CHIANG RAI — The Sai River burst its banks early Monday, flooding commercial areas and residential neighborhoods in Mae Sai district as heavy rainfall in Myanmar’s Shan state sent torrents of water downstream. Authorities warned that the worst may be yet to come, with more runoff expected to exacerbate the deluge in coming hours.

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District Chief Officer Warayut Khomboon confirmed the river overflowed at 6 a.m., though a recently constructed flood wall has so far prevented a full-scale breach. However, water has already seeped through, inundating basements and low-lying areas. The river’s flow has been further obstructed by debris—including tree trunks and branches—piling up beneath the First Thai-Myanfriend Friendship Bridge, prompting officials to close the crossing and deploy heavy machinery to clear the blockage.

Residents fear a repeat of last September’s catastrophic flooding, the worst in years for this bustling border town. Mae Sai and its Myanmar counterpart, Tachileik, are no strangers to seasonal floods, but experts warn the disasters are growing more frequent and severe.

CHIANG RAI – The Sai River overflowed early Monday and flooded communities in Mae Sai border district, with evacuation ordered for other flood-prone areas as more heavy rain was expected.

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Underlying Causes Worsen Crisis

Thanapon Piman, a water resource specialist at the Stockholm Environment Institute, cited multiple factors driving the escalating flood risk, including deforestation in Shan state for farmland, unchecked mining, urban sprawl along the Sai River basin, and rising Mekong River levels that slow drainage.

Sukhothai Also Underwater

Meanwhile, further south in Sukhothai province, the Yom River has overwhelmed flood barriers in Si Samrong, Sawankhalok, and Muang districts, swamping homes and businesses. The province—still recovering from last week’s sandbag barrier collapse—now faces another wave of destruction.

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With Mae Sai’s district hospital evacuating patients and debris choking waterways, officials brace for a prolonged emergency. As climate extremes reshape the region’s flood patterns, communities along the Sai and Yom rivers find themselves on the front lines of an escalating crisis.

-Thailand News (TN)