Flash Flooding Hits Chiang Rai's Mae Sai District Following Heavy Rainfall

Residents in Mae Sai's Tambon Mae Sai Municipality were advised to evacuate to higher ground on Monday after the Sai River swelled and overflowed due to 118.8 millimeters of rainfall in just hours. The water level reached 398.31 meters at the Mae Sai Friendship Bridge, prompting officials to warn of increased flooding later in the day. As the situation became critical, residents scrambled to relocate, with some areas experiencing flash flooding and water penetration through flood levees and sewer pipes.

Key Takeaways:

• The Sai River's water level reached 398.31 meters at the Mae Sai Friendship Bridge, leading to overflow and flash flooding.
• The municipality urged residents to evacuate or move belongings to upper floors immediately due to the critical situation.
• Heavy rainfall of 118.8 millimeters in a short period caused the river to swell and overflow.
• The river began overflowing at 4:20am, with officials warning of increased flooding later in the day due to continued heavy rain upstream.
• In some areas, water penetrated through decaying large sandbags previously used to reinforce the flood barriers.
• By late morning, floodwaters had reached Ban Koh Sai village, Ban Mai Lung village, and Ban Pham Kwai Muan Daeng village.

Statistics:

• Rainfall recorded at 118.8 millimeters
• Water level at the Mae Sai Friendship Bridge reached 398.31 meters
• Time of river overflowing: 4:20am
• Time of flooding reaching Ban Koh Sai village, Ban Mai Lung village, and Ban Pham Kwai Muan Daeng village: late morning
• Time of municipality announcing critical situation: 8:21am

Sources:

• Tambon Mae Sai Municipality
• Warayuth Komboon, chief of Mae Sai district