Plastic waste left along the Mekong River, including near pagodas, boat moorings, makeshift structures, fish farms, riverside vendors and groups gathering to eat and drink, has raised questions about where the rubbish comes from, why there is so much of it and why it seems impossible to clean up completely.
The River Ocean Cleanup organisation raised these concerns following the recent conclusion of the Pchum Ben festival, highlighting the lasting environmental consequences of plastic waste left in the river.
It noted that some Cambodians traditionally float offerings and other objects on the water as prayers for good fortune, prosperity, good health and “blessings for themselves and their families”. These practices reflect religious beliefs, cultural traditions and hopes for a better life.
However, the organisation questioned whether people ever consider what happens to these offerings after they are released into the current.
Some offerings contain plastic bottles, artificial decorations, plastic ribbons and other materials that can remain in rivers for years, it explained. Carried by the current to other locations, these items contribute to plastic pollution, threaten aquatic life, damage ecosystems and pose risks to the health of communities that depend on the Mekong.
River Ocean Cleanup said it was not asking people to abandon their beliefs or traditions, but encouraged small changes to reduce their environmental impact.
People can preserve their faith and customs while choosing offerings made from natural materials, such as banana sheaths and leaves, which decompose naturally. They should also avoid using plastic or throwing waste into the river. An even better option is to make offerings on land at pagodas or other designated locations, it suggested.
“The Mekong River provides us with water, food, livelihoods and life. Protecting the river is also an expression of gratitude and respect for nature,” the organisation said.
“May your prayers bring blessings, not pollution. May your traditions bring good fortune without harming nature. Preserve the blessings, stop the pollution, and work together to protect the Mekong River,” it continued.
It stated that Cambodia can only address waste pollution in its rivers and seas if people collectively committed to ending such practices, supported by the development of waste management infrastructure, public education and consistent law enforcement.
During the 15-day Pchum Ben festival period in 2026, authorities transported 55,648 tonnes of rubbish to tips in Phnom Penh, according to the Ministry of Environment.
The volume was about 10 per cent lower than during the same period in 2025, it added.