The water supply rate in Cambodia’s provincial cities is low, with Siem Reap, the third largest city, having the lowest rate. The city is unable to meet the water demand of the growing population and tourists visiting the Angkor Wat complex, resulting in severe water shortages and poor sanitation. The Cambodian government has identified improving access to safe water as one of its priority development goals, and has identified the need to expand and improve water supply facilities in eight provincial cities, including Siem Reap, with the aim of providing 90 percent of the urban population with access to safe water by 2023. This cooperation will contribute to improving the living environment in Siem Reap City, which is facing serious water shortages due to rapid urbanization and an increase in the number of tourists, and to promoting the spread of safe and stable water supply services by expanding water supply facilities, thereby improving the living environment and promoting the tourism industry in the area.