Mekong River

NASA satellite network bolsters Mekong River observations

Data sharing said to be key for current and future ‘water diplomacy’ between Mekong Basin countries

May 23, 2023
NASA satellite network bolsters Mekong River observations
A man fishes along the Tonle Sap River near the waterway’s confluence with the Mekong River in Cambodia. Photo: Anton L. Delgado for Southeast Asia Globe

Unevenly split across a half-dozen country borders, the will for transboundary management of the Mekong River rises and falls like its water levels.

But now, with the help of the U.S. space agency NASA, satellite data is set to play an increasingly prominent role in taking the pulse of the river. The organisation announced in early May a growing initiative with the Mekong River Commission and Asian Disaster Preparedness Center. The partnership will keep the gaze of an existing satellite network on the river basin in hopes of shrinking the “data equity” gap between its upper and lower stretches. 

Data sharing between Mekong countries has long been a flashpoint on the river, which is facing a cascade of compounding pressures. The satellite network will prioritise processing data on the river’s most existential concerns: hydropower development and climate change.

Experts hope real-time information on reservoirs, precipitation and water flow will eventually help riverside communities weather the changing ‘Mighty Mekong’. At the same time, they caution this data might not be easily accessible to local people for at least a few years, leaving many to guess at the extremes of the region’s monsoonal climate.

“There is an urgent need for data transparency to better understand how all these different factors are impacting the Mekong,” said Ming Li Yong, who studies transboundary river management with the East-West Center, a U.S. government research group. “But data transparency is one thing, what you do with that data to then make it useful to the people is another thing entirely.”

Spanning 4,350 kilometres, the Mekong is Southeast Asia’s longest river. The headwaters begin in China, where water rushes from the Tibetan plateau and the river is known as the Lancang. Downstream, the river flows through Myanmar, Thailand, Laos, Cambodia and Vietnam before emptying into the South China Sea.

China operates 11 mainstream hydropower dams on its stretch of the river. While that infrastructure is not yet as robust in the Lower Basin, the desire for development is mirrored with 11 more dams proposed for Laos and Cambodia.

“These dams are operated in different countries, by different companies and there is not a lot of data transparency about how,” Yong said. “This has implications for communities who live along the river, who depend on the seasonal rise and fall of the Mekong, and implications for hydropower operations around the river.”

The construction site for the Luang Prabang Hydropower Project in Laos, which currently operates two dams for hydroelectricity and plans to develop two more. Photo: Anton L. Delgado for Southeast Asia Globe.

The relationship between China and the five downstream nations is “a little bit complicated” Yong said with a diplomatic pause. At the headwaters, China has the advantage in Mekong management, she explained, making it “hard to incentivise or obligate China to share data or listen to downstream concerns.”

China’s Ministry of Water Resources agreed to share year-round rainfall and river level data from two monitoring stations with the river commission in a “landmark agreement” in 2020. But river-watchers have long said more information is a must – both from China and the five lower Mekong nations, where the capacity to collect river data greatly varies.

“[Since] data sharing is also based on reciprocity, in the absence of that there is little incentive for countries to share with one another,” Yong said.

Tasked with navigating this pendulum of politics and the push-and-pull of the river itself is the Mekong River Commission, an advisory inter-governmental organisation with the seemingly thankless task of facilitating cooperative management and sustainable development of the waterway.

Commission CEO Anoulak Kittikhoun continuously emphasises the importance of data transparency. In the first ever ‘State of the Mekong’ address last year, he said data was key to “water diplomacy” and assuring Mekong management was decided by “facts, not feelings,” a sentiment he echoed in this year’s speech, specifically calling for more transparent information sharing on dams and reservoirs.

“The new data from SERVIR will have a positive impact on science-based conversations… It represents a step towards improved and more effective basin management,” wrote the Mekong River Commission Secretariat in an email to Southeast Asia Globe. “Without sufficient information, effective management is challenging. With the inclusion of additional data from diverse sources, we can compare and validate information, thus enhancing the quality of our knowledge.”

The confluence of the Mekong and Tonle Sap rivers in Phnom Penh, Cambodia. The aquamarine colour of the Mekong indicates a decrease in sediment flow down the river, which the Mekong River Commission attributed to multiple pressures on the waterway. Photo: Anton L. Delgado for Southeast Asia Globe.

NASA developed the SERVIR satellite network, which is the entity partnering with the river commission, with the U.S. development agency USAID.

SERVIR uses a network of roughly 30 different satellites to process imagery for governments and regional organisations managing natural resources, explained Amanda Markert, the lead for SERVIR’s regional science coordination team. The initiative has already been active in the Lower Mekong for nearly a decade, developing reservoir assessment tools and tracking air pollution.

Over the next five years, Markert said, SERVIR will expand its scope across Southeast Asia and build data tools specifically for the Mekong.

“The public facing side is a web interface tool, a map that tells you different components of water going [in], water going out, water levels,” Markert said.

Related to hydropower, these Mekong tools will focus on tracking dam reservoir levels to learn how much water is being held back from the rest of the river.

However, the SERVIR team was quick to say the satellites won’t be tilted upstream.

“We are looking into the river that is flowing into the Lower Mekong, but we are not working specifically in China,” Markert said.

The China question also came up elsewhere in the partnership.

“Satellite data does not know boundaries between countries, so technically speaking, yes we can look at the reservoirs in China too,” said Peeranan Towashiraporn, a department director with the Asian Disaster Preparedness Center and chief of party for the SERVIR project. 

Still, he added the initiative will “not look into the other reservoirs outside the region.”

A stormcloud darkens the waters of Cambodia’s Tonle Sap Lake, often called the ‘beating heart of the Mekong’ because of the lake’s ability to reverse the flow of the river during rainy season. Photo: Anton L. Delgado for Southeast Asia Globe.

Along the river, the dangerous duo of unannounced reservoir releases and heavy rainfall make vulnerable riverside communities even more susceptible to flash floods. On the flip side, an unknown amount of water being held back by upstream dams at the same time as low rainfall could also cripple agriculture around the Mekong.

“Rainfall is key … that is real-time information people are craving,” Peeranan said from Bangkok, where the centre is headquartered. “We can use that information to inform governments and regional institutions to take actions to address specific problems that could impact their people.”

As an example, he said that if farmers had months of advance notice about regional weather patterns and mainstream water levels, they could then prepare different crops or techniques to safeguard from flood or drought.

A flood map of Cambodia created by the UN World Food Programme in October 2020 using SERVIR Southeast Asia data. The organisation used the map to support disaster management, following devastating floods that left at least 40 dead and affected more than 175,000 families. Map: courtesy of the Humanitarian Response Forum.

While tools to collect this data are currently being made, Peeranan said it may take up to four years until the data is readily accessible to farming and fishing communities that need it most.

“We have to make sure that this information and data can flow from the satellites to regional institutions to countries and all the way to communities that can utilise this information,” Peeranan said. “We may need to build upon the existing dissemination systems that countries already have from national to sub-national to local.”

Even though this is still a work in progress, he said the project is “bringing equity, in terms of accessibility to data and information, to everyone in this region.”

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