The national water agency, PUB, is calling for an open tender for the second and largest desalination plant to be built at Tuas. To be completed by 2013, the plant will add close to 320,000cum of desalinated water a day to the nation's water supply.

Like the first reverse-osmosis desalination plant at Tuas, the second plant will be constructed under a Design, Build, Own and Operate (DBOO) arrangement and utilise reverse-osmosis technology. The successful bidder will enter into a 25 year water purchase agreement to supply desalinated water to PUB, from the middle of 2013.

The water purchase agreement will set out the tariff structure, terms and conditions for the purchase of desalinated water. The tender for Singapore's second desalination plant will close on 30 September. It's expected to be awarded in the first quarter of next year.