Floodplain resource management: An economic analysis of policy issues in Bangladesh

This dissertation investigates the tradeoffs between floodplain agriculture and fisheries production in the Brahmaputra river basin of Bangladesh, where both sectors are simultaneously affected by floodplain development policies. Our goal is to study the impact of development policies on these two sectors and to identify key factors that affect the sensitivity of results. Current floodplain management policies primarily include structural changes in the form of flood control, drainage and irrigation projects, which are designed to enhance agriculture production. These policies ignore the effects on the fisheries sector since it is not a commercially important sector. However, the fishery is an important natural resource sector and a source of subsistence for the rural poor. We develop a floodplain management model (FMM) where net returns to agriculture and fisheries are jointly maximized. The model accounts explicitly for the effect of floodplain area on fisheries production, where productivity is a function of the flood land type. These are derived from simulated annual hydrographs and the area-elevation relationship estimated for the study area. We developed a statistical methodology for simulating hydrographs based on Fourier analysis. The FMM is numerically solved using data from the Bangshi-Dhaleswari floodplain in the North-central region of Bangladesh. Results show that optimal production in a natural floodplain yield higher net returns than where the floodplain is modified by flood control structures. The conditions under which this is true are discussed. This finding has implications for floodplain management policies, which to date have the stated goal of increasing agricultural productivity only. Neglecting the fisheries sector may significantly affect the long-run sustainability of the floodplain. These quantitative findings need to be evaluated in the proper institutional context before policy recommendations are made, since local institutions play an important role in how resources are allocated in the floodplain.