The Sai River, swollen due to heavy rain in the Shan state of Myanmar, has breached its banks in Mae Sai district in Chiang Rai province, causing widespread flooding in the district’s commercial area and several communities.
This morning, district officials warned that flooding will worsen when runoffs from Shan state arrive in the province, raising concerns that the flooding may be as bad as that in September last year, which was described as the worst in many years for this key trading post.
This is the second time that Mae Sai has been struck by flooding this year, with the first in April.
Warayut Khomboon, the district chief officer, said that the swollen Sai River overflowed its banks at 6am today, though it has not yet breached the flood wall, which was built by the army engineering corps earlier this year.
He noted, however, that water has seeped through the flood wall and into the basements of buildings in several communities, adding that the level of the river is steadily rising, but its flow is being blocked by a huge amount of debris, tree trunks and branches under the First Thai-Myanmar Friendship Bridge.
He also said that the bridge will be closed today and a backhoe will attempt to remove debris from the river.
Most patients have been transferred from the district hospital to hospitals elsewhere, he disclosed.
Mae Sai district, and its twin Tachileik township on the Myanmar side of the border, are prone to flooding, which normally occurs 2 or 3 times a year. Last year, though, they were hit by flooding eight times, with the most destructive being recorded last September.
According to Thanapon Piman, a Thai water resource expert at the Stockholm Environment Institute, numerous factors have been identified for the increasing frequency and severity of the flooding. They include:
• Unusually heavy rainfall in Shan state, the source of the Sai River
• Replacement of forest cover in Shan state by farmland
• Massive mining activities
• Urban expansion in Mae Sai and Tachileik
• The disappearance of flood paths
• The rising level of water in the Mekong River, which slows the flow of Sai River
Meanwhile, in Sukhothai province, the Yom River, swollen due to runoffs from the Nan River, has breached the flood wall in Si Samrong, Sawankhalok and Muang districts, submerging many residential and commercial areas.
