A Singapore Government Agency Website
Official website links end with
Secure websites use HTTPS
Look for a lock () or https:// as an added precaution. Share sensitive information only on official, secure websites.


Singapore is 100 per cent served by modern sanitation today. Used water is collected through a network of sewers that leads to the water reclamation plants. Currently, there are four water reclamation plants serving a population of over 5 million. 

Each year, about 595 million cubic metres (m3) of used water, equivalent to 238,000 Olympic-size swimming pools, is treated to international standards stipulated by the U.S Environmental Protection Agency and World Health Organisation.

Download FAQs for more information on Used Water.

640 x 480

Sources of Used Water

Domestic used water comprises mainly sewage and sullage water. These are generated from households and commercial premises such as hotels, restaurants, shops through activities such as cooking and washing.

Industrial used water is the trade effluent generated by factories from manufacturing process. Trade effluent discharge is controlled through the Trade Effluent Regulations under the Sewerage and Drainage Act. Industries may have to pre-treat the trade effluent to remove any chemical or undesirable pollutants to meet the discharge standards stipulated in the regulations before it is discharged into the public sewer.

640 x 480

Used Water Network

The sewerage network collects used water from domestic and non-domestic (e.g. industrial, commercial, etc) sources.

Used water is channelled through a combination of gravity sewers and pumping stations to the water reclamation plants, where it is treated in accordance to international standards. Part of this treated used water, which is safe enough to be returned to nature, is sent to a separate treatment system in the NEWater Plants. The remaining is sent back to the sea.

As we look to reuse every drop of used water, it is important for everyone to play a part in the maintenance of our sewerage system. Check out the list of tips for a choke-free sanitary system, and a handy guide to maintain sanitary systems at homes and offices.

Connect with Us

For consultations and/or submissions regarding water supply, sewerage and drainage, please email PUB’s Building Plan Unit at