CHIANG RAI – On August 20, 2025, a roundtable talk was held at Melt in Your Mouth café in Chiang Rai. The event focused on heavy metal pollution in the Kok, Sai, Ruak, and Mekong Rivers.
The discussion brought together over 60 representatives from government, civil society, embassies (including Australia, Japan, the US, and Switzerland), and academics. Ms. Busadee Santipitaks, CEO of the Mekong River Commission Secretariat (MRCS), opened the session.
She highlighted the need for countries along the Mekong to join forces to resolve water quality issues, using science-based solutions to improve river health. She emphasized that while the main concern began with the Kok River, preparations need to cover potential impacts on neighbouring countries as well. The MRC has hosted regular regional meetings to gather input and work with stakeholders.
The first part of the event centred on concerns about water quality in the Kok River. Mr. Surasee Kittimonthon, Secretary-General of the National Water Resources Office, outlined the problems facing the region. Ms. Narumon Nilmanont, speaking for the Chiang Rai Chamber of Commerce, noted that high arsenic levels in the Kok River, traced to Myanmar, have started to hit investor confidence and tourism in Chiang Rai.
Toxic buildup in crops could threaten GAP and GMP standards, risking market losses for local farmers. She pointed out that more direct communication with local communities, using everyday language, is needed so people know how to stay safe and informed.
Efforts to Manage Water Quality
Ms. Kanuengnij Chueamuangphan, a geoinformatics specialist with the Chiang Rai branch of the Provincial Waterworks Authority, shared ongoing efforts to manage water quality since last year’s major flood. She compared the river’s condition to a patient, as turbidity levels have stayed high ever since the flood.
Mr. Pathompong Ritphalang, head of the Chiang Rai Right Bank Weir Water User Group, said local farmers have stopped being able to sell fish and now worry about pollutants affecting rice and vegetables. Many have started digging wells to avoid using river water, fearing for the safety of their harvest.
Dr. Pinida Leelaphanangkham, representing MRCS, explained that in March, when arsenic was found in the Kok River, the MRC promptly sent an official request to Myanmar to conduct joint water testing, including checks in the Mekong River. At that time, it was unclear if the main Mekong had been affected.
Joint tests with the Lao authorities showed excess arsenic in the Mekong from north of the Golden Triangle to Huay Xai (opposite Chiang Khong), averaging 0.025 mg/litre.
“We hope to keep working with Myanmar for regular water checks and to look for solutions to limit the damage. The MRC has started a project to identify pollution sources, monitor water and sediment quality, and help build community awareness on water safety. We want to share data and support collaboration among all groups,” the MRCS representative said.
Pol. Lt. Col. Denwut Jantakhat, President of Ko Chang Subdistrict Administrative Organization in Mae Sai, observed that trade often gets more attention than social problems, even as these issues grow each year.
Cross-Border Water Pollution
He said past government projects mainly focused on trade, like mineral imports, but mining has ended up hurting local communities instead. He questioned whether water issues would be solved in the next five to ten years and raised concerns over safe water for daily use.
Mr. Niwat Roykaew, head of the Rak Chiang Khong Conservation Group, presented a map of the Mekong basin, showing numerous mining sites, including rare earth mines at two places along the Kok River and one along the Sai River. Many more appear along the Mekong tributaries in Laos.
“If we want to address cross-border water pollution, we have to work with MRC and LMC (the Lancang-Mekong Cooperation framework led by China). Nearly every river now has mines. This isn’t a minor regional issue anymore. MRC must make sure all data is thorough and reliable, because negotiations rely on it. I hope MRC links up with LMC, since there’s a regional meeting covering all six countries in December,” said Mr. Niwat.
According to the reporter, the map Mr. Niwat used came from the Stimson Center, a US-based policy research group. They’ve tracked information about the Mekong and used satellite imagery to locate 483 rare earth mines across Southeast Asia, with large numbers in Myanmar, northern Laos, and Vietnam. Over 20 mines were identified at the headwaters of the Loi River in Shan State, which drains into the Mekong.
Illegal Mining in Myanmar
Ms. Pianporn Deetes from International Rivers pointed out the impact of illegal mining in Myanmar, which carries pollution across borders. She called for the MRC to take a stronger lead in coordinating with Myanmar and China to stop upstream pollution. Setting up heavy metal monitoring along the Mekong would help locals access real-time data.
She cautioned that building the Pak Beng Dam would make matters worse and called on MRC to delay construction and electricity generation until proper studies are done, with water quality stations put in place to protect communities.
Dr. Suebskul Kittanugron from Mae Fah Luang University said the risks are complex and cross borders. He welcomed the MRC’s efforts and noted that past solutions tended to rely on construction, which often hurt local villagers. Non-state actors, like armed groups in Myanmar, have also played a role. Civil society in Chiang Rai is trying to work with others to find solutions.
“We need to stop saying the pollution is within acceptable limits. People have a right to know. The only real fix is to shut the mines for good and talk directly with authorities in China, Myanmar, and even the US, who have dealt with mining in Kachin State.
Chiang Rai Hit by Toxic Floods
The government keeps saying it’s too hard, but hasn’t tried. What are we afraid of? We need to do more. Villagers hit by toxic floods need answers. We want our lives back. Chiang Rai needs a centre for heavy metal testing and more open reporting,” Dr. Suebskul said.
Sibella Stern, First Secretary of the Australian Embassy, said the MRC’s cross-border role is key. She encouraged member countries and civil society to make full use of the MRC’s information and facilitation in discussions with Myanmar and China. She also stressed giving affected communities a voice and working closely with social groups.
“In Australia, we face ongoing issues from past gold mining in places like Bendigo. Arsenic remains a problem even 175 years later, so we have to keep treating it. Both Australia and New Zealand use national water quality guidelines, which stress open discussion and equal say for everyone who depends on river water,” Sibella Stern explained.
On the same day, Deputy Prime Minister and Digital Economy Minister Prasert Jantararuangthong, along with Deputy Interior Minister Teerarat Samrejvanich and other officials, visited Naypyidaw, Myanmar. They met with Myanmar’s Natural Resources and Environment Minister, Mr. Khin Maung Yi, to discuss building stronger cooperation on environmental issues, especially sustainable water management.
According to Mr. Prasert, the two countries agreed on the need to work together on environmental protection and water quality management. They plan to hold regular talks and set up a joint technical group to pursue clear outcomes.
He said, “Working together to solve environmental and water issues will help people affected by recent news about water pollution in the Kok and Sai Rivers, which have disrupted daily life in many communities.”
