi. Along the way, with the help of gravity, it silently picks up and delivers a tremendous amount of sewage.

At the end of its 48km traverse near to Changi Airport, the DTSS tunnel reaches 50m - more than 20 storeys - underground and shifts nearly a million tons of waste water a day. Massive pumps bring the sewage to the surface to be treated in the Changi Water Reclamation Plant. The resulting effluent is then moved to the neighbouring Changi NEWater factory and further polished to potable quality.

PUB is busy preparing to commence the second leg of the Singapore DTSS, this time running another large sewerage tunnel from downtown westwards all the way to Tuas. When this is completed in a decade, the two tunnels joined up, and state-of-the-art water reclamation and NEWater plants brought online at Tuas, PUB will, literally, be able to collect every drop of waste water and turn it into sweet water again, achieving our aim of endlessly recycling the H2O molecule.

Singapore's DTSS is a marvel of modern engineering, allowing us to efficiently convey a whole country's worth of sewage at minimal expense. It is also a terrific example of how science and new technology, combined with ingenuity and determination, have allowed us to greatly reduce the cost of water husbandry.


What was scarce may be turned into plenty; what was costly can also be made inexpensive. But how do we keep it going? Long sustainability dictates that our water system must endure, and not become too delicate or cumbersome to operate after a time.

There is rain. Rain falls and becomes storm water. Storm water is collected in drains, channelled to reservoirs and stored. Stored rainwater is made potable and supplied to people, commerce and industry.

As PUB supplies good water, water that has been used is returned to us. That used water is collected, treated and turned into good water again, ready to be consumed or squirrelled away in reservoirs. At the same time, seawater is de-salted, turned into good water and fed into the loop.

The water loop is simple enough, but it is still the norm that it be administered in separate pieces. In most places, the water department is separate from the sewerage department, which is separate again from the drainage department. And invariably, all three will work at cross-purposes.

Singapore's secret to a sustainable water supply, however, is to manage the entire water system as an integrated whole. For PUB, supplying good water, reclaiming used water and taming storm water are three legs that hold up a unitary mission.

Looking ahead, climate change is, quite conceivably, the biggest threat to the continued sustainability of Singapore's water system. Global warming, permanently elevated sea levels, and alternating drought and deluge will eventually destroy our water infrastructure if we choose to sit on our hands.

We have to assess and be prepared for a distinctly riskier future. And there is certainly no time to waste in implementing the necessary adaptive and mitigatory measures that will safeguard our water supply system from the climate effects to come.


Despite severely limiting geographic constraints, today's Singapore is not short of water. We can be confident that the country will continue to be water-sufficient in the long run. This makes Singapore unique and the subject of close study by the many thousands who are now convened in our city-state for the Singapore International Water Week this week.

Because we cannot afford to be caught without enough water, or have sewage overflowing onto our streets, or floods inundate our city, Singapore takes an uncommonly long view when it comes to water management, planning decades ahead. Indeed, for as long as we remain clear-eyed and hard-nosed about our country's water situation, and execute our water strategy relentlessly, there should always be enough water.

The writer is chief executive of PUB, Singapore's National Water Agency.

The Singapore International Water Week is from today to Thursday. It is a global platform to share and co-create innovative water solutions.

S$200 million funding boost for Singapore’s water industry over the next five years
This is to ensure it has enough water to cope with effects of climate change
By Carolyn Khew and Cheryl Teh, The Straits Times, 12 Jul 2016

To mitigate the effects of climate change and ensure that Singapore has enough water, the Republic is pumping $200 million into water research over the next five years.

Prime Minister Lee Hsien Loong, announcing the funding at a dialogue yesterday, said research and development have helped ensure an adequate supply of water for Singapore over the years and the country will continue to spend on them.

"Droughts are going to be a problem for us in Singapore. We have to prepare for our own water supply which, for us, has always been a strategic and high-priority issue, and we are putting a lot of resources into it," he said at the Lee Kuan Yew Prize Award Ceremony and Banquet at the Ritz-Carlton Millenia.

The Lee Kuan Yew Water Prize and Lee Kuan Yew World City Prize - which recognise excellence in water and urban innovations respectively - were given out respectively to renowned hydrogeologist John Anthony Cherry and Medellin, Colombia, at the event last night.

PM Lee was responding to a question from Professor Chan Heng Chee, who asked if the region was spending enough on infrastructure to mitigate the effects of climate change. Prof Chan chairs the Lee Kuan Yew Centre for Innovative Cities at the Singapore University of Technology and Design.

PM Lee said climate change will bring about more extreme weather, droughts, floods and rising sea levels, and that some of the effects could be felt faster than predicted.

But these can be mitigated. "There are things you can do about these if you have lead time, and the resources and the attention," he said.

While the official forecast of the rise in sea level is 18 inches (46cm) in 100 years, he warned that this could turn out "faster and higher than as predicted".

So new projects will take this into account. The upcoming expansion of Changi Airport, for one thing, will take place on higher ground to guard against rising sea levels.

It is hoped that the water industry will contribute $2.85 billion to Singapore's gross domestic product (GDP) and create 15,000 jobs by 2020, said national water agency PUB and the Economic Development Board.

The latest investment - some 40 per cent more than the previous tranche - will also go towards helping the industry commercialise innovations more quickly and export them overseas, and develop a suitable talent pool.

In total, the Government has committed $670 million to R&D in the water industry since 2006. The industry contributes more than $2.2 billion to Singapore's GDP and has created over 14,000 jobs.

PUB chief executive Ng Joo Hee said: "Singapore today is really the Silicon Valley of water research and we started from nothing... We have invested and built up capabilities and, today, Singapore is one of the handful of places in the world where real cutting-edge research on water is taking place."

Singapore's current water demand stands at about 430 million gallons of water per day and this could more than double by 2060 - with non-domestic water demand estimated to make up 70 per cent of overall water use.

One key area that PUB is looking into is to reduce the energy involved in producing desalinated water or treated seawater. Current technology uses about 3.5 kilowatt hours of energy to desalinate a cubic metre of water, but the aim is to slash this by 70 per cent.

The technologies being looked at by PUB include one by American company Evoqua, which uses a process called electrodialysis to remove salt ions from seawater.

In a push to ensure the sustainability of Singapore's water supply, General Electric (GE) and PUB have a five-year agreement to explore new research opportunities and develop novel water-treatment technologies and R&D projects locally.

Mr Hoshang Subawalla, regional executive for GE Power (Asia-Pacific), said the agreement was a big step towards helping Singapore become water-independent, by increasing the efficiency of the water-purification process in Singa- pore's desalination plants.

2 'green' plants to improve waste treatment efficiency
By Samantha Boh, The Straits Times, 12 Jul 2016

Two giant facilities, to be built side by side, will take Singapore's treatment of waste water and solid waste to new levels of efficiency.

Each will supply resources to run the other and, between them, the two plants in Tuas will be able to treat 40 per cent of Singapore's waste by 2027.

The Tuas Water Reclamation Plant (TWRP) and the Integrated Waste Management Facility (IWMF) will complement each other in such a way that they will be completely energy self-sufficient.

For example, energy generated at the waste facility through the incineration of trash will be supplied to the water treatment plant.

In return, treated water from the water treatment plant will be piped to the waste facility for cooling purposes, for instance.

Food waste and used water sludge will also be co-digested, through a process called anaerobic digestion where micro-organisms convert waste into biogas, which will increase the biogas yield.

The project, which will include the construction of an integrated Newater factory at TWRP, is estimated to cost $9.5 billion in total, and will be the first of its kind in the world.

Details of the two facilities, and upcoming tenders for their design and construction, were announced yesterday by national water agency PUB and the National Environment Agency (NEA).

Mr Joseph Boey of the NEA and project director of IWMF said the co-location of the facilities "marks a new chapter in the way used water and solid waste are managed in land-scarce Singapore".

Together, they can reduce the environmental and land footprint, and maximise the energy recovered from the treated waste, he said.

In fact, the IWMF will produce 1,980,000MWh of energy a year, enough to power more than 400,000 four-room flats.

Only 10 per cent will be retained to operate the two plants, with the rest exported to the grid.

It will also be the first here to process four types of waste: incinerable waste, household recyclables, food waste and dewatered sludge, which are generally treated separately.

Using advanced technologies that minimise the amount of land required, the plant will be able to treat 500 tonnes of waste that can be incinerated per day per hectare, almost double that of existing waste-to-energy facilities.

The energy that can be derived from each tonne of waste will also be 6 per cent to 8 per cent higher.

The first phase of its development will be completed by 2022, and the whole facility is expected to be ready by early 2027.

Mr Yong Wei Hin, director of the Deep Tunnel Sewerage System (DTSS) Phase 2 at PUB, said the co-location of the pair will save 2.8ha of land. According to preliminary studies, it would also save the Government a couple of hundred million dollars, he added.

The PUB plans to implement "new and tested" water treatment technologies at TWRP, which will allow it to produce less sludge and double its energy recovery while consuming less energy than conventional plants.

The Tuas plant, which can treat 800,000 cubic m of water a day, will also be able to treat both domestic and industrial used water separately, turning them into Newater and water for industrial use respectively.

It is an integral part of the second phase of the DTSS that, when completed in 2025, will use gravity to channel used water in the western parts of the island to the plant through deep tunnel sewers.

The entire DTSS is meant to be a superhighway to transport used water from across the country to three coastal water reclamation plants in Changi, Kranji and Tuas.

This will halve the land used to house water infrastructure from 300ha in the 1990s to 150ha.

Fifth Singapore desalination plant in the pipeline
Located on Jurong Island, it will add 30 million gallons of water per day and help country cope with climate change
By Carolyn Khew, The Straits Times, 13 Jul 2016

Singapore will build a fifth desalination plant on Jurong Island to enhance its resilience against climate change.

Expected to be built around 2020, the plant will add 30 million gallons of water per day - or about 7 per cent of Singapore's current water demand of 430 million gallons a day.

The plant was announced yesterday by Minister for the Environment and Water Resources Masagos Zulkifli at the closing session of the Water Leaders Summit held during the Singapore International Water Week. With climate change, there is a need to develop water resources which are weather-resilient and weather-independent, he said.

In the past two years, desalination and Newater plants, which do not depend on rainfall, have helped mitigate the impact of Malaysia's dry weather on Singapore's water supply, he said.

Currently, imported water from Malaysia accounts for about half of Singapore's water needs, while desalination and Newater can meet up to 55 per cent of Singapore's water needs.

Jurong plant seen serving industry

But the Government hopes to increase the latter to 85 per cent by 2060, when the demand for water is expected to double.

National water agency PUB has already awarded a tender to study the development of the latest desalination facility.

Singapore currently has two desalination plants in Tuas.

Its third desalination plant in Tuas will be completed next year, while the fourth in Marina East will be built in 2019 (see graphic).

PUB is exploring the feasibility of co-locating the latest desalination plant with an existing power plant on Jurong Island, said Mr Masagos. This could help to reduce the amount of energy needed to run the desalination plant.

"It's important for us to be close to a power system or power grid. By co-locating, we will be able to use either the steam generator, or the electricity that we can get directly from the power plant," he said.

Associate Professor Darren Sun of Nanyang Technological University's School of Civil and Environmental Engineering said building the fifth desalination plant on Jurong Island will serve water needs in the industrial sector.

This is especially so as the non-domestic sector is projected to account for 70 per cent of Singapore's water demand by 2060, he noted.

Separately, Mr Masagos launched the Singapore Water Academy yesterday. It will provide courses for engineers and technicians in the water industry from Singapore and around the world. Courses are expected to start next year.

Urban and infrastructure consultancy Surbana Jurong and the Singapore Cooperation Enterprise signed memorandums of understanding with the academy yesterday. They will tap the academy's expertise to conduct training for their staff and clients.

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