30-07-2025
Irrigation Department prepares flood defences
Another round of monsoon-driven downpours is on the way, and personnel, machinery and emergency equipment must be ready, the Royal Irrigation Department has told its regional units.
Det Lekwichai, the department's deputy director-general, stressed the need for preparedness during a meeting at the Smart Water Operations Centre in Bangkok on Wednesday.
Representatives from several agencies attended, with the discussion focused on analysing weather forecasts and water levels in major reservoirs and rivers.
As of Tuesday, reservoir storage nationwide stands at 48.3 billion cubic metres — 63% of total capacity — with 28.1 billion cubic metres of remaining space.
In the Chao Phraya River basin, the four major dams — Bhumibol, Sirikit, Kwae Noi Bamrung and Pasak Jolasid — hold a combined 15.9 billion cu m (64% of capacity), with room for a further 8.9 billion.
The Meteorological Department says that upper Thailand will experience a brief reduction in rainfall between now and Aug 3, followed by heavier showers due to a weakening southwest monsoon. Rainfall is expected to intensify again shortly afterwards.
The Royal Irrigation Department has designated the Bang Rakam field in Phitsanulok province as a natural flood retention area. It will be fully operational by the middle of next month after the rice harvest, officials said.
Farmers are being urged not to replant crops in the area in order to avoid potential flood damage. The department has also told its 17 branch offices to monitor local conditions, adjust water releases where needed, and ensure infrastructure and emergency response equipment are working.
Deputy Prime Minister Prasert Jantararuangtong, who chairs the National Water Resources Committee, said many regions — particularly the North and Northeast — have been hit badly by flooding from Storm Wipha between July 21 and 28.
Some of the highest recorded rainfall occurred in the Nan and Yom river basins and the Upper Mekong Basin. Authorities have deployed inter-basin water routing, early warning systems and crisis-level policy coordination to accelerate recovery.
Heavy equipment, water pumps and sandbags — both standard and 'big bags' — have been deployed to flood-prone areas. Vulnerable groups have been evacuated to temporary shelters, with full support for food, healthcare and utilities.
Mobile kitchens, rescue boats, drones and jet skis have also been pressed into service as needed. Security and transport support are being provided by police and territorial defence volunteers, with temporary Bailey bridges set up in inundated zones.
As of Tuesday, flooding persisted in Nan, Chiang Rai, Phrae and Sukhothai.
In Nan — the hardest-hit province, with more than 500mm of accumulated rain in Song Khwae district — waters are now receding, entering the recovery phase.
The government has also ordered enhanced coordination in the Lower Chao Phraya basin to prevent flooding in provinces such as Chai Nat, Sing Buri, Ang Thong and Ayutthaya.
Dam operations downstream from the Chao Phraya barrage to the Rama VI and Pasak Jolasid dams are being synchronised to manage the anticipated August–September rainfall.
At the same time, agencies remain on high alert for potential rises in the Mekong, with round-the-clock monitoring in place.
