Water Quality

Keeping Our Water Clean

Singapore is a country with limited water resources, and it is essential for its water quality to be carefully regulated. The National Environment Agency (NEA) regulates water pollution and quality in Singapore's inland water bodies and coastal areas.

To keep Singapore’s water clean, soil pollution must also be controlled, as pollutants in the soil can enter the water system as surface run-off or groundwater. Soil pollution control in Singapore focuses mainly on the proper use of approved pesticides to control termites.

Our sewerage system

Singapore's public sewerage system serves all industrial estates and almost all residences. The Public Utilities Board (PUB) regulates the sewerage system, as well as the treatment and discharge of industrial wastewater into public sewers.

All wastewater must be discharged into the public sewerage system. Industrial wastewater must be treated to specified standards before being discharged into a sewer. Additionally, industries which generate large quantities of acidic effluent are required to install a pH-monitoring and shut-off control system to prevent acidic effluent from being discharged into public sewers.

Industries may apply to PUB for permission to directly discharge trade effluent containing biodegradable pollutants into public sewers, with a tariff payment. The tariff will be determined by how much their biochemical oxygen demand (BOD) and total suspended solids (TSS) loading exceeds allowable standards.

The discharge of wastewater into the watercourse (e.g. open drains, canals and rivers) is regulated under the Environmental Protection and Management Act 1999 (“EPMA”) and the Environmental Protection and Management (Trade Effluent) Regulations (“EPM (Trade Effluent) Regs”). NEA’s Pollution Control 1 Division (PCD1) administers the EPMA and EPM (Trade Effluent) Regs.

If a public sewer is not available, industries may apply to PCD1 for a written permission to discharge trade effluent into the watercourse via the following link. More information on the required standards can be found here.

Inland and coastal waters

The water quality of both inland water bodies and coastal areas is regularly monitored. For inland water bodies, the parameters monitored include pH, dissolved oxygen, biochemical oxygen demand, total suspended solids and ammonia. Coastal water samples are analysed for metals, total organic carbon, and other physical, chemical and bacteriological parameters.

Click below to read more about the NEA’s recreational water quality guidelines and monitoring programme:

Regulation of water quality

NEA regulates the water quality in licensable aquatic facilities and registrable aerosol-generating systems.

 Click below to read more about regulation of water quality in the above-mentioned areas: