The mighty Mekong River’s growing plastic problem

Thailand: The gateway to the lower basin

Clumps of trash stream down the Ruak River, a tributary of the Mekong, as a herd of rescued Asian elephants watches their mahouts (keepers) pick up the plastic waste.

“The trash is mixed — plastic bags, bottles, food wrappers — the smell of food can tempt the elephants,” says Poonyawee Srisantear, an elephant camp manager in Chiang Saen. “When they play with the plastic, they sometimes try to eat it, which can harm their health.”

Despite Poonyawee’s cleanup efforts, waste continues to flow down the Ruak, reaching the Mekong River less than a kilometer away from the elephants in the Golden Triangle region encompassing parts of Thailand, Myanmar and Laos.

“It feels like it never ends,” she says.

While at Burapha University, Panate led a field study in the Golden Triangle to better understand the source of this trash.

Over the course of a year, Panate’s team collected 2,650 large waste samples from the sections of the Ruak, Kok and Ing rivers that merge with the Mekong. Their research determined that 91% of the waste was plastic, with labels indicating around 30% originated in Myanmar and nearly 20% in China, underscoring the international nature of the challenge.

Panate says he tries “to be optimistic that we are not yet at the irreversible turning point,” but he fears the region’s addiction to plastic will be hard to break.

“We are the first generation facing this problem on this scale. Our ancestors, even our parents, were never exposed to this level of plastic pollution,” says Panate. “Without an alternative, our countries will always choose to use the cheapest, easiest option. For now, that remains plastic.”

Saksan Chuamuangpan, director of Chiang Saen’s Public Health Department, says that population growth and the subsequent rise in plastic use has dramatically increased the city’s waste production over the past two decades.

By one of Chiang Saen’s border ports across the Mekong from Laos, Saksan watches his team attempt to remove rubbish trapped at the port. Over the course of an hour, they barely make a dent.

“The more people there are, the more the city develops, the more the economy develops, the more the use of plastic increases,” he says. “All the countries that share the Mekong River must share the responsibility.”

While just a glance at the Mekong indicates the scale of the plastics issue, quantitative and consistent data across the entire lower basin remains scarce.

“We need more (and better) data to drive policy change,” says Phan Nam Long, a water quality officer with the Mekong River Commission (MRC), an intergovernmental advisory body. “Without information on the scale of the problem, we cannot create effective solutions.”

Next year, the MRC plans to launch a new video monitoring system to measure the flow of plastic waste in the river through strategically placed cameras.

Chiang Saen, where the Mekong first enters Thailand, is one of three Thai locations where monitoring stations are being established. This basin-wide initiative includes 15 additional stations across Laos, Cambodia and Vietnam, including a site in Can Tho — adding to past attempts to understand the scale of the plastic crisis in the Mekong.

The heightened concerns over the level of plastic leakage into the Mekong and its impact on public health prompted the Thai government to announce plans to ban plastic waste imports starting in 2025.

Like other Southeast Asian countries, Thailand upped its imports of foreign plastic waste in 2017 following China’s decision to cut back on trash imports. On top of a lack of waste management infrastructure for dealing with local trash, Thai environmental activist Niwat Roykaew says these imports likely worsened plastic leakage into the Mekong.

Niwat, founder of the Mekong School, which monitors environmental change and development impacts on the river, says the only way to properly address the issue at scale is with regional collaboration.

“Plastic is clogging the river. Who is affected? All of us,” he says. “Waste affects water quality, fish and all living organisms because the river is life.”

Cambodia: The beating heart of the Mekong

Covered from head to toe, workers dredge piles of plastic by hand, trying to keep the piles of waste from washing into the confluence of the Mekong and Tonle Sap rivers in Phnom Penh.

“Most people don’t know how to dispose of their waste properly. They just throw it everywhere,” says Srey Toch, a garbage picker with River Ocean Cleanup, as a pair of children bathe in the waters near where her team was picking up plastic.

Sovann Nou, the organization’s executive director, attributes the problem to inadequate household and industrial waste management, combined with limited awareness among the public regarding the impact of plastic waste.

As he walks the riverbank, he holds up different debris: plastic tarps, bottles and tires. At one point, he pauses to pick up a dead fish and live turtle amid the waste.

Like many cities in neighboring Thailand, Phnom Penh is struggling to contain its own plastic waste crisis — a growing issue made more complicated by the natural flood pulse from Cambodia’s Tonle Sap lake, known as the “beating heart of the Mekong.”

During Cambodia’s wet season, heavy rains swell the Mekong to the point that it reverses the flow of the Tonle Sap river, pushing plastic in the direction to threaten ecosystems and the livelihoods of local fishers.

The river not only transports plastic downstream, but also pushes it back upstream into Tonle Sap lake — a key part of the largest inland fishery in Southeast Asia and a vital protein source for millions of Cambodians.

Beyond Phnom Penh, plastic pickups are happening almost in unison along the floating villages of Tonle Sap lake.

While collecting trash with student volunteers at Kampong Phluk floating village, Sea Sophal, director of nongovernmental organization Bambooshoot, explains that plastic waste is an existential threat to local livelihoods and the lake’s unique ecosystems.

“It is a very visible issue because the lake is at the bottom of every city and river, so all the waste flows in,” Sea Sophal says. “To really change our culture with trash, we need political support, through policy and regulations.”

Since becoming Cambodia’s environment minister last year, Eang Sophalleth has prioritized cutting back on plastic pollution, launching a national anti-plastics campaign.

“Plastic is our No. 1 enemy,” Eang Sophalleth declared at the Cambodia Climate Change Summit last year, urging half of Cambodia’s roughly 17 million population to commit to reducing plastic use.

The minister expressed hope that other upstream nations will follow Cambodia’s lead in beginning to take steps to tackle plastic pollution.

“If we clean up plastics, downstream communities like Vietnam will be grateful. We’ll all benefit,” he says.

Vietnam: Where the Mekong meets the sea

Slipping along the muddy path between rice fields, Trung Tin, a second-generation rice farmer with more than 20 years of experience in the Mekong Delta, squats down to pull up a used pesticide bottle.

Responsible for a 3-hectare rice field in Can Tho’s Thoi Lai District, Trung Tin explains how he rents a drone to spray his field with a growing number of pesticides each year.

“The climate now is not so easy, compared to the past. The soil doesn’t contain as much nutrition,” he says. “For the same soil, you have to fertilize double.”

“We just try our best to protect the rice farm,” he says. “I do not think further. Even if the rice plants get affected, we have to protect it.”

Farmers often leave piles of fertilizer and pesticide bottles by the corners of their fields, he says, explaining that most farmers are afraid to burn them out of fear of inhaling toxins. Trung Tin admits that when the rains come, many of the bottles are washed into streams and canals that lead back to the delta’s rivers.

“I am scared when I eat fish, but I still eat it,” he says with a small shrug.

When the Mekong River reaches Vietnam, the waterway flows out into a vast network of tributaries and wetlands supporting millions of people through farming and fishing, thus becoming the Mekong Delta.

“Most inland waste reaches the river through canals, especially during annual flooding,” says Nguyen Xuan Hoang from Can Tho University’s College of Environment and Natural Resources. “Most of the plastic isn’t from Vietnam, but as the basin’s lowest point, we suffer the most.”

With the new monitoring systems from the MRC going online next year, Hoang and other experts will at least have more real-time data.

But even with that information in hand and perhaps the Global Plastics Treaty next year, Nguyen Cong Thuan, another researcher at Can Tho University, says a regional Mekong-specific action plan is still needed.

“We’re still trying to understand the full scale of the problem, but the longer that takes and the more we learn about plastics, the more the problem also grows,” he says.

Plastic, wrapped in a hideous embrace with water hyacinth, chokes the canals and drainage ways around Can Tho University, about 150 kilometers from Ho Chi Minh City. While a metal screen by the mouth of the spillway traps plastic bags, a steady trickle makes its way past the meshed gates and into the Mekong.

Back on Son Island, with plastic bottles bobbing by, fisherman Le Trung Tin shakes his head when asked if he would ever consider returning to fishing in the Mekong. He simply says there are “too many dangers now.”

“I had to learn to adapt to the more polluted environment. That’s why I decided to farm fish in ponds instead, so I can control the water condition. Fish farmers are developing a better knowledge of the market, the climate and the health of the river,” says Le Trung Tin. “The river is too dangerous for us now.”