Pa Sak Jolasid Dam

The Pa Sak Jolasid Dam or Pa Sak Cholasit Dam impounds the Pa Sak River at Ban Kaeng Suea Ten, Tambon Nong Bua, Phatthana Nikhom District, Lopburi Province, and Ban Kham Phran, Tambon Kham Phran, Wang Muang District, Saraburi Province, Thailand. It is the biggest reservoir in central Thailand.
The wide and high dam is earth-filled with an impervious core. The storage capacity is 785 million m³ of water at normal water level, with a maximum capacity of 960 million m³. The dam also supplies about 6.7 MW of hydro-electric power.

History

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 permitting 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 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.
On 20 October 1991 King Bhumibol Adulyadej gave the dam its official name, Pa Sak Cholasit. The king also presided over the inauguration of the dam on 25 November 1999. The park is now also a tourist attraction.

Railway and tourism

The construction of the dam meant that the original line of the Northeastern Line Kaeng Khoi-Bua Yai Branch Line would be submerged under the reservoir. Therefore a railway viaduct was constructed in 1998 as a realignment of the line. It opened on 15 June 1998, along with the Pa Sak Jolasid Dam Railway Halt which was constructed to boost tourism in the area.
From November to January each year, the State Railway of Thailand operates a special train service on weekends from Bangkok to Pa Sak Jolasid Dam. The main highlight of the journey is when the train stops on the railway viaduct, allowing passengers to stroll along the track and take photographs.
At the dam area in Saraburi, Ban Tha Rit is a popular viewpoint located at the far end of the dam. This muban has been a community for over 100 years, originally settled along the banks of the Pa Sak River. When the dam was constructed, the riverbanks were submerged, and the surrounding land transformed into vast grasslands instead of rice fields, corn fields, and coconut plantations as in the past.
The area gained new attention as a tourist destination during the COVID-19 pandemic, when people sought open spaces where they could spend time outdoors and maintain social distance. Visitors, especially those from urban areas with limited access to nature, enjoyed activities in the open fields. Meanwhile, local residents who had been affected by the dam adapted by turning to livestock farming, raising goats, sheep, cows, and buffaloes. Feeding these animals has become a favorite activity for tourists, while also providing extra income for the villagers.
Today, the area is a year-round attraction. When the reservoir is full, visitors can admire the dam's scenic beauty, while from February to August the surroundings are ideal for cycling, picnicking, and camping.
Because of its picturesque landscape, tourists have nicknamed the area the "New Zealand of Thailand".