CHIANG RAI– Residents, NGOs, and academics have come out in full agreement against a state plan to spend nearly 200 million baht on building sediment-trap weirs on the Kok River in Mae Ai.
The project is promoted as a way to catch toxic runoff and heavy metals flowing across the border from mines in Wa and Shan State, Myanmar, which have tainted water across the basin. Communities argue the plan will fail, waste money, and damage the river’s ecosystem.
The Living River Association shared that it has worked with Rom Pho Foundation, Rak Mae Nam Kok Group, and Dr Suebskul Kijjanukorn of Mae Fah Luang University to host a forum on the situation. The team gathered evidence on impacts from gold, manganese, and rare earth mining in Wa and Shan States.
Pollution has reached the Kok River near Ban Tha Ton, Ban Mae Mueang Noi, Ban Mueang Ngam Nuea, Ban Mueang Ngam Tai, and Ban Sop Ngam, Tambon Tha Ton, Mae Ai District, Chiang Mai. The findings will be submitted to state agencies.
Evidence shows people in tourism, farming, and fisheries have all been hit by contamination in the Kok River. Water from the river is no longer safe for daily use. Households now rely on tributaries or mountain tap systems instead, which sometimes run dry.
Many communities also pay up to 200 baht per 1,000 litres for delivered water. The lack of clean water for drinking and household use has become the most urgent issue.
Residents also voiced firm opposition to the planned sediment-trap weirs on the Kok River. They say the fix will not work. Government agencies have signalled a plan to build four weirs in Mae Ai District with a budget of 173 million baht.
Locals propose using that budget to install deep groundwater supply systems for all 19 affected villages, so every household has safe water for daily use. They also ask relevant officials to coordinate with the Royal Forest Department or the Department of National Parks, Wildlife and Plant Conservation, since the proposed drilling sites lie within a national park.
The association added that the Department of Water Resources has scheduled public hearings to review water quality solutions for the Kok and Sai rivers. The hearings will take place on 10 Nov 2568 in Mae Ai, and on 11 Nov 2568 at the Chiang Rai Provincial Administrative Organization conference hall. Communities plan to attend both sessions to state their stance.
They will oppose the sediment-trap plan and press the state to tackle the clean water supply for household use first.
Somkiat Khueanchiangsa, President of the Living River Association, said dams and weirs are usually built for irrigation or electricity. This proposal aims to trap sediment and heavy metal pollutants.
In his view, it will harm the ecosystem by turning the river into a reservoir of toxins that threaten water sources, aquatic plants, fish stocks, and fish habitats and migration routes. He believes the budget would be better spent on diplomacy with the governments of Myanmar and China, as well as with the Wa authorities.
