King Bhumibol Adulyadej initiated a project to develop the Pa Sak River valley and lower Chao Phraya valley on 19 February 1989 as part of the Maenam Pa Sak Royal Development Project. On 4 July 1991 Prime Minister Anand Panyarachun set up a study group for the dam project. Princess Maha Chakri Sirindhorn presided over a royal ceremony on 15 June 1998, starting the storing of water in the reservoir.