On Monday, sudden floods brought on by a tropical storm caused a Korean built dam to collapse in Attapeu province of southern Laos. The dam breach destroyed eight villages with scores dead and missing and more than six thousand displaced.
A saddle dam located on the western periphery of the Korean built 410MW Xe-pian Xe-Namnoy hydropower project breached on Monday. Instead of stopping a river’s flow, a saddle dam is used to reinforce the periphery of reservoir. When a saddle dam breaches, water is flushed into areas where water normally has never gone, so the level of devastation can be significant. This creates a new course for water flow and will not stop until the saddle dam is repaired or the reservoir is drawn down to low levels.
The dam burst flushed water from the reservoir in the Xe-Namnoy watershed into the Xe-pian watershed and flooded villages located 1000 meters below. The reservoir sits high above these villages on the Bolaven plateau which is defined by a 1000 meter escarpment on its western edge. The flooded villages sit at the bottom of the escarpment. So the severe drop in elevation added to the immensity of this flood’s impact. The floods came quickly and into an area which rarely floods.
The flood zone is also very close to Laos’s border with Cambodia. Flood waters rushed from the Xe-pian river into the Sekong river, a major tributary of the Mekong river, near the border and then inundated some remote villages in Stung Treng province in Cambodia. It is very unlikely the Cambodian villages were notified of any incoming floodwater. Since this is a tributary system of the Mekong river, there is no built-in warning system for flood or disaster management between Laos and Cambodia. The Mekong River Commission’s information systems do not kick in because these dams are not located on the mainstream of the Mekong (which define the purview of the Mekong River Commission). Clearly more transboundary cooperation is needed.
Beyond any doubt, this was a man-made disaster. The Korean owned PNPC dam company knew the partially built saddle dam was at risk to intense weather patterns during the monsoon season. The company also should have known an easterly tropical storm Son Tinh was barreling down on Vietnam’s coastline. Weather forecasts predicted the hurricane’s landfall days before this incident. This part of the Mekong basin (southern Laos and Vietnam’s central highlands) receive the most rain during the annual monsoon season. Indeed the Korean dam managers noted that the dam site received three times the normal amount of rain.
However, the dam company could have drawn the reservoir down to prevent the dam breach – typically reservoirs need to be drawn down during the monsoon season in Laos. Weather forecasts would have given dam managers many days of warning to draw down the reservoir. The dam company observed “settlement” or a sinking in the top of the saddle dam about 24 hours prior to the dam break, but chose to observe the issue rather than acting decisively The Korean company did issue a warning to the Lao government a possible dam breach on July 23, but this warning came only hours before the dam breach. It is unlikely that adequate warning was given to villages in time to prepare for the impending disaster. Stocks for the two Korean firms invested in the dam fell at rates of 6% and 10% upon news of the dam disaster.
The Korean-built dam is one of 140 dams slated for construction in the landlocked Laos’s portion of the Mekong Basin. About 1/3 of those dams are already completed and another third are under construction. Most of those dams are built on a project-by-project basis by foreign developers from China, Thailand, Korea, and other countries because the Lao government and private sector lack resources to build dams independently. These companies reap the commercial gains from these dams until the dams are handed back over to the Lao government after a concession period of 20-30 years. The Lao economy will not benefit from the export of electricity until the end of these concession periods, but the Lao government is responsible for providing disaster relief in response to disasters like this one.
The dam building spree is part of Laos’s plan to become the “Battery of Southeast Asia” where Laos can graduate from Least Developed Country status by exporting hydropower to its neighborhood. But it is uncertain whether Laos can graduate from LDC status. In June 2018, Prime Minister Thongloun Sisouleth admitted Laos would not meet its twenty-year target of becoming a middle-income country by 2020. There is much uncertainty around whether Laos can become an effective “Battery of Southeast Asia”.
Numerous peer-reviewed studies, including the recent Mekong River Commission “Council Study” and many from the Stimson Center, have warned Laos to the severe risks its damming plans pose to downstream communities and countries. Sediment trapped by dams threatens the geological integrity and rich agricultural yields of Vietnam’s Mekong delta. Dams also prevent fish migration through the Mekong system, and the annual fish catch in Cambodia contributes significant amounts of protein to diets in Cambodia.
Others are critical of Laos’s lack of planning and readiness for disasters such as what happened on Monday. Capacity for adequate weather forecasting and information dissemination is low in Laos, particularly in its peripheral provinces where most dams lie. Disaster response to Attapeu province will be slow and weak in nature due to the low levels of governance in this part of Laos. The flooded area is more than 40 kilometers from any paved road. The only way in and out is through dirt roads that are difficult for wheeled transport especially during the monsoon season. Stimson’s Brian Eyler and Courtney Weatherby traveled 30 kilometers from Attapeu town to one of the flooded villages a few years ago and the trip took two hours in a four-wheel drive pickup truck.
Stimson is tracking the relief effort related to the dam. The US Embassy in Vientiane is supporting the Lao government and international efforts. China and Thailand appear to be leading the relief effort according to media reporting.
This is one of many shocks to Laos’s plans to become the “Battery of Southeast Asia” to hit the country this year. In March 2018, Thailand suspended the purchase of power from the Pak Beng dam, a major Mekong mainstream dam in Laos yet to be built. Renewable energy generation options such as solar, wind, biogas now offer viable alternatives to Lao hydropower in Thailand and Vietnam, traditionally Laos’s major export markets. And China, with a glut of electricity in its own southwest regions, seeks to sell that power to markets in Southeast Asia – this could make Lao hydropower non-competitive in the near a medium term.
Stimson’s Brian Eyler and Courtney Weatherby are doing much media work with major news outlets to provide context to Laos’s damming plans for the Mekong and analysis implications this disaster will deliver to social, environmental, and economic development in Laos and downstream countries going forward. Contact Stimson Center Southeast Asia program director Brian Eyler with inquiries at firstname.lastname@example.org.