Singapore's second large seawater desalination plant was officially opened on 18 September 2013 by the prime minister, Lee Hsien Loong.

The 318,500 m³/d Tuaspring plant uses reverse-osmosis technology preceded by ultrafiltration pretreatment.

Desalinated water, which now provides 25% of Singapore's water, is one of the island state's Four National Taps, along with local catchment water, imported water and NEWater, Singapore's own brand of reused wastewater.

Construction of the desalination plant, currently Asia's largest seawater desalination facility, began in July 2011 under a design, build, own and operate model by Singapore-based Hyflux Ltd. The plant supplies national water agency PUB with desalinated water over a 25-year period.

An on-site combined-cycle gas-turbine powerplant will supply electricity to the desalination plant. Excess power will be sold to the grid.

PUB chief executive Chew Men Leong said, "Desalinated water is an important part of our water supply, and it is set to play a bigger role with the opening of the Tuaspring Desalination Plant. This public-private partnership also illustrates how we have created opportunities for local companies to co-create solutions to meet our water challenges."