CHIANG RAI– Local groups in Chiang Rai and Chiang Mai are planning a large protest on 5 June to urge the government to act on heavy metal contamination in the Mae Kok and Sai Rivers. They want to bring together at least 10,000 people for the cause.
Pianporn Deetes , campaign director at International Rivers, said the issue first appeared around two months ago. Residents in Tha Ton, Mae Ai District, Chiang Mai, noticed the Mae Kok River was unusually murky.
This led them to call on the authorities to investigate. Water samples taken by the Chiang Mai Office of Environmental and Pollution Control confirmed heavy metal pollution, with lead and arsenic levels above safety standards. Soon after, similar issues were found in the Sai River, which runs through Mae Sai in Chiang Rai.
Community groups filed complaints to Prime Minister Paetongtarn Shinawatra and relevant parliamentary committees. These complaints pushed the committees to visit the area, review the situation, and suggest actions to the government.
The Office of the Prime Minister replied in mid-May that they had passed the issue on to the Ministry of Interior and the Ministry of Natural Resources and Environment for follow-up.
After reading the government’s reply, Pianporn felt officials were treating the problem as just another routine matter, lacking concrete solutions. This led her and her network to plan a major demonstration on World Environment Day.
What Has the Government Done?
In early May, the National Environmental Board formed a subcommittee to address water quality issues. Deputy PM Prasert Chantrarawong heads this subcommittee. Environment Minister Chalermchai Sri-on and Deputy Interior Minister Teerarat Samrejvanich serve as vice-chairs. They’ve brought together 29 agencies to review the situation, look at the causes, and suggest fixes. This includes helping affected communities and discussing with neighbouring countries about pollution sources.
On the local front, Chiang Rai’s Deputy Governor Prasert Jitpleecheep said authorities have been involved from the start. Two committees now oversee the issue—one at the provincial level and another at the policy level, as mentioned above.
The provincial committee focuses on water quality and meets monthly. The next meeting will be on 22 May, led by the governor and joined by local officials, business groups, and academics to review the latest findings.
Despite claims by Pianporn and others that the contamination likely comes from mining activities by a Chinese company in an area controlled by the United Wa State Army (UWSA) in Myanmar, about 20-30 km from the Thai border, the deputy governor said this is only a theory for now. There hasn’t been water testing above the Thai border to confirm the source.
Testing has also been done on crops, aquatic life, and water, including tap water. The results so far show heavy metals below the danger level, meaning the water is safe to use. Prasert explained that even if arsenic is above some standards, it’s still within the limit allowed for bottled drinking water, so he believes it shouldn’t pose a major risk. So far, there is no evidence that heavy metals have entered the food chain.
Recent tests from April by the Chiang Mai environmental office showed arsenic at 0.044-0.049 mg/L and lead at 0.058-0.066 mg/L in the Sai River. The official limit for arsenic is set at 0.01 mg/L by the Pollution Control Department, while the Department of Health allows up to 0.05 mg/L. The limit for lead in both agencies is 0.01 mg/L.
In response to concerns about skin lesions in elephants and abnormal fish, the deputy governor said tests found no link to the heavy metals in the water. He also pointed out that the fish had a disease, which may or may not be related to weakened health from arsenic exposure.
Chiang Rai’s local government continues to monitor water quality and aims to reassure the public that the area is still safe.
Meanwhile, Deputy Governor Siwakorn Buapong from Chiang Mai said the province asked the environmental office to check water and sediment once the problem was known in March, and these checks are ongoing.
Warnings have been sent out to residents along the rivers to be careful with water use, and public health officers have checked up on local health.
He also noted that people in Mae Ai use the Fang River for tap water, not the Mae Kok. To reassure the community, Chiang Mai arranged for extra drinking water supplies.
Meetings have been held to discuss environmental concerns, and the province has asked for help from the Ministry of Higher Education, Science, Research and Innovation to plan long-term improvements for the Mae Kok basin.
The April water quality report showed that while tributaries of the Mae Kok did not have heavy metals above safety limits, some locations still had water quality issues. The province is still waiting for the results of further tests on local crops.
Locals Still Want Basic Rights
Pianporn says any contamination above the legal limit is a problem, no matter how the authorities explain it. Heavy metals can build up in the body over time, affecting health in the long run. The latest results also show arsenic above the limit at points where the Mae Kok meets the Mekong River in Chiang Rai.
She stressed that the people most affected are the poor in the Mae Kok, Sai, and Mekong river areas. These communities rely on local crops and fish for food and have little alternative.
She and her network feel they have to speak out. Reports point to large-scale mining in the region, especially for rare earth minerals, as a looming disaster.
Another concern is that the suspected mines sit in an area under the United Wa State Army, known in Thailand as “Red Wa.” This group runs one of the biggest drug operations in Myanmar, according to the United Nations Office on Drugs and Crime (UNODC). In addition to drug production, Chinese-backed mining is taking place in a lawless area. Neither the Myanmar nor the Thai government appears to have control there.
Earlier, a military spokesperson said that talks with Myanmar’s side revealed that the Wa control the region. The Myanmar government cannot intervene, and the Wa only communicate through the Myanmar authorities, often deflecting responsibility.
Pianporn says all the locals want is safe living conditions, which should be a basic right. But with no clear changes yet, many are left wondering if the government is doing its job.
