Two international organisations have expressed concerns over water quality in the Sesan, Srepok and Sekong rivers which threatens the livelihood of about 3.4 million people in Cambodia, Laos and Vietnam because of human activity and hydropower dam development.
The International Union for the Conservation of Nature and Conservation International, in collaboration with the Cambodia National Mekong Committee, yesterday disseminated a report on the Freshwater Health Index, a new tool to assess freshwater ecosystem health in the Sesan, Srepok and Sekong rivers, which are major tributaries of the Mekong River.
The research and assessment on freshwater ecosystem health through the FHI device found that the water quality in the three basin systems was fairly good despite dam construction.
The basin’s ecosystem has faced increasing stress while investment in conservation and restoration remains very low, according to the report.
Nicholas Souter, freshwater research manager Asia-Pacific of Conservation International, said the factors polluting water quality in the three rivers included more pollution from human activities, especially in the lower areas.
Water pollution from agriculture included the use of pesticides in farming and construction of new roads that led to erosion, especially in areas where heavy rains and water discharged from various uses.
“In order to ensure the continued health of this vital system, improved governance, and in particular, improved access to information both between agencies and between the countries, will be critical,” Mr Souter said.
The researchers began studying the three rivers in 2016 by using existing data from relevant institutions, especially data from the Mekong River Commission, and satellite and models from New Zealand and the United States for measuring and evaluating the health index of water in the three rivers.
As a result, the three rivers received a score of 66 related to ecosystem power, which showed that the water ecosystem had medium quality while water ecosystem service received 80 points, meaning that the river basin could meet the needs of people who depended on it.
Jake Brunner, IUCN representative, said that population and large-scale industry growth, especially in Vietnam’s central mountainous area, could be a source of poor water quality.
Mr Brunner said that if the water is of poor quality, livelihoods without hygiene and malnutrition would be a concern for the future.
“Talking about the three basins as a whole, the water quality is still good at the present time,” he said.