Pak Mun Dam is located at the confluence of the Mun and Mekong Rivers in Khong Chiam District, Ubon Ratchathani Province. It is a rock-fill dam with a clay core, measuring 17 meters high and about 300 meters long. The hydroelectric power plant features four turbines with a maximum generating capacity of 136 megawatts, producing an annual average of 280–300 GWh to support the northeastern region's electricity grid.

Construction of the dam began in 1990 and was completed in 1994 with funding from the Thai government and loans from the World Bank. The project aimed to support multiple purposes: electricity generation, irrigation, fisheries enhancement, and flood control.

While the dam has brought benefits in energy and water management, it has also faced heavy criticism for its environmental impact. The Mun River, once a rich freshwater fishery, experienced a sharp decline in migratory fish populations—especially species like the giant catfish and barb—after the dam’s construction.

Although a fish ladder was installed to assist fish migration, the results have been largely ineffective. Local communities have continually advocated for permanent opening of the dam gates during fish spawning seasons. The government has trialed temporary openings, but no permanent policy has been established.

In terms of tourism, Pak Mun Dam has become a key scenic spot in Ubon Ratchathani. A walkway atop the dam offers panoramic views and, during certain seasons, the visible contrast between the Mun and Mekong Rivers creates the striking “two-color river” effect. Visitors can also take boat tours along the Mun River or continue on to nearby attractions such as Pha Taem, Kaeng Tana, and the Two-Color River viewpoint.

The dam grounds include an educational center featuring exhibits on energy production, the Mun River’s history, and environmental information. The area is ideal for ecotourism activities such as nature walks, birdwatching, and sunrise photography—especially during the misty, cool mornings of the winter season.

• From Ubon Ratchathani city, take Chayangkun Road heading toward Khong Chiam District.

• The dam is approximately 75 kilometers from the city and takes about 1.5 hours to reach by car.

• Public buses and vans are available from Ubon Ratchathani Bus Terminal to Khong Chiam.

• Visit in the early morning or late afternoon for cooler temperatures and scenic river views.

• The winter season offers the best conditions for foggy landscapes and sunrise photography.

• If you plan to take a boat trip, negotiate prices with boat owners beforehand.

• Bring sun protection such as a hat or sunscreen, as the dam area is mostly exposed.

• There is ample parking available for private vehicles.

Admission Fee

• No entrance fee (Boat service fees vary and should be arranged with the boat operators.)

Opening Hours

• Open daily from 06:00 AM to 06:00 PM.