Various methods of sewage treatment systems have been developed over the last fifty years to meet the need to protect public health and the environment. For urban centres where the population is concentrated and the receiving environment is not able to cope with the waste discharge, sophisticated treatment systems have evolved, which produces a high quality effluent. Simpler systems have been used to service small communities although ever increasing environment standards means that even these areas must eventually install better treatment systems.
There are two main types of systems in Malaysia. The most common is the connected sewerage system, while the other is Individual Septic Tanks or Communal Septic Tanks. Other than that, there are more traditional systems such as pour flush and latrines, which are mainly found in rural areas.
As population increases by leaps and bounds, it places more pressure on the environment and impacts the sources of fresh water supplies. There was a growing recognition for proper management of human waste.
From the early 1900s there has been a steady evolution of sewage treatment, leading to the modern sewage treatment plants that are capable of producing high quality effluent, which can be safely discharged to the environment or reused.
More recent developments in sewage treatment have been the improvement of reliability and efficiency of treatment systems to meet the standards stipulated and reduce the land area occupied by treatment works through accelerating natural treatment rates under controlled conditions.
However, despite these developments, sewage treatment systems are still mainly concerned with the removal of suspended and floatable materials, the treatment of biodegradable organic and in some cases the elimination of pathogenic organisms.