Viet Nam - Japan seek coastal erosion solutions

Worsening coastal erosion requires Viet Nam and Japan to enhance sharing of experiences, technology and site-specific cooperation.

Complex developments of coastal erosion

On the morning of September 24 in HCMC, the Ministry of Agriculture and Environment coordinated with the Japanese Ministry of Land, Infrastructure, Transport and Tourism (MLIT) to organize the 14th "Viet Nam - Japan Disaster Management Cooperation Dialogue Workshop". The workshop focused on disaster response technologies related to water, coastal areas, and solutions against coastal erosion. This was also the first time coastal protection and erosion response were included as a discussion topic within this dialogue's framework.

Mr. Nguyen Truong Son, Deputy Director of the Department of Dike Management and Natural Disaster Prevention and Control (under the Ministry of Agriculture and Environment), stated that over 14 years, the dialogue mechanism has become a forum for Viet Nam and Japan to share experiences, knowledge, and technology, as well as exchange practical issues in disaster risk management.

According to Mr. Son, bilateral cooperation is gradually shifting from exchanging policies and management experiences to technical cooperation, introducing, and applying specific technological solutions. The first SABO dam, funded by Japan and built in Son La, is an example, as the structure effectively prevented a mud and rock flood during the floods of July 2026.

Regarding coastal erosion, Mr. Son noted this issue increasingly pressures the management and protection of populations, infrastructure, and socio-economic activities in coastal areas. "Erosion is simultaneously impacted by natural and human factors, so accurately assessing the current situation and causes, and selecting solutions suitable for each area's characteristics are very important", Mr. Son emphasized.

The reality in Viet Nam shows that coastal erosion is becoming increasingly complex. Mr. Dang Van Dang, Deputy Head of the Disaster Safety Control Division (Department of Dike Management and Natural Disaster Prevention and Control), stated that from 2021 to present, the country has seen 312 erosion spots with a total length of about 718 km.

Of these, 178 spots totaling 407 km pose a direct danger to dikes, residential areas, and critical infrastructure, causing land and mangrove loss. To date, 161 spots totaling 313 km have been treated; 134 spots, totaling 311 km, still require continuous monitoring. Some areas experience an erosion rate of over 80 m/year.

Notably, the decline in sediment supply is a key cause. In the Red River system, the average sediment load at Son Tay dropped from about 116 million tons/year in 1957-1987 to 45 million tons/year in 1988-2018. In the Mekong Delta, the sediment volume reaching the region in 2024 was only about 40 million tons/year, down 50-60% from 1980; by 2040, it is forecast to drop to about 4.5 million tons/year.

Along with sediment decline, sand mining, coastal construction, mangrove degradation, sea-level rise, and storm impacts also increase erosion risks. Meanwhile, Mr. Dang noted that identifying the causes of severe erosion in some areas remains limited, leading to the risk of selecting inappropriate technical solutions.

Japan's experiences

Mr. Yusuke Nishimura, Senior Deputy Director of the Coast Division, Water and Disaster Management Bureau (MLIT), stated that coastal erosion is primarily due to an imbalance of sediment along the coast. Reduced river sediment supply, interrupted sediment transport from construction projects and dredging, and sea-level rise can all exacerbate erosion.

In Japan, the approach to combating erosion has also gradually shifted. While past solutions focused mainly on breakwaters and seawalls to protect the coast directly, ongoing erosion shows the need to protect both beaches and sediment transport. Japan has applied littoral drift control structures, offshore breakwaters, artificial reefs, and other solutions to protect the coast on a broader scale.

A notable experience for Viet Nam is managing sediment across the entire system rather than treating individual erosion spots. According to Mr. Nishimura, it is necessary to monitor sediment loads and topographical changes from rivers to the sea, maintain the continuity of sediment transport processes, and conserve and restore coastal sand beaches.

This means anti-erosion solutions must not only focus on a single coastal section but must also consider the sediment source, transport process, and fluctuations of the entire coastal zone. Comprehensive management integrates periodic shoreline monitoring, sediment-load tracking, and research on topographical changes with structural solutions.

The Japanese side also emphasized translating experience into practice through field surveys. Mr. Taizo Ida, Assistant Vice-Minister of MLIT, noted that in disaster prevention and control, workshop discussions must be tied to practical observations to clearly understand the conditions and issues arising in each area.

According to him, from the insights gained through field surveys, both sides can continue to connect with Viet Nam - Japan cooperation contents in the coming time, especially for issues requiring solutions tailored to each region's conditions.

As planned, on September 25, the Japanese delegation will visit Ca Mau to survey an eroding coastal area and response measures. "In disaster prevention and control, going directly to the site and observing the reality is extremely important", the MLIT Assistant Vice-Minister emphasized.

Ha Duyen - Tran Phi