PRIME Minister Lee Hsien Loong unveiled a massive water treatment complex on Tuesday that symbolises Singapore's green policy, land-use approach and drive towards water self-sufficiency.

The $3.65 billion plant in Changi, connected to an underground tunnel system, will free up nearly 1,000ha of land now occupied by older plants in places such as Bedok and Seletar.

This land, to be developed for other purposes, is roughly three times the size of the Central Business District.

The Changi building will have a Newater plant built on its rooftop to turn the treated used water into water safe enough to drink.

When ready next year, the Newater plant, with the existing four, can double Newater capacity to meet one-third of Singapore's water needs.

In Singapore, the approach involves a network of underground tunnels that will pipe waste water from all over the island to two centralised treatment plants.

The Changi plant is the first in this deep tunnel sewerage system. A second plant in Tuas will be built over the next 10 to 20 years. The Changi plant can treat 800,000 cu m of used water, piped daily from the northern and eastern parts of Singapore. This will form a vital feedstock for the Newater factory.

The ultimate goal is to have an adequate supply of water for Singaporeans for years to come, he said.

Singapore imports 40 per cent of its water from Malaysia under two international agreements, one expiring in 2011 and the other in 2061. The rest of its supply comes from Newater, rainwater capture and desalination.

The plant is part of Singapore's overall strategy for sustainable development, showing that environmental sustainability is not incompatible with economic development.

Read the full story in Wednesday's edition of The Straits Times.

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