Cambodia's Funan Techo canal could upset Mekong Delta ecosystem: experts

The delta is already suffering legions of dead crops and families without water due to droughts, hot weather, severe erosion of useable farmland, drying out of seafood resources and a series of unplanned events channeling water away from what is known as Vietnam's fruit, rice and vegetable basket.

It is Vietnam's most important agricultural region, on par with similar growing and cultivation areas in its neighboring countries.

As Vietnam and its importers rely on the delta for sustenance, the situation is already dire. And it looks like a canal upstream will make matters worse, according to scientists.

A schoolboy walks on the bed of a canal, which has run dry, in Tran Van Thoi District of Ca Mau Province in the Mekong Delta, March 2024. Photo by VnExpress/Chuc Ly

On May 19, 2023, the Cambodian Council of Ministers approved the Tonle Bassac navigation and logistics system project to maximize the potential of Cambodia’s waterway transportation by connecting the Mekong River system to the sea after a 26-month study has been completed.

The canal, named Funan Techo, is estimated to cost US$1.7 billion, and would be built by Chinese company CRBC through the build-operate-transfer method.

It is set to flow 180 km, connecting the Phnom Penh River port with the Gulf of Thailand in southwestern Cambodia. It will pass through four provinces including Kandal, Takeo, Kampot, and Kep, with about 1.6 million people living on both sides.

The project is expected to have a width of 100 m upstream and 80 m downstream, with a depth of 5.4 m, allowing cargo ships with a total load of up to 3,000 tons to pass during the dry season and 5,000 tons during the rainy season.

It will comprise three water gates, 11 bridges, and 208 km of roads on both sides.

According to the plan, the canal construction will start at the end of this year and be operational by 2028.

Definite negative impact

Le Anh Tuan, a Senior Lecturer at the College of Environment and Natural Resources and the Research Institute for Climate Change at Can Tho University in Can Tho City – the largest commercial hub and de facto capital of the Mekong Delta – said the formation of the Funan Techo Canal will definitely have a negative impact on the region, and that the extent of the impact depends on the scale and purpose of the construction of the canal.

He highlighted a point of concern when saying that the first section of the canal connects the upstream of the Tien River and Hau River, both of which are major branches of the Mekong River in Vietnam, before continuing to flow towards the Gulf of Thailand. The canal will drastically change water flows in these bodies of water.

Cambodia justifies the project as a way to develop inter-Mekong river transportation, but it is very likely to use a lot of water for agricultural and industrial development, Tuan told VnExpress.

As for the structure of the Mekong River's water, the Tien River accounts for 90%, and the Hau River 10%. Therefore, the water from the Hau River is not enough, leading to the excavation of the Funan Techo Canal connecting with the Tien River, he said.

This will lead to a redistribution of water between the two rivers before flowing into Vietnamese territory.

Le Anh Tuan, a Senior Lecturer at the College of Environment and Natural Resources and the Research Institute for Climate Change at Can Tho University in Can Tho City, speaks at a conference discussing the Funan Techo Canal project on April 23, 2024. Photo by VnExpress/Hoang Nam

Depending on the amount of water flowing into the Hau River when it enters An Giang Province, there will be impacts causing erosion from Chau Doc City to Chau Phu District (at the junction with the Vam Nao River) because this river section is narrow, spanning only a few hundred meters wide.

Consequently, the water-regulating role of the Vam Nao River (connecting the Tien and Hau rivers) will be affected, leading to many other issues.

"When the Funan Techo Canal is operational, the Mekong Delta in Vietnam will experience an increase in the shortage of fresh water for daily life, agriculture, production, aside from deeper and more frequent saltwater intrusion, and the ecosystems will be disrupted," Tuan said.

Attending a conference discussing the Funan Techo Canal project on Tuesday in Can Tho, Tuan said the canal project will flow through a region home to about 1.6 million people, creating a basis for economic development in Cambodia. In the future, the population in this area is expected to increase thanks to urbanization along the canal and the growth of many commercial and logistic facilities.

"Therefore, if we consider the full account, including the water needed for domestic and industrial purposes of this project, the water levels in the Tien and Hau rivers reaching the Mekong Delta might decrease by about 50%. During the dry season, the water shortage in the delta could become more severe," he said, adding that with the decrease, the potential for deeper saltwater intrusion could affect over half of the cultivated area in the Mekong Delta in the dry season and during high tide periods.

Moreover, the planning for the Mekong Delta region and local areas for the period 2021-2030 and with a vision towards 2050 may need to be adjusted because those plans were built without the canal project put into consideration.

Tuan said the government's one-million-hectare high-quality rice program could be impacted due to the characteristics of water scarcity and declining soil health, especially during the winter-spring crop season.

The shortage of fresh water in the Mekong Delta will affect dozens of climate change adaptation projects and poverty alleviation projects that have been and are being implemented. A portion of the population that has escaped poverty may be at risk of falling back into poverty and there could be an increase in migration away from the delta, he said.

Pham Dang Tri, Director of the Research Institute for Climate Change (DRAGON-Mekong Institute), also expressed concerns about the negative environmental impact on the Mekong River water system, especially the downstream flow from Cambodia to Vietnam.

He analyzed that in recent years, the Mekong Delta has faced significant challenges from severe droughts during the dry seasons (typically lasts from late November to early May) in the years with El Nino, especially during 2015-2016 and 2019-2020.

Climate change forecasts also indicate a disruption of the natural monsoon cycle, which means the weather will become increasingly extreme, leading to increased frequency of droughts, floods, saltwater intrusion.

Meanwhile, the Funan Techo Canal will control the water source, changing the hydrological flow, leading to more severe water environment and ecosystem problems. This not only affects Vietnam but also the Cambodian people downstream of this canal.

Specifically, it is detrimental to agriculture such as rice production, aquaculture, industry, and people's lives, he said.

Defense mechanisms

According to the 1995 Mekong Agreement, which was signed by governments of its four member countries – Cambodia, Laos, Thailand and Vietnam – established the Mekong River Commission (MRC) to focus on the sustainable development and management of the Mekong River basin's water and related resources, making sure projects affecting the main stream of the Mekong be "technically reviewed" by the MRC and receive feedback from four member countries.

This is an important international legal basis for Vietnam, requiring Cambodia to seek widespread opinions from countries in the region on this canal project.

But Tri does not expect the "impact" of this agency. Because the MRC is only a coordinating party, helping countries negotiate together for the common interest of the river, but cannot enact specific sanctions.

"The problem of the Mekong river basin has been demonstrated through many incidents. For example, when dams are built on the main stream, the MRC cannot decide because they are just a platform for parties to exchange," he said.

However, this is still an official international mechanism that is internationally recognized.

Therefore, in the current context, he believes that Vietnam needs to raise issues of this canal and through MRC to create pressure for Cambodia to provide more comprehensive and detailed reports.

Simultaneously, Vietnamese authorities need to work closely with domestic and international scientists to assess the impacts and consequences of this canal in the future.

A man joins his neighbors in Go Cong Dong District of the Mekong Delta's An Giang Province to get water from a tanker for daily use as the delta suffers from a severe fresh water shortage and salt intrusion, April 2024. Photo by VnExpress/Hoang Nam

Nguyen Nghia Hung, Deputy Director of the Southern Institute of Water Resources Research (SIWRR), stated that continuous monitoring and updating of meteorological and hydrological changes in the Mekong River basin show that the development of hydropower and agriculture upstream has many impacts downstream.

Specifically, the delta has received lower than normal levels of annual floodwaters, which flows to the Mekong Delta to provide migration routes and breeding sites for many species of fish, distributes sediment that retains nutrients for agriculture, recharges groundwater aquifers, and prevents salt intrusion, not to mention washing away chemical residues left from previous crops.

The flow of the river has become deficient against the natural law, with low flow at the beginning of the dry season and the rainy season, making salt intrusion come early.

"The Mekong Delta has been and is being reshaped by these changes," he said, noting that in this context, Cambodia's commencement of the Funan Techo waterway canal will increase concerns about drought and salt intrusion on the delta.

Limited information

Hung continued to say that the information about the project that Cambodia provided to the MRC in the announcement on Aug. 8 last year is still very limited, and did not enough to fully assess the increasing impact on water, sediment, erosion, and salt intrusion.

He believes that the project needs to give the public more information about: the operation process of the entire transportation route in general and the water gates in particular.

Questions need to be answered such as: who will monitor the flow through the canal route compared to the announced average of 3.6m3/s, and how will they do it and be held accountable. Other purposes of the canal route (such as serving agricultural production) include the connection of the canal route with the existing cross-cutting rivers, solutions to minimize the adverse impact with waterway traffic accidents such as oil spills, hazardous pollutants.

But experts have expressed skepticism about some of these motives, and wonder if the company building the canal really cares about anything here other than profit.

According to Cambodia's report, the Funan Techo Canal has three flow control gates, and the average flow through the transportation route is about 3.6 m3/s.

However, Hung's institute SIWRR's preliminary assessment of this canal route yields different results. Specifically, in the case of continuous opening of the gates and increasing some irrigation areas where the transportation route passes, the maximum capacity (Qmax) could be much larger than the data announced by Cambodia.

From this reality, SIWRR recommends Cambodia share more information about the project with MRC and Vietnam, supporting related parties to conduct a more comprehensive assessment of the project. If the impact level is greater than the initial report, MRC and Vietnam need to conduct a joint study on the cross-border impact of the project in all areas, thereby proposing measures to minimize the impact.

Already desperate

The Mekong Delta spans about 40,000 km2 and is home to more than 17.4 million people.

It accounts for 50% of rice production, 65% of aquaculture, and contributes 17% of the country's economic growth.

For a month now, during the peak of the dry season, this region has been experiencing severe saltwater intrusion and water shortage.

According to a 2007 report by the Intergovernmental Panel on Climate Change, the Mekong Delta is one of three deltas classified to have extreme vulnerability of impact from sea level rise caused by climate change, with the other two being the Ganges River Delta of the Brahmaputra River in Bangladesh and Nile River Delta in Egypt.

Regarding this project from a transportation perspective, Khuc Thi Nguyet Hao, a representative from the Department of Inland Waterways under the Ministry of Transport, reported that upon investigation, several impractical points related to the canal project were discovered.

She said Cambodia aims to construct the canal to enhance the logistics corridor for waterway transport. Upon completion of the project, goods traveling from Phnom Penh to China, Korea, and Japan via the 180-km-long Funan Techo canal route from Phnom Penh to Kampot would then need to navigate around Cape Ca Mau of Vietnam, totaling about 900 km.

Therefore, compared to traditional waterway transport routes, this route would extend the journey by about 500 km, indicating that the new canal route does not offer benefits in terms of waterway transportation efficiency.

Previously on April 9, the Cambodian president of the Senate Hun Sen denied information saying the canal could create conditions for Chinese military vessels to enter the Mekong River.