PhD research highlights traditional nature-based solution to combat sea level rise in climate-vulnerable delta

The Ganges-Brahmaputra-Meghna delta, one of the world’s most climate-vulnerable regions, faces growing threats from sea level rise. In his PhD research, Md Feroz Islam explored how Tidal River Management, an traditional water and sediment management technique from southwestern Bangladesh, may offer a sustainable solution.

A nature-based solution

Tidal River Management involves a strategic breaching of dikes to allow sediment-laden tidal waters to flow into low-lying areas, known locally as beels. As the water settles, it deposits sediment, raising the land level naturally. Using advanced 2-dimensional morphodynamic modeling, Islam demonstrated that this nature-based sedimentation enhancing strategy, even when applied seasonally, can raise land levels fast enough to counteract projected sea level rise. 

Most effective in tide-dominated regions

The study found that Tidal River Management is most effective in tide-dominated regions, with coastal beels showing the greatest potential for sediment deposition due to higher tidal ranges. Seasonal operation during monsoons, when river salinity is low, further enhances the approach by allowing agricultural use of the land during the dry season. When applied to multiple beels along the same river, the approach could efficiently raise land levels across large areas of the GBM delta, making it a scalable solution for deltas worldwide.

“Our research also highlights the importance of collaborative governance and stakeholder engagement to ensure long-term success,” says Islam.

Potential strategy for deltas around the world

Feroz Islam’s research underscores Tidal River Management as a promising, nature-based strategy for addressing sea level rise. "Tidal River Management leverages nature's own processes to combat sea level rise," says Islam. "By combining traditional knowledge with advanced modeling, we can create sustainable solutions that not only protect vulnerable deltas like the Ganges-Brahmaputra-Meghna but also inspire resilience strategies for deltas worldwide."

A PhD researcher at Utrecht University’s Copernicus Institute of Sustainable Development, Islam will defend his PhD thesis on 2 December 2024 at the Utrecht Academy Hall.