The Singaporean Government is spending 10 billion SGD (7.2 billion USD) to complete an underground sewer system in the city state.

A desalination plant in Singapore's western Tuas district, is part of the city-state's effort to raise its self-sufficiency in water. (Photo: asia.nikkei.com)

The underground superhighway is 3-6 metres in diameter, and is installed at a depth of 35-55 metres. It will collect wastewater from households and factories, and transport it to treatment plants. Post-treatment water will be used mainly for industrial and air-con cooling purposes.

According to Ng Joo Hee, chief executive of the Public Utilities Board, used water is a source of good water, and it should not be wasted.

The approximately 90 km-long tunnel line, which is scheduled for completion by 2025, is meant to increase the ratio of recycled wastewater to total water demand in Singapore from current 40%.

The Singaporean government hopes to meet up to 85% of demand with wastewater recycling and seawater desalination by 2060.

As a water-scare nation, Singapore is investing heavily to raise its water self-sufficiency rate because it has periodically faced pressure over the issue from neighbouring Malaysia, which has traditionally supplied it with much of its water.

(Source: VNA)