The Singapore National Environment Agency (NEA), regulates water pollution and quality in Singapore's sewerage system, as well as inland water bodies and coastal areas. The control of soil pollution is also an important aspect in this regard, given that pollutants in the soil are likely to make their way into the water system as run-off or groundwater. Soil pollution control in Singapore primarily focuses on the use of approved pesticides to combat termites in soil. Further details can be found here.
Currently, the public sewerage system serves all industrial estates and almost all residential premises in Singapore. All wastewater is required to be discharged into the public sewerage system. The provision, operation and maintenance of Singapore's sewerage system are governed by the Sewerage and Drainage Act (SDA). The treatment and discharge of industrial waste water into public sewers are regulated by the SDA and the Sewerage and Drainage (Trade Effluent) Regulations. The sewerage Act and Regulations are administered by PUB.
The discharge of waste water into open drains, canals and rivers is regulated by the Environmental Protection and Management Act (EPMA) and the Environmental Protection and Management (Trade Effluent) Regulations. The EPMA and its Regulations are administered by PCD.
Industrial wastewater must be treated to specified standards before being discharged into a sewer or watercourse (if the public sewer is not available). Additionally, industries generating large quantities of acidic effluent are required to install a pH monitoring and shut-off control system to prevent the discharge of acidic effluent into the public sewer.
Industries may apply to PUB for permission to discharge their trade effluent containing biodegradable pollutants, as determined by their biochemical oxygen demand (BOD) and total suspended solids (TSS) loading exceeding the allowable standards, directly into the public sewers on payment of a tariff.
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, ammonia and sulphide. Coastal water samples are analysed for metals, total organic carbon, and other physical, chemical and bacteriological parameters.