Thailand is located between the Gulf of Thailand in the east and Andaman Sea in the west. The country consists of 77 provinces and its total land area is about 513,115 km² with a total coastline of about 7,066 km and about 299,397 km2 of exclusive economic zone. It has 22 river basins and 353 sub-basins (Table 1), and the two principal river systems are the Chao Phraya River and Mekong River (Figure 1). The total area of inland waters is approximately 3,750 km2. In 2021, the country’s population was 69.95 million and the GDP per capita was US$ 7,273.56 and the fisheries GDP was US$ 3,560 million (Thailand, 2019). Thirty six percent of the land area of Thailand (188,962 km²) lies within the Lower Mekong Basin. The major sub-basins are the North Khong River Basin (17,435 km²); the Northeast Khong River Basin (47,162 km²); the Chi River Basin (49,274 km²); the Mun River Basin (70,943 km²); and a small portion of the Tonle Sap Basin, which is located on the eastern fringes of Chanthaburi and Sa Kaeo Provinces (4,148 km²). The Lower Mekong Basin in Thailand contains a variety of water bodies including floodplains, tributaries, canals, swamps, and reservoirs.