SPECIAL REPORT | Two years after the nation was rocked by severe pollution in Sungai Kim Kim, Johor, which endangered residents, concerns are now mounting as similar pressures emerge around Sungai Langat - a source of drinking water in Selangor.

This river and its tributary, Sungai Semenyih, provide about 30 percent of the water supply in southern Klang Valley.

Like Sungai Kim Kim, Sungai Langat is facing immense pressure from increasing population and demands arising from development and industrialisation.

One of the sources of pollution is effluents from factories in the Mahkota Industrial Park, Banting and other nearby industrial areas.

A visit to the river bank there found that factories were using the waterway to discharge wastewater - which they said is treated - while sand mining was also conducted upriver.

To top it off, vast areas along the river banks were being cleared for the construction of