Heavy rain floods Nan, damages weir and collapses bridge on key route

Nan province experienced heavy rain on 19 August 2026, leading to flooding and causing damage to infrastructure. An irrigation weir suffered damage, with one side of the Na Lao irrigation weir being washed away by strong currents, which in turn damaged the road beside it. A bridge on Highway 1256, connecting Pua and Bo Kluea, also collapsed, making the route impassable.

Authorities urged residents in at-risk areas to prepare for potential evacuation, as waterways overflowed, flooding homes, farmland, and some roads. Ban Pang Chang in Pong subdistrict was one of the affected areas. The Phayaeng–Kiew Muang road, a key route into Nan's provincial capital, became impassable due to the heavy rain. Authorities deployed a motorboat to assist stranded residents near Ban Sri Bun Rueang in Pong subdistrict.

Strong currents made the rescue operation challenging. Floodwaters also stranded individuals on a bridge over the Muap stream in Du Phong subdistrict, but everyone was eventually rescued. Other districts, including Pua, Chiang Klang, and Tha Wang Pha, reported flooding, particularly near the Nam Pua and Nam Khuang waterways. The Nan municipality reported more than 200mm of rain in several areas since midnight, causing flash flooding in northern parts of the province.

Officials advised residents in at-risk communities to move belongings and vehicles to higher ground and prepare for evacuation, especially those in areas flooded during previous years. In case of remaining at home, residents were advised to stock up on essential supplies and prepare for electricity supply interruptions. The Department of Disaster Prevention and Mitigation urged authorities to move vulnerable residents, including elderly people and bedridden patients, to safer locations if necessary.