Environmental Impact of Teesta Barrage on the Command Area in Bangladesh

Abstract

Bangladesh Water Development Board (BWDB) has implemented Teesta Barrage Irrigation Project in 1994. The objectives of this mega project were flood control and creation of supplementary irrigation facilities for an area of 1,54,250 ha under the greater Rangpur district. This study was conducted to identify the environmental impact of Teesta Barrage Irrigation Project on agriculture, groundwater and rainfall in the project area by trend analysis of two periods: before and after project. For trend analysis 22 years (1983- 2004) ground water table and 20 years (1984-2003) rainfall data were used. From ground water data analysis, it is found that seasonal mean ground water table was up in post-project period (1994-2005) of Teesta Barrage Irrigation Project and level was down in pre-project period (1982-1993). The mean differences of ground water table of these two periods was significantly different (0.01% level) in all six seasons of summer, rainy, autumn, late autumn, winter, spring and summer. Therefore, it is concluded that Teesta Barrage Irrigation Project has positive impact on ground water resources and improved the ground water table in the command area. From rainfall data analysis, it is observed that mean rainfall in post-project period (1994-2003) of Teesta Barrage Irrigation Project was increased in all six seasons in the study area compare to mean rainfall of pre-project period (1984-1993). However, the mean difference rainfall between the periods (1984-1993) & (1984-2003) was found significant only in winter season. Therefore, it is concluded that Teesta Barrage Irrigation Project has positive impacts on rainfall pattern in the project area. As per respondents’ opinion, Teesta Barrage Irrigation Project has also positive impacts on the following environmental components. i) Increased food production for HYV-Boro and T-aman cultivation ii) Increased fruiting plants and social forest plantation iii) Increased drinking water availability iv) Decreased water born diseases v) Improved income and standard of life of local people However, Teesta Barrage Irrigation Project has reduced the open fisheries in the project area. Jute and aus cultivation are dramatically reduced in this area.