From Over to Optimal Irrigation in Paddy Production: What Determines Over-irrigation in Bangladesh?

The journal article examines the level of optimal irrigation and the determinants of over-irrigation in paddy production since about three-fourths of freshwater withdrawal in Bangladesh is used to irrigate paddy plants. The Cobb-Douglas production function reveals that optimal irrigation is 75 × 102 m3 per acre per season. Results show that nearly 39% of water is over-irrigated. It escalates farmers’ irrigation costs by USD 56 per acre and induces additional depletion of 60 × 102 million m3 of freshwater with substantial welfare losses (USD 70–73 million) in south-western Bangladesh. Further analyses reveal that farm characteristics, salinity, and irrigational modes determine over-irrigation in the study area. The paper suggests that the alternate wetting and drying (AWD) technique helps farmers reach the optimal level by reducing over-irrigation substantially. Welfare effects of the AWD technique are an 89–93% reduction in over-irrigation and a 68–71% reduction in ancillary costs.

Authors: Islam, Md. Sariful; Tumpa, Shamshunnahar; Afrin, Sonia; Ahsan, Md. Nasif; Haider, Mohammed Ziaul; Das, Debasish Kumar
Type: Journal Article
Year: 2021