Using a Decision Support System to forecast floods at 28 locations seven days in advance

In 2011, severe flooding in Thailand caused more than 800 deaths and billions of dollars in economic losses; Authorities knew they had to act now to prepare for flood scenarios in the future.

Challenge

Caught off guard with lack of reliable data

Heavy rains during the 2011 monsoon season triggered severe flooding throughout the country. In Bangkok, flooding along the Chao Phraya River affected vast areas of the Thai capital.

With 900 factories in 28 provinces badly impacted, Thailand’s manufacturing industry took a massive hit. In addition, more than 20,000 km² of farmland was damaged. After the waters receded, more than 800 people were found dead and the country’s economic losses stood at more than USD 45 billion.

Without reliable and current flood data, Thailand was caught off guard. Authorities weren’t able to take preventive measures or make decisions on-the-spot to alleviate the devastating impacts of serious floods.

Fully aware that this will happen again, Thailand knew it had to act swiftly.

Solution

Using a Decision Support System to forecast floods

To better manage flood events, the Hydro and Agro Informatics Institute (HAII) – part of the Thai Ministry of Science and Technology – decided to establish an operational water management Decision Support System (DSS).

Driven by MIKE Powered by DHI’s MIKE OPERATIONS, the DSS is able to provide forecasted levels and discharges at 28 locations up to seven days in advance.

Once a day, four models, each covering separate flood plain areas, run in hindcast mode. This brings all model parameters up-to-date, reflecting current hydrological conditions. The system performs forecast simulations if needed, and imports rainfall levels hourly and meteorological forecasts twice a day.

With an intelligent flood forecasting system based on real-time data, Thai authorities could now ease the damaging impacts of severe flooding before and during the monsoon season.

Results

Better flood preparation, safer people and businesses

The DSS is programmed to extract data according to the simulation period, checking the range, rate of change and missing data. It then submits a daily data quality assurance report. Users can access real-time data, forecast data, water balance analysis and flood management tools from its interface.

Armed with current and reliable flood data before and during the monsoon season, Thai authorities could now better manage their flood planning – especially along the entire 160,000 km² Chao Phraya River Basin – well ahead of time.

• Never-before forecast of flood levels now possible at 28 locations seven days in advance
• Early warnings and alarm bells issued in flood prone areas
• Thailand is now better equipped to plan for and initiate emergency actions