ASSESSMENT OF GROUNDWATER RESOURCES IN BOGRA DISTRICT USING GROUNDWATER MODEL MUHAMMAD ABDULLAH DEPARTMENT OF CIVIL ENGINEERING BANGLADESH UNIVERSITY OF ENGINEERING AND TECHNOLOGY OCTOBER, 2014 Assessment of Groundwater Resources in Bogra District using Groundwater Model by Muhammad Abdullah Student No. 0409042201 (F) In Partial fulfillment of the requirement for the degree of MASTER OF SCIENCE IN CIVIL ENGINEERING Department of Civil Engineering BANGLADESH UNIVERSITY OF ENGINEERING AND TECHNOLOGY, DHAKA October, 2014 The thesis titled Assessment of Groundwater Resources in Bogra District using Groundwater Model submitted by Muhammad Abdullah, Student No: 0409042201 (F), Session: April, 2009 has been accepted as satisfactory in partial fulfillment of the requirements for the degree of Master of Science in Civil Engineering (Geotechnical) on October 2014. BOARD OF EXAMINERS Dr. Syed Fakhrul Ameen Professor Department of Civil Engineering Chairman BUET, Dhaka (Supervisor) Dr. Mahbuboor Rahman Choudhury Member Assistant Professor (Co-Supervisor) Department of Civil Engineering BUET, Dhaka Member Dr. Tanvir Ahmed Assistant Professor Department of Civil Engineering BUET, Dhaka Member Dr. A.M.M. Taufiqul Anwar (Ex - officio) Professor and Head Department of Civil Engineering BUET, Dhaka Member Dr. A.F.M Afzal Hossain (External) Deputy Executive Director (P&D) Institute of Water Modelling (IWM) H-496, R-32, New DOHS, Mohakhali, Dhaka. ii CANDIDATE’S DECLARATION It is hereby declared that this thesis or any part of it has not been submitted elsewhere for the award of any degree or diploma. Muhammad Abdullah iii ACKNOWLEDGEMENT Foremost, I would like to express my sincere gratitude to my supervisor Dr. Syed Fakhrul Ameen, Professor, Department of Civil Engineering, BUET for his special support of my M.Sc thesis, for his patience, motivation, enthusiasm, and immense knowledge. I also express profound gratitude to my co-supervisor Dr. Mahbuboor Rahman Choudhury, Assistant Professor, Department of Civil Engineering, BUET for his continuous guidance and encouragement for the research. His nice and careful guidance, constructive suggestions immensely contributed to the improvement of this thesis. Furthermore, I would like to thank Institute of Water Modelling and their experts, specially to Md. Atiqur Rahman, Junior Engineer, Irrigation Management Division, Institute of Water Modelling for his kind help and fruitful discussion about the groundwater model. Last but not the least; I would like to thank my wife for supporting me spiritually throughout the research. iv ABSTRACT Groundwater is the largest source of usable fresh water in the world. Domestic & irrigation water needs are being met in many parts of the world using groundwater, especially where surface water supplies are not available. The use of groundwater compared to surface water is much higher in north-western districts in Bangladesh. Due to over abstraction in the recent years of north-western districts, groundwater is lowering at an alarming rate. The objective of the study is to analyze the trend & extent of groundwater table due to expanding status of water demand. To assess groundwater resources of Bogra district due to future water demands, change in crop pattern & increase of water demand is considered. MIKE SHE hydrologic model has been used to simulate fluctuating water table to assess groundwater resources. MIKE SHE is a deterministic, physics-based, distributed & integrated hydrologic model, deals with entire hydrologic cycle. Precipitation, evapotranspiration & groundwater abstraction are fundamental hydro-meteorological & hydro-geological inputs. The rainfall data was obtained from daily records of eight BWDB stations; evapotranspiration data was obtained from only one BWDB station in the study area. Groundwater abstraction is assumed as the integration of irrigation & domestic water needs. The model inputs regarding land use classification, topography & lithologic layers underneath the upper soil were incorporated directly from IWM. Few input data has been projected using suitable projection models. Model has been simulated within the period from 2006 to 2030. The simulated phreatic surface & their trends have been compared with the observed levels & their trends. Finally, the model has been adjusted using calibration parameters. Lower phreatic surface & higher depletion rate is found in south-western upazilas of Bogra district. The depletion rates vary from 0.00 to 2.92 cm/year for mean depth of phreatic surface. Maximum depth of phreatic surface varies from 1.20 cm/year to 14.45 cm/year. After a drought rainfall year, lower phreatic surface is observed. However this is regained in subsequent years with an average rainfall. Contribution to groundwater recharge in Bogra district is mainly due to rainfall. v TABLE OF CONTENTS ACKNOWLEDGEMENT …………………………………………………….. iv ABSTRACT ...………………………………………………….………………. v TABLE OF CONTENTS ……………………………………………………… vi LIST OF TABLES …………………………………………………………….. viii LIST OF FIGURES ...….……………………… …………………………….. ix ACRONYMS AND ABBREVIATIONS …………………………………….. xiii CHAPTER 1 INTRODUCTION....................................................... 2 1.1 General .............................................................................................................. 2 1.2 Objectives of the Study .................................................................................... 3 1.3 Structure of the Thesis ..................................................................................... 4 CHAPTER 2 LITERATURE REVIEW .......................................... 2 2.1 General .............................................................................................................. 2 2.2 Developments of Hydrologic Model ................................................................ 2 2.3 Basic Theory of Modelling ............................................................................... 7 2.4 MIKE SHE Hydrologic Model ...................................................................... 10 2.5 Researches Related to Groundwater Resources of the Study Area ........... 13 CHAPTER 3 HYDROLOGICAL DATA COLLECTION ............ 2 3.1 General .............................................................................................................. 2 3.2 Data Collection for MIKESHE Hydrologic Model ..................................... 18 3.2.1 Hydrometeorology of the study area ............................................................... 19 3.2.2 Hydrogeology of the study area ...................................................................... 24 3.2.3 Topography of the study area .......................................................................... 32 3.2.4 Lithology of the study area .............................................................................. 33 CHAPTER 4 DATA PROCESSING AND MODEL SETUP ...... 38 4.1 General ............................................................................................................ 38 vi 4.2 Prediction of Data up to Year 2030 ............................................................... 38 4.2.1 Precipitation ..................................................................................................... 38 4.2.2 Evapotranspiration ........................................................................................... 41 4.2.3 River water level.............................................................................................. 41 4.2.4 Groundwater level at model boundary ............................................................ 41 4.2.5 Irrigation water demand .................................................................................. 42 4.2.6 Domestic water demand .................................................................................. 43 4.3 Model Set Up ................................................................................................... 44 4.3.1 Model build-up ................................................................................................ 45 4.3.2 Model calibration............................................................................................. 53 4.3.3 Model validation .............................................................................................. 56 CHAPTER 5 RESULTS AND DISCUSSIONS ............................. 58 5.1 General ............................................................................................................ 58 5.2 Groundwater Level at Study Area Boundary Wells (Period: 2005-2012) 5.3 Predicted Phreatic Surface using MIKE SHE Hydrologic Model for Present Crop Pattern ..................................................................................... 62 5.3.1 Predicted trend and depletion rate of phreatic surface (period: 2006 to 2030) 63 5.3.2 Annual fluctuation of phreatic surface with rainfall & abstraction ................. 66 5.4 Predicted Phreatic Surface using MIKE SHE Hydrologic Model for Change in Crop Pattern ................................................................................. 72 5.4.1 Predicted depth of phreatic surface ................................................................. 72 5.4.2 Predicted depletion of groundwater level after consecutive drought years ..... 74 5.4.3 Depth of phreatic surface above suction limit of hand tube well .................... 79 5.5 Assessment of Groundwater Resources in Bogra District .......................... 82 5.5.1 Water balance components .............................................................................