Groundwater Depletion and its Sustainable Management in Barind Tract of Bangladesh

Abstract

Background and Objective: Groundwater is one of the most important renewable resources which play a great role into livelihood, economies and agriculture sector in a nation. However, this valuable resource has been defected through various ways. This study aimed to investigate the effect of over exploitation of groundwater on Barind Tract area and its probable impact on the environment. The effect of groundwater fluctuation due to deep tubewells installed in the study area for irrigation has also been investigated. The study area was Chapai Nawabganj district in Barind Tract area which is located in North-western part of Bangladesh. Materials and Methods: The study area consisted of five upazilas namely Nawabganj, Shibganj, Nachole, Gomastapur and Bholahat. Results: The experimental data were analyzed and the result revealed that the minimum water level depletion recorded was about 6.33 m below the surface at Shibgonj Upazila in 2008 and maximum water level depletion recorded was about 109.40 m below the surface at Nachol upazila in 2014. A 10-year rainfall data of the said district showed that the maximum annual rainfall recorded was 2029 mm in 2007 and since then rainfall was gradually decreased. The highest annual rainfall received in the area was 1793 mm in 2007 and the lowest was 1025 mm in 2010 in the district. The average rainfall received in Chapai Nawabganj district was 1372 mm during 2007-2016. A good trend of water table fluctuations of Chapai Nawabganj district was found during 2007-2016. Conclusion: From the analysis results, a good relation between rainfall and water table fluctuations can be observed where the groundwater table was possibly recharged through the rainfall. The overall yearly water table declining trend indicates that the unsustainable withdrawal of groundwater for irrigation purposes played a vital role in groundwater table depletion in the study area. Moreover, groundwater level fluctuation depended on the extraction and recharge of the area.