Bangkok Cleans Pipes, Dredges Canals Year-Round to Cut Floods
Bangkok's drainage department and 50 district offices are conducting year-round pipe cleaning and canal dredging across 1,980 canals to improve drainage and reduce flash flood risks. Since 2022 they have cleaned pipes on major and secondary roads, and in 2026 they cleared over 1,400 kilometers of canals.
The Bangkok Metropolitan Administration is pushing ahead with year-round pipe cleaning and canal dredging to enhance drainage efficiency, eliminate garbage and sediment, facilitate water flow, and cut the risk of flash flooding. On November 3, 2026, advisor to the governor Ekwaranyu Amraphan disclosed that the Drainage Department and all 50 district offices are continuously maintaining the city's drainage system through annual pipe cleaning and canal dredging to remove garbage, sediment, and blockages, helping water drain smoothly, reducing flood risk, and improving drainage during heavy downpours.
Bangkok's drainage network comprises 1,980 canals, with maintenance planned according to each area's condition and needs, divided into two main tasks: 1. Pipe cleaning to expand underground drainage capacity. Each year the city cleans drainage pipes to remove accumulated waste and debris, preventing blockages and allowing water to flow easily into canals. Between 2022 and 2026, pipe cleaning was carried out on main and secondary roads. 2. Canal dredging to increase capacity and open waterways. Each year canals are selected for dredging based on necessity, their role in drainage, sediment depth, and canal dimensions. Some locations require frequent dredging, others only when heavy sediment is found, while some are maintained by clearing vegetation and collecting waste to keep water flowing freely. The city continues to manage its canals responsibly.
The goal of opening waterways and canal upkeep is to ensure efficient drainage, keeping the upper reaches of canals free of obstructions such as overgrown vegetation and dumped waste. In 2026, the Drainage Department cleared a total of 1,216 canals covering more than 1,427 kilometers, and also conducted regular canal maintenance including waste collection.
