Saturday, November 5, 2016

Singapore Has No Natural Water Supply, but the Country Isn’t Going Thirsty

The island nation uses recycled water, desalinization, and artificial reservoirs to meet water demand.


Singapore's Marina Barrage reservoir. (Photo: Public Utility Board, Singapore)


Kristine Wong is a regular contributor to TakePart and a multimedia journalist who reports on energy, the environment, sustainable business, and food.


In just 10 years, two out of three people will be living in a country that’s struggling to meet demand for water, according to the United Nations. But even though Singapore has no aquifers or lakes, it’s unlikely that nation’s 5.5 million residents will be among the world’s thirsty.

That’s because the small island nation, which consumes 400 million gallons daily, has a water strategy that is arguably one of the most successful in the world.

“We have four national taps,” George Madhavan, the spokesperson for Public Utility Board, Singapore’s government agency in charge of water quality, conservation, and supply, said during a recent Meeting of the Minds urban-sustainability conference in California.

The “taps” flow from desalinated seawater, recycled wastewater, water collected from rainfall, and an imported supply from neighboring Malaysia.

Having a reliable source of water has always been on the government’s agenda, Madhavan said.
“Without secure and reliable access to water in Singapore, business will not come,” he said. “So that’s a top priority to get a bigger piece of the pie.”

The push to develop a mostly self-sufficient water supply has been credited to Lee Kuan Kew, the country’s first prime minister, who took on the task in response to water shortages in the 1960s and ’70s.
It wasn’t a quick fix. It took 30 years to put the system in place.

The PUB water agency says its “jewel” is the ability to recycle used water, or wastewater from sinks and toilets, into what it calls NEWater. The NEWater purification process, which Singapore launched in 2003 (after getting tips from the Orange County Water District’s wastewater-recycling plant in Southern
California), meets 30 percent of daily water demand. While the recycled water is mainly used for industrial purposes, it also replenishes the country’s 17 reservoirs.

Recycled water can also supply water for drinking and cooking. According to PUB, NEWater has passed 130,000 scientific tests and exceeds the drinking water standards set by the U.S. Environmental Protection Agency and guidelines issued by the World Health Organization.

Here’s what happens: The wastewater travels through a network of deep tunnel sewer pipes, then goes through conventional treatment at a sewage treatment plant. It’s then either returned to the sea or sent to one of the country’s four NEWater plants for further purification, depending on demand.

The NEWater plants follow a three-step process. First, membranes filter out small particles such as solids and bacteria. Next, reverse osmosis takes out larger contaminants. Last, the water is disinfected with ultraviolet light and hydrogen peroxide.

But Madhavan said the government knew a large part of successfully integrating recycled wastewater to its supply hinged on whether Singaporeans would want to drink it in the first place.


Another quarter of Singapore’s daily demand is met by its two desalinization plants, which together can process 100 million gallons a day. Because the plants are energy-intensive, the country is experimenting with electrodeionization, a process that consumes less power.

The third tap comes from rainwater collected from drains, canals, rivers, and storm water collection ponds. (Residents aren’t allowed to harvest water without the government’s permission.) In combination with water imports from Malaysia, the rainwater fulfills the remaining 45 percent of Singapore’s daily water needs.

PUB is preparing for a projected doubling in demand by 2060. (Singapore’s water agreement with Malaysia is set to expire in 2061.) The agency says it’s on track to triple its NEWater production and build two new desalinization plants that together will meet 80 percent of demand in 2060.

Madhavan said Singapore thinks about water in a different way.
“You don’t want to drain it—you want to collect it,” he said.



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