Vientiane, Lao PDR, 6 January 2021 — The water outflow at Jinghong hydropower station in China’s Yunnan province is dropping due to power grid maintenance during 5–24 January 2021, leading to changes in river water levels along the Mekong River in Thailand, Lao PDR, and Cambodia.

According to a notification from China’s Ministry of Water Resources that the Mekong River Commission Secretariat (MRCS) received on January 5, the “maintenance of transmission lines of the power grid” will result in water outflow reduction at 1,000 cubic meters per second (m³/s) from January 5 to 24.

The amount of water flow will be gradually restored to its normal operation status on January 25, the notification said. However, the Ministry did not specify the river level before the reduction or the volume to be restored on January 25.

Based on the MRC’s observed water level data at Jinghong available until January 4, the outflow level started decreasing from 1,410 m³/s on 31 December 2020 to 768 m³/s on 1 January 2021, representing an almost 50% drop. But the flow rose slightly to 786 m³/s over January 1–4.

Mekong River water level at Jinghong in China’s Yunnan province during November 2020–January 2021.

As a result, water levels along the Mekong River are likely to drop by about 1.20 metres, according to MRC’s observed and forecasting water level data.

In Chiang Saen – the first monitoring station on the Mekong River in Thailand located approximately 300 km away from Jinghong – the water already dropped by about 2 metres during January 2–4. The level is expected to slightly increase up to 0.05 metres during January 5– 11.

The stretches from Vientiane to Paksane of Lao PDR, including Nongkhai of Thailand, will experience a drop of 0.22–0.35 metres in their water levels during January 7–11.

In the Mekong mainstream from Thailand’s Nakhon Phanom, Mukdahan and Khong Chiam to Lao PDR’s Thakhek, Savannakhet and Pakse, the water levels will fall slightly less, varying between 0.03 and 0.15 metres during January 8–11.

In Cambodia, the water levels along the Mekong in Stung Treng, Kratie, Kompong Cham, Phnom Penh, Koh Khel and Neak Luong did not see any apparent decrease yet until January 5. The river level at these locations is expected to not change significantly, only dropping between 0.03 and 0.07 metres during January 9–11.

“Navigation activities on the Mekong River, especially around the areas close to Jinghong, may be affected more than the other places during this period. Some local livelihood activities such as riverweed harvesting and fishing may also be affected,” said Dr Lam Hung Son, Head of the MRC Regional Flood and Drought Management Centre, adding that the Centre will continue to monitor the situation closely.

Under an agreement between China and the MRC, China pledged to notify the MRC and its Member Countries of “any abnormal rise or fall in water level or discharge, and other information on factors that might lead to sudden flood.”


Note to editors: 

The MRC is an intergovernmental organization for regional dialogue and cooperation in the lower Mekong river basin, established in 1995 based on the Mekong Agreement between Cambodia, Lao PDR, Thailand, and Viet Nam. The organization serves as a regional platform for water diplomacy as well as a knowledge hub of water resources management for the sustainable development of the region.