Pak Mun Dam
From ON THE RIVER OF NO RETURNS: THAILAND’S PAK MUN DAM AND ITS FISH LADDER, Tyson R. Roberts, ThaiScience 2001 (pdf)
Most fish species living in the Mun River are unable to climb or are for other reasons not using the ladder installed on Pak Mun Dam. This is especially true for large species most important in wild-capture fisheries. The ladder is unsuccessful in maintaining fish spawning migrations because few or no gravid females of any species climb it. Various proponents of Pak Mun Dam claim that its main impact on fish is that they cannot swim upstream and downstream past the dam. This is far from the only impact. The real problem is not with the ladder. Rather Pak Mun Dam itself is ecologically unfriendly to fishes.
A reservoir outflow is not a normal river. The abnormal flow regime and other artificial features in the outflow of Pak Mun Dam have severe impacts on fishes for 4.5 km until it joins the Mekong mainstream which dissipates (but is also effected by) its negative impacts. Pak Mun Reservoir is also very unfriendly to fish. This apparently is due mainly to having its bottom smothered by silt and its open water with an exceptionally heavy silt load at all times because of the highly abnormal “run of the river” flow conditions.
When the water level in Pak Moo Reservoir is at 108 m. “peak electricity generation” causes daily fluctuations in water flow downstream from Pak Mun Dam and daily draw-downs in the reservoir that disturb fish habitats and disrupt fish migration. If reservoir water levels are too low, the amount of water released from the sluice gates may be less than the lowest flow that normally occurs for only a few days or weeks of particularly dry years (if the reservoir level falls below 94 m the outflow will stop altogether). During minimum outflow the water quality also can be much poorer than that of normal dry-season low water without the dam. The other extreme occurs when water has to be released to prevent the reservoir itself from over-flowing. Opening the sluice gates on the spillways when the reservoir level is high can create a destructive torrent far stronger than any that occurred during the worst floods in the Moo River before Pak Moo Dam. Maximum as well as minimum outflows from Pak Moo Reservoir are lethal to fish.
The problem of Pak Mun Dam and fisheries may be summarized as follows: an artificial and hostile downstream environment (reservoir outflow) and an artificial and hostile upstream environment (reservoir) are connected by artificial and hostile corridors (fish ladder and dam spill-ways). The resulting impact accumulation has devastating over-all effects on fish habitats and fish species. Pak Mun Dam together with its 35-km long reservoir and 4.5 km reservoir outflow is a major geographic barrier to all kinds of fish movements between the Mekong and the Mun.
Japan announced a new three-year Mekong aid plan Saturday at the Japan-Mekong Summit to promote stability and growth in the region, and counter China’s growing political and economic clout in Southeast Asia.
“Japan will commit about ¥750 billion in official development assistance over the next three years,” Prime Minister Shinzo Abe said at a news conference attended by the leaders of the five countries that make up the area. “Japan is a partner for the development of the Mekong region, which has future potential.”
The five Mekong nations are Cambodia, Laos, Myanmar, Thailand and Vietnam.
via Japan, Mekong ink new ¥750 billion aid deal | The Japan Times.
Japan, Thailand and Myanmar have signed a memorandum of intent for the joint development of the long-delayed Dawei project in southeastern Myanmar.
The document was signed on the sidelines of the Japan-Mekong Summit in Tokyo.
Thai Prime Minister Prayuth Chan-Ocha said the project will become a new distribution hub for the world.
“The cooperation between the three countries on Dawei will be the world’s new economic gate linking the Pacific and the Indian Ocean. This will be major opportunity for Japan’s private sectors with Thailand’s support as manufacturing base, as a connecting point and as a product distribution centre to the region. With this, we reaffirm that Thailand will do its best to look after Japanese investment’s best interests.”
The project has been stalled for years largely due to the Italian Thai Development (ITD), which had failed to secure private investment and agree on a power source for the complex.
via Japan,Thailand and Myanmar Sign Memorandum of Intent for Dawei Project.
It is the middle of winter in the Mekong region; however, throughout December, floods have brought havoc to communities along the Mekong River. From the Chiang Saen District, Chiang Rai province in Northern Thailand downward, the water level in the Mekong has risen rapidly. The flooding was most intense along the Thailand-Lao border from the Golden Triangle toward Khong Chiam, Ubonratchathani. It is unprecedented to experience such flooding in the Mekong during wintertime.
Flooding was particularly bad in Chiang Saen District around Sob Kok, the delta plain in the Kok River where it meets the Mekong. In just one morning, the flooding damaged a large plantation owned by local villagers. Water from the Mekong River suddenly spilled over the banks causing levels of water tens of centimeters high to flood the area; corn, tobacco, bean and other vegetables vanished in the blink of an eye.
On December 19, The Vientiane Times reported that construction on the Xayaburi Dam was halted as the Mekong River rose, flooding the site. The Xayaburi Power Company – owner of the US$3.5 billion hydropower project – announced that “work on the dam’s spillway had to stop when water flowed over the temporary barriers and lower parts of the area were submerged.”
via Mekong Floods: The Dampening of the Wintery Suffering | International Rivers.
China should join an intergovernmental commission supervising development of the Mekong River to more effectively address environmental and other problems faced by downstream Southeast Asian nations, a senior U.S. government official says.
Aaron Salzberg, special coordinator for water issues at the U.S. State Department, also underlined the importance of political will in ensuring that the Mekong River Commission (MRC) functions as an effective forum in coordinating shared use of the region’s main waterway.
“In the long run, I think it would be good for China to become a full active member in the MRC … sharing data so that the downstream countries actually understand what’s going to happen and when it’s going to happen and they can prepare accordingly for those types of things,” Salzberg told RFA.
“China can play an active role in managing their infrastructure for downstream benefits,” he said.
Five dams commissioned in China on the Mekong river’s upper portion have caused rapid changes in water levels and other adverse effects downstream, especially in the four countries of the Lower Mekong Basin—Vietnam, Cambodia, Thailand, and Laos—where tens of millions of people depend on the river for food, water, and transportation, environmentalists say.
China has refused to join the MRC—which comprises the four lower Mekong nations and manages development along the Mekong—although the river’s source is located within the Asian giant’s borders, saying it prefers to negotiate on a bilateral basis to resolve any problems on the issue.
via China Should Join Mekong Commission: US Official.
Korea has pledged additional support for infrastructure and economic development projects along the Mekong River in Southeast Asia.
Finance ministers from Korea and Laos signed a memorandum of understanding in the Laotian capital of Vientiane on Friday that calls on Korea to deliver around 200 million U.S. dollars in development assistance as part of the Economic Development Cooperation Fund.
The two countries plan to build embankments along the Mekong River for the construction of roads and bridges and seek out new business projects using the Hangang River in Seoul as a model.
via Arirang News :: Korea vows financial support for development along Mekong River.