Launch of the Mekong Delta’s Sand Budget

In the center of the Mekong Delta, the IKI funded Sustainable Sand Management in the Mekong Delta Project (IKI SMP), managed by WWF-Viet Nam and Viet Nam Dike and Disaster Management Authority (VDDMA), proudly announced the results of the first ever delta-wide Sand Budget for the Mekong Delta on 29 September in Can Tho City. In the midst of escalating sand demand, the study provided the most updated data of sand balance of Tien and Hau Rivers, two main branches of the Mekong in Viet Nam, to the responsible authorities. The study shows that, if the extraction rate remains as usual, in only 10 years, we will use up the mobile sand stock accumulated over hundreds of years by the Mekong River.

Kicked-off in March 2022, the Sand Budget for the Mekong Delta was conducted by experts from Deltares Joint Ventures, including field surveys, secondary data collection, and mathematical modeling to estimate the current sand balance in the delta for the year of 2022, with a vision for 2030-2040. The Sand Budget was built based on four factors: 1) the volume of sand deposited to the delta via two main branches, 2) the volume of sand discharged to the sea, 3) the volume of sand extracted within the delta, and 4) the current mobile sand stock in the riverbed. The measured existing stock of mobile sand in the riverbed varies from 367 to 550 million m3. It is important to understand that this is the sand that was accumulated over many centuries and plays a foundational role for the delta’s stability and climate change resilience. The survey results in 2022 demonstrate that there is only up to 0.6 million m3 of sand discharged to the sea, while the deposited amount to the delta, which is mostly trapped in the upstream dams, dwindles to 2-4 million m3 per year. It is simple math that with the current exploitation rate (35-55 million m3/year), the Mekong Delta existing mobile sand stock may be depleted before 2035. 

With the current development demands, it is impossible to halt sand mining overnight, but the Sand Budget emphases the limited nature of sand, and overexploitation for immediate economic benefits will bring much bigger consequences in the long term.  The Sand Budget also accentuates the sand’s transboundary nature, recommends a centralised delta-wide management system instead of the current provincial management and licensing system and points out the importance of recognising sand as an important resource with appropriate regulations and sanctions.

Moving forward, 16 sustainable alternatives have been identified in Southern Viet Nam to replace river sand in the construction sector. Overall, a Life Cycle Assessment shows positive signs of environmental impacts of using these alternatives. Out of the 16, eight alternatives to sand and gravel sources have been prioritized and recognised, such as construction and demolition waste, M-sand, rice husk and sugar baggage ash. This was the final activity of IKI SMP in the efforts of providing scientific tools like the Sand Budget and alternative solutions for the paradox of sand in the Mekong Delta.