Boats and Mekong River

MRC Secretariat affirms Mekong basin size, length

Vientiane, Lao PDR, 18 Dec 2018

Vientiane, Lao PDR, 18 December 2018 – Today, the Mekong River Commission (MRC) Secretariat has found that the catchment area of the entire Mekong River basin is 810,000 square kilometers (km2) with a total length of 4,763 kilometers. Previously, the MRC documents used 795,000 km2 for the basin size and 4,350 km for the length.

The new figures came out as a result of the MRC Secretariat’s analysis of both the basin size and length, in light of different figures used by the public and in its effort to strive for consistency.

“We are motivated to have a consistent use of the Mekong basin size and length since there are different figures out there about the River,” CEO Pham Tuan Phan said.

Overview of the Mekong River basin

In calculating and measuring the whole Mekong basin size, the MRC Secretariat based its work on the Geographic Information Systems (GIS) database taken from MRC studies particularly the former MRC’s Basin Development Plan Program (BDP), Phase II – the program phase that looks at the assessment of the basin-wide development scenarios on the cumulative impact of the riparian countries’ water resource development plans.

The calculation result showed the Mekong River basin covers the entire area of 809,709 km2 (quotable as 810,000 km2). This consists of 184,895 km2 in the upper Mekong in China and Myanmar, and 624,814 km2 in the lower reaches of Lao PDR, Thailand, Cambodia and Viet Nam with a slight coverage of Myanmar.

When looking at the length of the River, the Secretariat re-generated and computed it, using a remote sensing technology via a high-resolution satellite basemap in the ArcGIS software - a type of GIS for working with maps and geographic information - to explore the source of water.

The analysis found the Mekong River has a total length of 4,763 km. It further showed that the River flows 2,077 km through China and Myanmar. Once flowing out of China’s Yunnan province, the River continues to flow another 2,686 km through Lao PDR, Thailand, Cambodia and Viet Nam, where it empties into the Sea.

The Mekong River basin as seen in the high-resolution satellite (basemap) from ArcGIS online

Both the catchment size and length will be consulted further with the MRC member countries and included in the final State of Basin Report 2018 and upcoming Basin Development Strategy for the next period.