CONTEXT:

The Mong Ton Hydropower Project is a massive dam project planned for the Salween (Thanlwin) River mainstem in Myanmar’s Shan state. As originally conceived, the project would create an 870 km² (380 km in length) reservoir capable of storing a vast 37.8 km³ of water. Its reservoir would be the largest in Myanmar by volume and the 26th largest in the world, only slightly smaller than the Three Gorges reservoir on the Yangtze in China. The extent of the reservoir and other technical information related to the dam at its revised 2680 MW design are not yet publicly available.

The Salween River—known as the Nujiang in China and the Thanlwin in Myanmar—is the second-longest river in Southeast Asia after the Mekong, flowing 2,400 km from the Tibetan plateau through Yunnan in China, entering Myanmar in the northeast before flowing into the Gulf of Martaban. The Salween is one of the last remaining free-flowing rivers in Asia, draining a watershed of 283,335 km². Only 17% of the world’s rivers remain free-flowing.

PROJECT IMPACTS:

The Mong Ton dam would be located in a part of the Salween basin that is particularly biodiversity-rich: nearly 85% of the sub-basin is comprised of key biodiversity areas (KBAs), including the Thanlwin southern forest KBA and the Golden Triangle Area, an important habitat for aquatic plant and insect species. The project’s 380 km long storage reservoir would isolate 15 river reach types between the dam and the Myanmar-China border, nine of which are rare or very rare. The Salween mainstem is an important migration route for fish, including species of hilsa, which would be blocked by construction of the Mong Ton dam, together with major changes to fish and aquatic species habitat due to the project reservoir. Changes to flow regime and reduced nutrient content would exert additional pressure on the lower Salween and coastal fisheries.

SOCIAL AND LIVELIHOODS IMPACTS

In Myanmar, the Salween flows through Shan, Karenni, Karen and Mon States. These areas are home to ethnic minority peoples and have been the sites of longstanding conflict between the Burmese government and ethnic armed groups. The Salween basin has a legacy of contested governance and extensive human rights abuses.  The IFC’s SEA Study notes that “Armed conflicts have been directly linked to HPP [Hydropower Power Projects] in this [Salween] basin,” and that  “BAU [business-as-usual] development has high potential to aggravate grievances and conflict, particularly the mainstem HPPs [including Mong Ton] with substantial impacts on natural resources.”

Biodiversity Snapshot

IUCN red list species & status:

CRITICALLY ENDANGERED

White-rumped vulture
Slender billed vulture

Siamese crocodile

ENDANGERED

 Giant Asian Pond Terrapin Bigheaded Turtle

8 endangered fish species

VULNERABLE

Fishing Cat

Asian Small Clawed Otter

4 vulnerable fish species

PROJECT IMPACTS

LESSONS

MONG TON

Myanmar

Dam would obstruct one of the last free-flowing rivers in Southeast Asia, prompting massive biodiversity loss on a river that has received protection from dams within China

Gold panning in the Upper Salween 

Image by International Rivers

Indigenous Karen women protest to keep the Salween River free flowing on the Day of Action for Rivers 2019

Image by International Rivers

Karen organizer speaking out to keep the Salween River free flowing

Image by Wichai Juntavaro

Biodiversity Snapshot

IUCN red list species & status:

CRITICALLY ENDANGERED

White-rumped vulture
Slender billed vulture

Siamese crocodile

ENDANGERED

 Giant Asian Pond Terrapin Bigheaded Turtle

8 endangered fish species

VULNERABLE

Fishing Cat

Asian Small Clawed Otter

4 vulnerable fish species

Company: China Three Gorges

Impact Category

Free-flowing River

Impact Category

Indigenous Peoples

CAPACITY

7110 MW (since revised to 2680 MW)

STATUS

Pre Construction​

1.

It would be inappropriate to develop such a massive project that would block one of the last free-flowing rivers in Southeast Asia, prompting massive biodiversity loss on a river that has received protection from dams within China.

2.

The dam would block fish migration, destroy habitat and inundate critical biodiversity in a richly biodiverse and understudied area.

3.

The dam would have major impacts on local ethnic and indigenous populations, eroding livelihoods and potentially escalating tensions and risk of conflict.