Sripong et al. Flood Management in Chao Phraya River Basin The Chao Phraya Delta: Historical Development, Dynamics and Challenges of Thailand ' Rice Bowl 1 Flood

Abstract: The Chao Phraya Rivers and her tributaries, have played a major role in the nation’s history from the periods of Sukhothai to Ayutthaya and Bangkok at present. Their existence was critical to the growth of the Kingdom of Thailand and fostered the development of major cities, including the capital city. In Ayutthaya Period, Thai people wisely used a long inundation during flood time in the Delta as the natural barriers against her country’s enemy. The floodplains of these rivers also provide some of the most productive farmland and continually contribute to the economic growth of the country. The high level of investment in the infrastructure for flood reduction were constructed to minimize the annual risk. But naturally, in the Chao Phraya Delta, flood has continuously been experienced every year due to hydrometeorological and geographical condition. The flood of 1995 demonstrated that people and their properties in the floodplains of Chao Phraya River basin were at risk. Excessive rainfall and related runoff inundated nearly 15,000 sq.km. of floodplains and caused major damages to agricultural land and communities along the river. The inundation nearly exceeded 16 billion cu.m., dike breachin