Singapore seeks sustainable water supply

For a tiny island nation roughly the size of Bahrain or a moderately sized Caribbean island, Singapore has done an astonishing job ensuring it has enough drinking water.

When the island was settled by the British under Sir Stamford Raffles in 1819, its streams and wells were enough to supply its population of 150 people.

But modern Singapore, one of Asia’s fastest-growing financial centres, has a population of more than 5.3m. Not only must they be supplied with drinking water but there is huge need for industrial water to supply the manufacturing industry, which makes up about a quarter of gross domestic product.

Without any hinterland that could provide a steady source of groundwater, Singapore has relied on neighbouring Malaysia for most of its supplies since 1962. That was three years before the two countries ended a shortlived experiment at cohabitation under a single political federation.

When that ended in acrimony – resulting in the establishment of an independent Singapore by then-prime minister Lee Kuan Yew – the agreement continued.

Relations between the two countries are better than they have been for decades, largely thanks to a good relationship between their two prime ministers.

But for the past half century, Singapore has been acutely aware of the political risks associated with being dependent on another country for its water supply – and has sought to diversify its sources. That has involved a combination of ingenuity and capital expenditure on a scale probably unrivalled in the world.

Under a “Four National Taps” policy, water is generated from four sources. While more than half comes from Malaysia, the shortfall is made up from desalinated seawater, water catchments and a massive purification programme implemented in 2003 called NEWater.

“Singapore has developed a pragmatic vision, long-term planning and action frameworks that have allowed it to move from vulnerability into sustainability,” say the authors of a new book entitled The Singapore Water Story.

Kishore Mahbubani, dean of the Lee Kuan Yew school of public policy at the National University of Singapore, puts this achievement in a personal context in the book’s foreword, saying that Singapore was a typical third world city when he was a child growing up there in the 1950s.

“We had no flush toilet at home. Today, virtually every home does,” he writes.

Singapore has two separate systems to collect rainwater and used water. Rainwater is collected through a comprehensive network of drains, canals, rivers, stormwater collection ponds and reservoirs before it is treated to become drinking water.

This makes Singapore one of the few countries in the world to harvest urban rainwater on a large scale for its water supply. Since 2011, the water catchment area has been increased from half to two-thirds of the island’s surface.

More remarkable is a so-called deep tunnel sewerage system, which consists of two large, tunnels crossing the island, two centralised water reclamation plants, deep sea “outfall pipes” and a sewer network.

At the heart of that system is a water reclamation plant near the national airport capable of treating the equivalent of 320 Olympic-sized swimming pools of used water a day to international standards.

The treated used water is then discharged into the sea through deep sea pipes or channelled to a NEWater factory on the rooftop of the reclamation plant where it is further purified through advanced membrane technologies into NEWater, which is pure enough to be bottled for drinking.

Completion of the deep tunnel project is supposed to halve the amount of land taken up by used water infrastructure, according to the Public Utilities Board (Pub), the government agency that manages Singapore’s water.

Water demand in Singapore is about 400m gallons a day, with homes consuming 45 per cent and the non-domestic sector taking the rest. By 2060, total demand could almost double, according to the Pub. The non-domestic sector could account for about 70 per cent of that.

The challenge for Singapore will be to meet that demand as the city state’s overall population continues to grow. Government projections say the population could reach 6.9m by 2020, with some of that coming from a gradual increase in the number of foreigners being accepted into the community to help offset a low birth rate.

Without some level of continued immigration, Singapore is unlikely to be able to keep growing, ministers have said, even if planned worker productivity improvement measures implemented last year succeed.

That means even more water will be needed. With 17 reservoirs, 32 rivers and more than 8,000km of waterways within a space of 700 sq km, Singapore has already built much of the infrastructure.

Yet as The Singapore Water Story points out, the country is still faced with costly development of infrastructure, as different government agencies compete for scarce land for various purposes.

On the supply side, the Pub says Singapore is “on track” to more than triple NEWater capacity and ramp up desalination. Together, these are estimated to be able to meet up to 80 per cent of water demand by 2060.

The private sector – including foreign companies – is playing an increasing role. Last month, Meiden, a Japanese company, opened Singapore’s first water recycling plant using “ceramic membrane” technology.

The pilot project is designed to establish whether the technology, which recycles industrial waste water into reusable water for factories and other industrial users, can be expanded on an economical basis to account for a greater proportion of the supply of industrial water.

It is also part of an effort to develop Singapore as a “global hydrohub”, according to Lim Kok Kiang, assistant managing director at Singapore’s Economic Development Board, which oversees inward investment.

“This investment by Meiden is testimony to how companies can leverage Singapore as a living laboratory to develop, test and commercialise innovative industrial water solutions,” he says.

Yet in spite of Singapore’s progress towards self-sufficiency in water, it remains dependent on Malaysia.

A reminder of that dependency came only last month when reports surfaced in the Malaysian media that Kuala Lumpur might be considering charging its neighbour more for the water it supplies.

That prompted Singapore’s foreign minister to remind the Singapore parliament that “neither party can unilaterally change any of the terms of the 1962 water agreement”.