Singapore took another step towards boosting its water security in the face of climate change by opening its fourth desalination plant - the only one capable of treating sea and reservoir water.
Speaking at the official opening of the Keppel Marina East Desalination Plant yesterday, Prime Minister Lee Hsien Loong said weather conditions are set to become more volatile and it will become harder for Singapore to ensure a stable and reliable water supply.
He cited how Malaysia's Linggiu Reservoir, where Singapore draws a significant proportion of water from, had plunged to 20 per cent of its capacity - a historic low - during a dry spell in 2016. While the situation has improved with recent rain, he said: "I was really worried, and tracking the situation daily, because there was a real risk to our water supply. It was a vivid reminder of why we have to be obsessed with saving water, and make every drop count."
Singapore consumes 430 million gallons of water a day, a figure that is expected to double by 2060.
"Local catchments and water imported from Malaysia are already insufficient to meet our daily needs," PM Lee said. But Singapore has supplemented its supply with recycled used water and desalination.
The Keppel Marina East Desalination Plant, which started operating last June, is the country's fourth such facility to come on line.
National water agency PUB's chief executive Ng Joo Hee, who was also at yesterday's event, said desalination - or the conversion of seawater into drinkable water - is one of the four national taps. "Unlike the other three taps - imported water, rainfall and recycled water - (the sea) is a practically limitless resource."
The plant can treat about 30 million gallons a day (mgd), or up to 7 per cent of Singapore's daily water needs of about 430mgd.
The 2.8ha facility, located between East Coast Park and Bay East Garden, can draw water from the sea during periods of dry weather, or treat water from Marina Reservoir during periods with heavy rain.
It is the first large-scale desalination plant with both these features, and was built following years of testing and research, including a 2007 test of dual-mode desalination at a demonstration plant in Pasir Ris.
Mr Chew Chee Keong, PUB's director for water supply (plants), said the facility, located right by the coast and next to Marina Reservoir, is in a good position to harness both sources of water.
"With climate change... we are likely to experience more intense rainfall and more severe drought. (The plant's) dual-mode function affords PUB greater operational flexibility to respond to the vagaries of weather, strengthening Singapore's water supply resilience."
Water expert Asit Biswas, a distinguished visiting professor at the University of Glasgow, said it may not be feasible for all desalination plants here to have this dual function, as many are located at sites such as Tuas, which do not have access to freshwater.
"That said, where the pre-conditions of access to both freshwater and seawater are met, like in the case of (the new plant), dual-mode capability is an attractive option that could be considered," he added.
PUB said the fifth desalination plant on Jurong Island, which was slated to open last year, has been delayed due to the Covid-19 pandemic, but it is expected to be completed by the first half of this year.
As for the Tuas South Desalination Plant - which PUB took over from embattled water treatment firm Hyflux in 2019 - it can produce drinking water even while repairs to address operational issues are ongoing, Minister for Sustainability and the Environment Grace Fu said in a written reply to a Parliament question from Aljunied GRC MP Gerald Giam on Monday.
She said: "The repairs, which included the replacement of ultra-filtration and reverse osmosis membranes, cost around $80 million in total and are on track for completion in mid-2021."