IWK ensures that wastewater from daily household activities is efficiently treated and managed.
ONCE wastewater disappears, whether from a flushed toilet or a kitchen sink, it is easy to forget about it. Out of sight, out of mind.
Yet wastewater management is a crucial service that safeguards public health, protects the environment and ensures proper sanitation.
In Malaysia, this responsibility rests with the national sewerage company, Indah Water Konsortium Sdn Bhd (IWK).
Despite playing an essential role, sewerage services are often taken for granted until an issue arises.
One of the most common questions households raise concerns the sewerage bill. Issued twice a year, the bill often prompts queries like: What exactly is being paid for? How are the services delivered? Does this mean someone is coming to empty the sewage tank?
Types of sewerage systems
There are two main types: connected sewerage systems and septic tanks (individual or communal).
Properties on connected systems are linked to the public network of sewerage pipelines. Wastewater is channelled through underground pipes to a public sewage treatment plant (STP) managed by IWK.
These properties typically receive a bill once every six months, covering the cost of collection, treatment and infrastructure maintenance.
The above graphic depicts IWK’s main cost breakdowns.
Properties not connected to the central network rely on individual or communal septic tanks.
These tanks must be desludged periodically – ideally once every two years – to prevent overflow and environmental contamination.
IWK provides desludging services upon request. No recurring bill is issued unless the service is carried out, in which case, a one-time fee applies for each desludging.
What the charges cover
For connected systems, the charges support the development, operation and upkeep of Malaysia’s modern sewerage infrastructure.
This includes the operations and maintenance of 9,260 STPs and pumping stations, as well as more than 22,000 km of sewerage pipelines serving a Connected Population Equivalent (cPE) of 33 million.
IWK is also responsible for monitoring environmental compliance, upgrading ageing infrastructure and ensuring uninterrupted operations.
Its STPs operate continuously, 24 hours a day, seven days a week, as wastewater treatment is a constant and demanding process.
Advanced monitoring systems help ensure equipment functions optimally and minimise disruptions.
Although most treatment plants are mechanised and automated, thousands of workers remain essential to manage and maintain the entire system effectively.
While sewerage services operate behind the scenes, their impact is far-reaching, preventing untreated wastewater from contaminating rivers, soil or water supplies, and protecting both the environment and public health.
Why tariffs adjusted
IWK has maintained the same tariff structure for nearly 28 years, since its establishment in 1994.
However, over the years, demand for sewerage services has grown significantly. The company has taken over additional treatment plants, faced rising operational costs and managed increasing wastewater volumes, yet charges remained unchanged until recent revisions.
Sewerage tariffs are set by the Malaysian Government to ensure affordability and fairness while supporting efficient wastewater management.
Tariffs were revised on Oct 1 2022, for desludging services and on Jan 1 2023, for connected sewerage services.
More details are available in the Water Services Industry (Sewerage Services Charges) Regulations 2022 and the amendment 2025 documents below.
The adjusted tariffs help ensure the national sewerage system can continue to meet modern standards, comply with environmental regulations and support population growth.
IWK charges customers below the actual cost of providing sewerage services. The average maintenance cost for premises connected to the central sewerage system is approximately RM17 per month, whereas the current tariff ranges between RM4.09 and RM12.32 per month, depending on the property category.
Customers registered under the eKasih programme have the option to notify IWK to receive support in the form of a rebate. This initiative aims to alleviate the financial burden associated with customers’ sewerage charges.
A closer look at how desludging service charges are allocated.
A similar disparity exists in desludging service, where customers pay RM192 per service despite the actual cost amounting to around RM430 per individual septic tank—based on an average desludging volume of 1.7m³ and a unit cost of RM263 per m³.
The value of sewage services
Sewerage may not be visible in daily life, but its importance cannot be overstated. The charges paid to IWK support a nationwide system that protects health, preserves the environment and ensures safe, clean communities.
Understanding how the system works and what the charges support helps households appreciate the effort behind one of society’s most essential public utilities.
For more information on the Water Services Industry (Sewerage Services Charges) Regulations 2022, click here, and for the (Amendment) 2025 document, click here. For further details, visit IWK’s website or official social media platforms.
