“This year, we witnessed an unusual drop in water levels along the main stream of the Mekong River,” reported Le Cong Thanh, Deputy Minister of Natural Resources and Environment of Vietnam, at the Ministerial Meeting of Lancang-Mekong Water Resources Cooperation in Beijing on December 17, 2019. “Vietnam’s Mekong Delta has been seriously affected by this phenomenon, which will undoubtedly affect our commitment to sustainable development and the lives of millions of people in the region.” Severe droughts of 2016 and 2019 have proven that the long-term, sustainable solution for all six Lancang-Mekong stakeholders including Vietnam is cooperation on data sharing, water resources allocation and efficient and effective utilization of water resources.
Thailand also suffered from drought last year. Since the beginning of the rainy season, tropical cyclones from the southern seas have been less powerful than in previous years and brought little rain to inland areas. The average rainfall in most parts of Thailand was far less than normal as Thailand suffered its worst drought in nearly a decade. On July 24, 2019, Thai Prime Minister Prayut Chan-o-cha made an appeal on behalf of his government, asking the governments of China, Laos and Myanmar to increase the volume of water released downstream to help with drought relief in Thailand.
On July 20, 2019, Cambodia Daily reported that the massive drought in Cambodia dried up the tributaries of Tonle Sap (a lake), causing heavy losses for farmers and fishermen in Khet Battambang. Without fish to catch since April, villagers in the region are facing food shortages and seeking emergency government assistance.
Drought is the most prevalent natural disaster after floods and hurricanes. What caused the drought in the Mekong River Basin? What can be done to prevent and treat the drought? Two experts are shedding some light on the subject.
Driven by global warming, the Mekong River Basin is undergoing tests from rising temperatures and more severe drought. The situation becomes even worse when a strong El Nino occurs and brings high temperatures, or the southwestern monsoon weakens.
Climate change studies show that the frequency and intensity of extreme events such as drought and flood are increasing in most parts of the world, including the Mekong River Basin. If the two extreme events of drought and flood were to occur together or in rapid succession, the results would be devastating to the economy, society and ecological environment.
Both engineering and civil measures are necessary to deal with drought and flood, and effective engineering measures are fundamental. Water storage facilities can store excessive water brought by flooding. When drought hits, stored water helps tremendously. For example, China’s Three Gorges Dam Project has played a tremendous role not only in flood control, disaster relief and shipping along the Yangtze River, but also in terms of energy security. The project has become a successful case of comprehensive water resources management globally. Norway, Switzerland and other developed European countries have also built reservoirs to manage the relationship between power generation, flood control, irrigation and shipping and promoting economic and social development.
To deal with drought and ensure water supply for sustainable socioeconomic development, we should draw on successful international experience and excel in the following aspects:
First, strengthen the water conservancy infrastructure construction in Laos.
We must understand the importance and irreplaceable nature of water conservancy infrastructure construction. The annual water flow in Laos is 334 billion cubic meters (including transit), whereas the monthly distribution of the flow of the rivers closely follows the pattern of rainfall—about 80 percent of the precipitation occurs during the rainy season. However, existing reservoirs in Laos are seriously deficient in runoff storage capacity. Therefore, the country is prone to floods in the rainy season and droughts in the dry season.
The United States built reservoirs on the Columbia and Colorado rivers, each with a storage capacity five to ten times greater than ours. The storage capacity of China’s Yangtze and Han River basins is also about five times greater than ours. These water conservancy projects have played an important role in flood prevention, drought relief and socioeconomic development in the U.S. and China. To handle flooding and droughts effectively, we need more water storage projects urgently and effective utilization of existing reservoirs.
Investing in water conservancy infrastructure is costly. As a developing country, we should create a favorable investment environment to attract more private capital and foreign funds into water conservancy and hydroelectric infrastructure to serve Laos’ socioeconomic development and our people’s wellbeing. Meanwhile, we devise comprehensive water resources plans and allocate space for important infrastructure such as reservoirs. Today, we are carrying out relevant planning with the support of Chinese water resources experts and relevant international organizations. Comprehensive plans for the Nam Ou River and Nam Theun River basins will play an important role in utilization and management of water resources in the basins.
Second, strengthen flood and drought disaster management.
Due to the meager rainfall during the rainy season, current storage in the main reservoirs is obviously less than previous years. The situation has continued to this day, which means that we are likely to face a severe drought in the coming dry season. We need a comprehensive picture of drought-affected areas and a phased water supply plan to meet the needs of daily life. Meanwhile, we should allocate available water resources wisely in drought relief, power generation and environmental protection. We should attach great importance to the security of dams to ensure their normal function for flood control and drought relief. When drought strikes, we must place special focus on disadvantaged groups and provide them with safe drinking water.
The current legal and regulatory system for the management and development of water resources in Laos needs further improvement. An integrated and coordinated institutional mechanism for water resources management should be established between various departments and governments at different levels. An emergency plan for flood control and drought relief should be devised. Relevant rules and regulations should be formulated to support water conservancy projects, manage water usage and enhance water environmental protection to improve the capabilities of Laos to prevent and treat flood and drought.
Third, Laos must strengthen institutional construction and personnel training.
We should draw on the international experience in water resources management and gradually establish a water resources management system fit for the actual situation in Laos. Water resources are basic for longterm socio-economic development across all sectors of society. China has accumulated a wealth of experience in tackling the world’s most complex water problems and has established a practical water resources management system. At present, Laos is communicating with countries around the world including China to build a water resources management system that meets the needs of Laos. High-quality personnel must be an integral part of this advanced system. In recent years, Laos has strengthened its personnel training in water conservancy. Talents trained in China, Japan and European countries have returned to Laos and played important roles. It’s also important to keep the general public informed of major water issues, respond to public concern and seek public understanding and support for water resources management.
Fourth, strengthen international cooperation on water resources management for the entire Mekong River Basin.
Laos is situated in the middle reaches of the Lancang-Mekong River. Water resources management in Laos is an important hub for water resources management throughout the basin that impacts water resources of several countries. We should optimally leverage the Lancang-Mekong Cooperation (LMC) mechanism to strengthen policy dialogue, technology exchange and information sharing while collecting international funds and resources to help Laos improve its water resources management capabilities with mutual respect for the legitimate rights and interests of all countries. We should be fully aware of the challenges and problems facing water resources management and strengthen communication and coordination among countries upstream and downstream, especially relevant cooperation within the LMC framework, to treat floods and droughts in the basin for the benefit of people living there and their sustainable development.
The challenges plaguing water resources in South and Southeast Asia are extremely complex. Population growth and economic development cause demand for reliable water resources to grow accordingly. Periodic monsoons in the region cause large fluctuations between rainfall and runoff, resulting in extreme events of flood and drought. Many big rivers originate in the Himalayas and flow through several countries. All continental countries in the region depend on these trans-boundary rivers, whose main runoff comes from rainfall in the middle reaches. Glacial meltwater accounts for less than 20 percent of runoff of such rivers. The Indus River Basin is an exception with glacier meltwater accounting for approximately 50 percent of its runoff.
A sustained severe drought will occur when a strong El Nino occurs with high temperatures or the southwestern monsoon weakens, like the extreme regional drought in 2016 and the persisting severe drought in 2019. Because the regional drought was caused by greenhouse effects and less rainfall, designing a permanent solution is quite difficult.
Analysis of regional drought shows that over the past half century, the intensity of drought in northeastern Thailand, most of Cambodia and Myanmar has increased, especially in parts of northeastern Thailand. In most parts of the basin, nearly 25 percent of drought happens due to reduced rainfall, especially in northeastern Thailand and Cambodia. Cambodia and Vietnam’s Mekong Delta downstream has been susceptible to extremely severe drought. Analysis of typical drought shows that lower rainfall (compared to the same period) is caused by atmospheric and ocean circulation system anomalies such as El Nino.
Disparities in economic strength and water conservancy project development bring varying drought relief capabilities among Mekong countries. In Cambodia, distribution of irrigation areas is uneven, resulting in different drought relief capabilities in different regions. In Laos, the country’s drought relief capabilities are slightly insufficient due to a limited number of irrigation projects and smaller scale of irrigation areas. In Vietnam and Thailand, relatively high-density, large-scale irrigation projects and networks have been built, which are expected to provide more reliable engineering support for drought relief. Based on my observation and research of drought in the Lancang-Mekong region, I would like to offer the following suggestions:
First, tap the full potential of regional countries to improve capabilities to deal with natural disasters.
Drought relief organizations and networks have been established to respond to drought in Mekong Basin countries. Although the drought relief capability of each country is clearly associated with its level of socioeconomic development, it is also important for countries in the basin to reach consensus on improving drought relief engineering measures. From an engineering perspective, although Thailand and Vietnam have introduced decent drought relief measures, even more engineering measures would still be useful in dealing with severe drought.
Second, strengthen coordination from the perspective of the whole basin to improve the capability of disaster mitigation.
Although reservoirs on the Lancang River mainstream played a key role with emergency release of water to the lower reaches of the Lancang- Mekong River from January to June 2019, 140 percent of natural runoff during the same period, the water levels at hydrological stations at the lower reaches of the Mekong mainstream were still low. This was because runoff of the Lancang River was only 20 percent of the runoff of the whole river during rainy season and 11 percent in dry season. When a drought takes place across the whole basin, greater measures must be taken along the entire river. I suggest that Mekong River tributaries play a more important role in water resource allocation and control. Reservoirs with the storage capacity greater than 20 billion cubic meters have been built in the Mekong River Basin, which should play a positive role in drought relief for each country and the entire basin. I suggest that during in-depth analysis of the impact of drought relief projects on local disaster mitigation, we also study the impact on water disasters in downstream regions or countries to lay a foundation for regional coordination.
Third, optimally utilize the regional cooperation mechanism to improve regional cooperation in the basin.
Water resource is one of five priority areas for the LMC mechanism. Establishment of the Joint Working Group on Lancang-Mekong Water Resources Cooperation by the six LMC countries and the Lancang-Mekong Water Resources Cooperation Center in Beijing marked the birth of the water resources cooperation mechanism among the countries. I suggest we carry out more cooperation within the framework of the LMC mechanism. For example, we need more information sharing and consultation within the Joint Working Group, more joint research on the impact of climate change on the Lancang-Mekong River Basin and how to deal with it, and more joint research on optimal allocation and control of the reservoirs throughout the basin.
Layout by Tian Yuerong