Residents evacuate as downpour causes flooding in Mae Sai, Chiang Rai

The flooding has raised concerns about waterborne diseases, particularly arsenic contamination, prompting officials to set up four temporary shelters

Mae Sai District in Chiang Rai Province faces severe flooding on Saturday as continuous heavy rains throughout the night caused the Sai River to overflow, flooding several local communities. Residents were forced to evacuate in the middle of the night as water levels surged unexpectedly.



Officials reported that since around 2:00 AM, the water levels in the Sai River rose to breach the protective embankments, flooding areas including Tham Phajom Village, Sai Lom Joy Market, Noi Muang Dang Market, Muang Dang Community, and Mai Lung Khon Community. The floodwaters spread rapidly, with some areas experiencing water depths of 0.5 to 1 metre. Many homes were submerged, and residents were forced to evacuate valuables in the dark.

Officials said that the flooding, particularly under the First Thai-Myanmar Friendship Bridge, occurred after the water breached the embankment, which had been temporarily reinforced with large sacks. This led to the flooding of several communities along the Sai River, an area that had also been severely affected by floods last year.

As of 6:00 AM, the water levels remained high, with the possibility of further rising due to continued heavy rainfall in Myanmar’s upstream areas. Authorities are closely monitoring the situation.

Initial reports revealed that affected communities include those in Moo 1 of Wing Phang Kham Subdistrict, as well as those in Moo 7 and Moo 10 of Mae Sai Subdistrict.

Since the morning of Saturday, military units have been deployed to reinforce the embankments in Ko Sai Village to reduce flooding in the central Mae Sai area. Local authorities, along with the military and other agencies, are working to clear debris from the bridge and evacuate residents. The First Thai-Myanmar Friendship Bridge has been temporarily closed to facilitate the clearing of debris and improve water flow.

Worayuth Khomboon, the district chief of Mae Sai, noted that the flood response has been particularly challenging, as the river is carrying toxic substances mixed with the water. Authorities have warned residents and emergency workers to be cautious. As of 6:38 AM, water levels have begun to recede, but authorities remain on high alert for a second wave of flooding expected around 8:00 AM. Military personnel are working to seal breaches and clear debris from the water’s path.

Wannasilp Jirakas, the acting mayor of Mae Sai, visited the affected areas, which include Sai Lom Joy Market, Mai Lung Khon Village, Ko Sai Village, and Pha Mak Khwai Muang Dang Village. He instructed authorities to alert residents and evacuate from flood-prone areas, as a second wave of floodwater is expected. While this year’s water volume may not reach the levels of 2024, it is still considerably high, he added.

The flooding has raised concerns about waterborne diseases, particularly arsenic contamination, prompting officials to set up four temporary shelters at the Mae Sai Municipality, Wat Phromwihan, Municipal School 1, and Mae Sai District Hall.

Local residents have been using sandbags and plastic tarps as makeshift flood barriers, though the water remains murky with a red tint and mud from Myanmar’s mining areas. Residents are concerned that flooding issues are not being addressed quickly enough, particularly the lack of action on dredging drainage systems. The mud and debris from mines in Myanmar continue to contribute to the problem, and residents fear this will persist even after the waters subside.

(2025/05/24-00:00)