Bangladesh is home to one of the biggest and most densely populated deltas of the world, formed by sediments carried by the Ganges, Brahmaputra and Meghna River system. The construction of polders in the 1960s in order to decrease flood risk and salinity intrusion, resulted in high agricultural productivity on the coastal lands for 10-15 years. However since the 1980s, the polders have become a source of major environmental concern due to salinisation, land subsidence, and water logging problems caused by sedimentation in the channel beds. Within this context, the Living Polders research project aims to develop sustainable solutions to these increasing pressures through integrated polder management, based on building with nature principles, working with rather than against the forces of nature (e.g. temporarily opening up polders to benefit from natural sediment accretion to elevate polder surfaces, and deposit fertile nutrients), and taking into account the natural and social dynamics in the area.
Utrecht University has ample experience with studying building with nature techniques based on sediment management (see for example the blog contributions by Floris Keizer on suspended sediment, by Rémon Saaltink on the Marker Wadden project, and the work by Hans Middelkoop and others on the River Care project as well as Jasper Griffioen’s involvement in the Sand Motor project).
As part of the final step for the development of the Living Polders research proposal under the NWO Programme "Urbanizing Deltas of the World", our team of researchers travelled to Bangladesh: Dr Frank van Laerhoven, Dr Jasper Griffioen, Dr Michiel van der Meulen, and Ariane Laporte-Bisquit. The objective of this trip was to consult with various local stakeholders and have a better understanding of the reality on the ground. The next paragraphs describe some of the key highlights of this succesful trip.