The Pa Sak Cholasit Dam Project is one of the major irrigation projects of Thailand, providing water to the plantations in the Pa Sak valley and lower Chao Phraya valley. The dam also decreases problems of water management in Bangkok by allowing more flood control, as the Pa Sak river was one of the main sources of flooding in the Bangkok metropolitan area.
King Bhumibol Adulyadej initiated a project to develop the Pa Sak River valley and lower Chao Phraya valley on February 19, 1989 as part of the Maenam Pa Sak Royal Development Project. On July 4, 1991 the Prime Minister Anand Panyarachun commanded to set a study group for the dam project. HRH Princess Maha Chakri Sirindhorn presided a royal ceremony on June 15, 1998, starting the storing of water in the reservoir.
On October 20, 1991 King Bhumibol Adulyadej gave the dam its official name, Pa Sak Cholasit. The king also presided the royal grand opening the dam on November 25, 1999. The park is now also a tourist attraction.