With effect from 1 January 2008, IWK is not responsible for providing scheduled desludging service of septic tanks. Under the Water Services Industry Act 2006, owner of premises with septic tanks is responsible for the maintenance of the septic tank.
The maximum volume of sludge that a septic tank can store is approximately one third of its total volume. Regular desludging or removal of the accumulated sludge in the tank is critical to prevent water pollution. The frequency of desludging is dependent on the capacity and design of the septic tank. Septic tanks design according to Malaysian Standards (MS 1228) need to be desludged regularly at least once every two years.
Customer is required to pay for the desludging service provided by a licensed contractor or IWK.