Pa Sak Jolasid Dam

The Pa Sak Jolasid Dam or Pa Sak Cholasit Dam (เขื่อนป่าสักชลสิทธิ์, ) 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 4860 m wide and 36.5 m 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 of the following year annually, for a total of three months, the State Railway of Thailand (SRT) operates a special train known from Bangkok to Pa Sak Jolasid Dam. It operates only on weekends. The main highlight is when the train stops on the railway viaduct, allowing passengers to stroll and take pictures.

In the area of ​​the dam in Saraburi, Ban Tha Rit is a popular viewpoint at the end of the dam, it is a muban (village) that has been settled as a community for over 100 years. At first, the folk settled along the bank of Pa Sak River. The dam was built and so the reservoir, the bank of the river was covered with water. However, the land next to the reservoir became a big grassland instead of rice and corn field with coconuts plantation like it used to be. The area became a tourist attraction because of the COVID-19 pandemic situation. Tourists could not make a trip during that time so when they saw a big open area they discovered that it was a suitable place to spend time outdoor, every group could stay away from others. Tourists like to spend time here especially tourists from the city, they have limited chance to spend time in this environment. For the folks when affected by the dam, they turned to raising livestock such as goats, sheep, cows, and buffaloes. It is like a new career for those farmers. Tourists have pleasure when they feed those animals, providing food for their livestock generates more income. This is all-year-round tourist attraction, when the reservoir is full of water tourists can enjoy the beauty of the dam but activities like cycling, picnicking, or camping could be made during February and August.

ฺBecause of these atmospheres, it received the nickname "New Zealand of  Thailand" by tourists.