Impact of Crop Diversification on Groundwater Sustainability in the Barind Area of Bangladesh: A Case Study on Replacing Boro Rice with Wheat Using Mathematical Modelling

Abstract

Rajshahi is the most water stressed district in draught prone Barind area of Bangladesh. The groundwater level in this area has declining at an alarming rate for the last few years due to over extraction of groundwater, low rainfall, thick clay layer at upper surface with stiff gradient, poor seepage & percolation rate and very limited availability of surface water as well as reducing river water flow of major transboundary rivers etc. Increasing demand of ground water against decreasing trend of groundwater resources has created an alarming situation for sustainable development of this area. For sustainable development of any area, sustainable water resources are a prerequisite. In view of reducing the declining trend of groundwater level as well sustainable groundwater development in this area, this research study was conceived where different options have been investigated using MIKE SHE modeling tool. For sustainability of groundwater resources up to the year 2030, the future condition of groundwater resources from 2017 to 2030 has been predicted. For this reason, ten (10) scenarios were formulated to understand future groundwater conditions in the study area by considering different driving forces such as rainfall, evaporation, groundwater level, surface water level, and water demand. These scenarios have been analyzed to identify the most extreme future scenario that needs to be countered by applying suitable interventions. Scenario 10 (S-10) has been found to be the most extreme scenario where groundwater level in most of the Upazilas (six out of eight) is identified as the lowest level. To counter this extreme scenario, a scenario for the replacement of high-water-consuming Boro Rice with low-water-consuming Wheat has been investigated and found as suitable solution towards sustainable groundwater resources development in Rajshahi district up to 2030.