CHIANG RAI – The Provincial Waterworks Authority (PWA) in Chiang Rai recently hosted a press tour, inviting local reporters to visit and see the water treatment process up close.
The goal was to give the public peace of mind by showing how water quality is tested, managed and maintained at every stage. The PWA assured everyone that tap water in Chiang Rai meets international benchmarks for cleanliness and safety, with absolutely no arsenic contamination.
Jakrapong Kumchan, the Provincial Waterworks Authority Governor, explained that the team keeps a close watch on the Kok River — Chiang Rai’s main water source. Concerns had come up after reports of unusual cloudiness and arsenic levels above the recommended limit.
The PWA responded by stepping up monitoring and adjusting treatment methods as needed. Chlorine is used to remove heavy metals, and the clarity of incoming water is checked before it moves through the rest of the process. Every step is tightly controlled, and expert scientists review the water’s quality before it goes out to people’s homes.
To handle situations where raw water contains more heavy metals, the PWA has upgraded its chemical dosing machines.
New systems are being rolled out at Wang Kum Waterworks and other key sites like Mae Sai and Koh Chang, with a total of six new units costing more than 15 million baht. This is meant to improve water quality control even further. These machines are being installed now.
Regular testing happens on several levels. Water samples from the intake, treatment system, storage tanks and households are sent every two weeks to a certified lab for independent analysis. Daily checks are also carried out by PWA staff.
The results are posted on the Chiang Rai and Mae Sai PWA Facebook pages every three days, so everyone stays informed. The latest test results from July 21, 2025, showed that all water supplied by PWA meets safety standards, with no traces of arsenic detected.
During the press tour, journalists had the chance to see firsthand how water is produced at the Wang Kum station and to watch lab staff at work. These efforts are part of an ongoing commitment by the PWA to maintain public confidence that tap water in Chiang Rai is clean, safe and free from arsenic.
Deputy Governor Sutthas Nuchpan reminded residents that the PWA is aware of their concerns and works hard to keep tap water safe for all uses. People are encouraged not to use untreated river water for drinking or household needs.
If anyone has questions or wants more information about water quality or usage, they can contact the Chiang Rai PWA branch at 053-711655, the Mae Sai branch at 053-731010, or the PWA Contact Centre on 1662, which is available around the clock.
