State of water environmental issues
Around 80% of the country’s area lies within the Mekong River Basin. The remaining 20% drains through Viet Nam directly to the South China Sea. The major tributaries of the Mekong River all have significant watersheds. Besides the major tributaries of the Mekong River, there are hundreds of small streams which mostly have a torrential regime during the rainy season and have a very low or no flow during the dry season.
The total annual flow of water flow in Lao PDR is estimated at 270,000 million cubic meters, equivalent to 35% of the average annual flow of the whole Mekong Basin. The monthly distribution of the flow of the rivers in Lao PDR closely follows the pattern of rainfall: about 80% during the rainy season (May-October) and 20% in the dry season, from November to April. For some rivers in the central and southern parts of the country (particularly Se Bang Fai, Se Bang Hieng and Se Done) the flow in the dry season is less: around 10 to 15% of the annual flow. The rivers outside the Mekong Basin flow through Viet Nam into the South China Sea. These rivers are Nam Ma, Nam Sam, and Nam Neune. The limited information on these rivers restricts assessment of their potential. The estimated inland water resources are approximately 723,500 ha., of which 200,000 ha are from the Mekong River; 54,000 ha from other main rivers; 57,000 ha from reservoirs, 1,500 ha from swamps; 406,000 ha from rice field; and 5,000 ha from fish ponds.
At the beginning of 2001, 140 gauging stations were in operation in Lao PDR. Nearly all of these are in the Mekong River Basin. This is an average density of about 1350 km² per station, the highest among the countries of the Lower Mekong River Basin. Records of flow for the Mekong commenced in 1904. However, the records for the Mekong tributaries are much shorter and vary considerably in length and most tributary stations are located on the lower reaches of the rivers where access is not too difficult.
Water Resources Potentials and Challenges - the abundant water sources in Lao PDR have the potential to support socio-economic development, especially hydropower and irrigation sub-sectors. The hydropower potential of Lao PDR is high compared to other countries in the Lower Mekong River Basin providing an opportunity to earn foreign income. The hydropower sector also has the ability to develop rapidly: it has increased its production about 5 times from 247 million kilowatt hours in 1976 to 1187 million kilowatt hours in 1999 when it exported 473 million kilowatt hours. The government has given high priority to investment in the irrigation sub-sector since agriculture is the foundation of national economic development, necessary for food stabilization and about 85% of the population lives in rural areas. Since 1976 to 2000 the area of irrigated dry season rice increased about 40 times: 2700ha to 110,000ha. The irrigation sub-sector also significantly increased the average yield of rain-fed paddy rice from 1.43 t/ha in 1976 to 3.27 t/ha in 2000. However, the water source development is still at a low level: irrigated area is only 20% of the national paddy area and hydropower production is still at 2% of its potential of 30,000 Megawatts. Development in other sectors is still at a low level compared to hydropower and irrigation. In addition, there are several problems faced by the water sector. These include: unusual rainfall patterns in some years, high evaporation, flood and drought in some of the main agricultural areas of the country; the impact of shifting cultivation on water resources (although this activity has been significantly reduced); and conflict of interests for management within the sector since most water sub-sectors are still responsible for multiple roles of regulator, manager and service provider.
Being a least-developed country with rich water resources, the most important challenges for the Water Resource Coordination Committee (WRCC) in carrying out its coordinating role include: (1) to strengthen the legal framework for an effective and harmonious integration of water resources management, development and protection activities into the socio-economic development process of the country, in particular to meet national priorities; (2) to enhance and consolidate the existing systems and foundation to operate, maintain and rehabilitate facilities safely, reliably and efficiently to protect the investment for public benefits; and (3) to prioritize the capacity-building needs so as to enhance organizational capacity and effectiveness of the water resources coordination system.