NWRO prepares Sirikit Dam discharge and Chao Phraya floodplain storage as heavy rain hits mid-August

The National Water Resources Office (NWRO) convened an emergency meeting on August 14 to prepare for heavy rainfall expected in the coming days.

Forecasts from the Meteorological Department and the Hydro-Informatics Institute (HII) indicate that between August 14 and 18, Thailand will experience continuous rainfall, with heavy to very heavy rain in the upper North, upper Northeast, East, and South. The NWRO has issued a warning for these regions to be on alert for flash floods, landslides, waterlogging, and a potential rise in water levels in the Chao Phraya River from August 15-17.

Chao Phraya Basin Water Management Plan

The meeting reviewed measures to manage water in the greater Chao Phraya Basin in anticipation of the incoming weather:

1. Floodplain Storage:

• Bang Rakam floodplain: Ready to receive water from August 15.
• 10 central region floodplains: Expected to be ready to take in water after September 15.

2. Dam Operations:

• Sirikit Dam: Currently holds 7,911 million cubic metres of water (83% of capacity). It was agreed to maintain the current discharge rate of 55 million cubic metres per day until September 2, to increase storage capacity for incoming flows.
• Lower dams: Plans are in place to expedite water release from the Phajuk, Naresuan, and Chao Phraya dams in coordination with upper dam discharges, ensuring no adverse effects downstream and prioritising dam safety.
• Low-water dams: For example, Lam Takhong Dam, expected to have low water levels by November, will reduce discharge to conserve water for the coming dry season.

The meeting requested that the Meteorological Department and the Hydro-Informatics Institute produce seven-day rainfall forecasts, updated daily, to support timely water management decisions. The goal is to minimise flood impacts while securing maximum water storage for the dry season.