BANGKOK: Prime Minister and Interior Minister Anutin Charnvirakul inspected repairs to Khlong R.1, a major drainage canal in Hat Yai, on Monday (Aug 31), ordering agencies to complete urgent work within 90 days to prepare for further flooding.
Anutin was accompanied by Agriculture and Cooperatives Minister Suriya Juangroongruangkit during a visit to the Na Khuan sluice gate on Khlong Phuminat Damri in Khuan Lang subdistrict, Hat Yai district, Songkhla.
Witthaya Kaewmee, director-general of the Royal Irrigation Department, explained that Khlong R.1 was a crucial part of Hat Yai’s drainage system. It receives water from the U-Tapao River basin and channels it towards the sea.
Flooding in 2025 damaged sections of the canal, prompting the department to mobilise machinery, equipment and construction materials for urgent repairs.
Sheet piles to reinforce two-kilometre section
Work includes repairing damaged concrete walls and reinforcing the canal banks with about 5,000 steel sheet piles at vulnerable locations along more than two kilometres.
The reinforcement is intended to prevent erosion and improve the canal’s structural stability. The department aims to complete the work within 90 days.
Officials are also repairing the retaining wall along Khlong Wa and dredging several important waterways, including the R.1 and R.3 drainage canals, Khlong Tha Chang–Bang Klam, Branches 1 and 2 of Khlong U-Tapao, the R.5 drainage canal retention pond and the R.6 drainage canal.
The work is intended to increase drainage capacity throughout the area.
THB400m project forms part of southern recovery plan
Repairs to Khlong R.1 and its associated structures have been allocated a budget of 400 million baht.
The project forms part of a broader programme covering 66 irrigation repair and rehabilitation projects across southern Thailand, with a combined value of more than 821 million baht.
The Royal Irrigation Department has designated the restoration of Khlong R.1 as an urgent priority. The work covers the canal and related structures, improvements to roads running alongside it and the removal of obstructions from waterways.
Medium-term plan to strengthen flood protection
The department’s medium-term plan for 2028–2030 focuses on improving drainage in the main waterways of the U-Tapao River basin.
Key projects include increasing the capacity of the R.3–R.6 drainage canal system, enabling it to cope with a 25-year return-period flood instead of the current five-year level.
Other proposals include improving the 6.8-kilometre Khlong Nam Noi–Khlong Kamnan drainage route, carrying out the second phase of improvements to Khlong Wa, developing the Khlong Tha Chang–Tha Meru drainage system and increasing the capacity of Khlong U-Tapao.
The Khlong U-Tapao proposal remains under study.
New reservoirs and 53km diversion canal planned
From 2031 onwards, the long-term plan will focus on expanding water-storage capacity and developing a more systematic water-diversion network across the U-Tapao basin.
The proposals include several reservoirs and a new 53-kilometre diversion canal extending from Ban Bang Sala in Khlong Hoi Khong district to Bang Klam district.
The planned canal would have a drainage capacity of 1,200 cubic metres per second.
Machine learning to support flood forecasting
The Royal Irrigation Department is also working with Kasetsart University to develop a flood forecasting and warning system for Hat Yai.
The system will combine flood simulations with machine-learning techniques to support real-world water management and disaster preparedness.
It is expected to help agencies assess developing conditions more quickly and select appropriate measures before flooding affects communities.
Witthaya said the department would continue closely monitoring weather and water conditions while accelerating repairs to Khlong R.1, improving drainage capacity and developing the forecasting and warning system.
The measures are intended to reduce the effects of heavy rain and flooding, while strengthening public confidence in Hat Yai and surrounding areas throughout the rainy season.
Anutin instructed the relevant agencies to repair vulnerable locations and restore damaged water infrastructure without delay.
He also called for longer-term improvements to the drainage system, stressing that flood management should extend beyond immediate emergency responses and build a more reliable and resilient water-management system for the future. - The Nation/ANN
