KOTA SAMARAHAN: A number of rivers in West Malaysia are considered “dead”, says Deputy Energy, Green Technology and Water Minister Datuk Dr James Dawos Mamit.
Speaking at a National Transformation (TN50) dialogue session organised by the ministry here today, James revealed that checks showed the affected rivers have low or zero-levels of dissolved oxygen.
Rivers with low-level or no dissolved oxygen, he said, were a threat to fishes and aquatic plants.
“There are many rivers in West Malaysia categorised as 'dead' due pollution, which contributed to the reduction of dissolved oxygen.
“Without dissolved oxygen, fishes cannot live and the same fate awaits plants growing within the affected rivers.
“Unlike the Peninsular, the situation (pollution of rivers) in Sarawak is still under control,” he said, responding to a question by dialogue participant, who had asked on the efforts undertaken by the government to ensure a balanced development without neglecting environmental conservation.
James did not elaborate on the number of rivers identified with low-level of dissolved oxygen and efforts being conducted to restore the situation.
He, however, noted that the Federal government has embarked on many efforts to ensure that pollution is controlled while developing the country. This effort, he said, would be meaningless without the support and commitment from all stakeholders including the people.
According to a Malaysia Environmental Quality Report 2015 issued by the National Resources and Environment Ministry, only seven per cent or 33 rivers from the total 477 rivers nationwide were categorised as polluted.
A total of 168 rivers of 35 per cent of the total rivers in the country were placed in the “slightly” polluted category while 276 rivers registered clean water quality index.
The report stated that Biochemical Oxygen Demand (BOD) from inadequate sewage treatment, Ammoniacal Nitrogen (NH3-N) from animal farming and domestic sewage as well as Suspended Solids (SS) from improper earthworks and land clearing activities were the main contributors to river pollution.
Meanwhile, water quality and modeling specialist, Dr Zaki Zainudin, said the problem involving rivers with low-level of dissolved oxygen could be resolved by identifying the source of the pollution.
“Like any forms of life, there are fishes and other aquatic life that are very sensitive to the level of dissolved oxygen in the river.
“And the level of dissolved oxygen in our rivers will depend on the quality of the water. If the rivers are severely polluted, hence it would also affect the level of dissolved oxygen in the country,” he said.
Reducing pollution, he said, is less costly compared to cleaning up rivers. He cited the example of the River of Life project, which cost the Federal government more than RM4 billion, to beautify the Klang and Gombak rivers.
“Imagine having to spend the same amount to restore all polluted rivers in the country. Hence, it is better to identify the source of pollution and find ways to reduce it,” he said.