Geo-Environmental Impact Assessment Using Integrated GIS and Remote Sensing Technique: A Case Study on the Halele-Werabesa Stage I Hydropower Plant, West- Showa Jimma Zone, Oromia, Ethiopia By MEKDES ZENEBE KETEMA A Thesis Submitted to The School of Earth Sciences Presented In Partial Fulfillment the Requirement Degree of Master of Science in Remote Sensing and Geographic Information Systems (GIS) Addis Ababa University Addis Ababa, Ethiopia MAY, 2014 Geo-Environmental Impact Assessment Using Integrated GIS and Remote Sensing Technique: A Case Study on the Halele-Werabesa Stage I Hydropower plant, West Showa, Jimma Zone, Oromia, Ethiopia By, MEKDES ZENEBE A Thesis Submitted to the School of Earth Sciences Presented in Partial Fulfillment the Requirement Degree of Master of Science in Remote Sensing and Geographic Information Systems (GIS) Under the guidance of Dr. K.V. Suryabhagavan Asst. Professor, School of Earth Sciences Addis Ababa University, Addis Ababa Dr. Trufat H/Mariam Asst. Professor, School of Earth Sciences Addis Ababa University, Addis Ababa Addis Ababa University Addis Ababa, Ethiopia MAY, 2014 2 ADDIS ABABA UNIVERSITY SCHOOL OF GRADUATE STUDIES This is to certify that the thesis prepared by Mekdes Zenebe entitled: Geo-Environmental Impact Assessment Using Integrated GIS and Remote Sensing technique: a case study on the Halele-Werabesa Stage I Hydropower plant, West Showa, Jimma Zone, Oromia, Ethiopia and submitted in Partial Fulfillment the Requirement Degree of Master of Science in Remote Sensing and Geographic Information Systems (GIS) compiles with the regulation of the University and meets the accepted standards with respect to originality and quality. Signed by the Examining Committee: Examiner _______________________Signiture___________________Date__________ Examiner _______________________Signiture___________________Date__________ Advisor: Dr. K.V. Suryabhagavan Signiture___________________Date__________ Advisor: Dr. Trufat H/Mariam Signiture___________________Date__________ Chair of Department or Graduate Program Coordinator 3 ACKNOWLEDGEMENTS First and foremost, I want to thank the almighty God for giving me the chance, strength and courage to continue my study and for all things done in my entire life. Then, I would like to express my heartfelt gratitude to my advisors Dr. K.V. Suryabhagavan and Dr. Trufat H/Mariam for their profound guidance, valuable comments and constant encouragement throughout the entire period of this thesis. My sincere appreciation also goes to all my instructors and class mates of the Remote Sensing and GIS Program Engda, Abiy and Nigussie for sharing their experience, materials and valuable cooperation throughout my study. I wish to express my genuine thanks to Information Network Security Agency that gave me the scholarship opportunity to pursue my MSc degree. I am also thankful to the Ethiopian Electric Power and National Meteorological Service Agency (NMSA) from where I received all kinds of resource support. Last, but not least, words cannot express my feelings for my love, Nega and all my families. I am highly indebted to them for their blessing, guidance, advice, encouragement, and support. 4 Table of Contents CHAPTER ONE ............................................................................................................................ 1 INTRODUCTION ........................................................................................................................... 1 1.1 Background ............................................................................................................................ 1 1.2 Statement of the Problem ....................................................................................................... 2 1.3 Objective ................................................................................................................................ 3 1.3.1 General objective ............................................................................................................ 3 1.3.2 Specific objectives .......................................................................................................... 4 1.4 Significance of the study ........................................................................................................ 4 1.5 Scope of the study .................................................................................................................. 4 1.7 Limitation of the study ........................................................................................................... 5 1.8 Organization of the thesis ...................................................................................................... 5 CHAPTER TWO ........................................................................................................................... 6 LITERATURE REVIEW ................................................................................................................ 6 2.1. Hydropower Development in Ethiopia, ................................................................................ 6 2.2. Geo-Environmental studies definition, ................................................................................. 7 2.3. Geo-Environmental Hazards Affecting Dams ...................................................................... 8 2.3.1. Landslide ........................................................................................................................ 9 2.3.2 Landslide Susceptibility Analysis ................................................................................. 10 2.3.3 Soil erosion ................................................................................................................... 10 2.3.4 Mass Wastage ............................................................................................................... 11 2.4. Application of GIS and remote sensing in Geo-environmental impact assessment......... 12 CHAPTER THREE ..................................................................................................................... 15 MATERIALS AND METHODS ................................................................................................... 15 3.1 Description of the study area ............................................................................................... 15 3.1.1 Topography ................................................................................................................... 16 3.1.2 Climate .......................................................................................................................... 17 3.1.3 Hydrology ..................................................................................................................... 18 3.1.4 Population and Settlement ............................................................................................ 18 3.1.5 Geology ......................................................................................................................... 19 i 3.1.6 Soil ................................................................................................................................ 20 3.1.7 Vegetation Cover .......................................................................................................... 21 3.2 Methodology and Data Source ............................................................................................. 22 3.2.1 Data Type and Source ................................................................................................... 22 3.2.2. Material and Software .................................................................................................. 23 3.2.3. Method ......................................................................................................................... 23 3.2.3.1 Multivariate Approach: Logistic regression (LR) ...................................................... 24 3.2.3.2 Soil erosion risk model .............................................................................................. 25 CHAPTER FOUR ........................................................................................................................ 28 DATA ANALYSIS AND INTERPRETATION ........................................................................... 28 4.1 Landslide Susceptibility Mapping ....................................................................................... 28 4.1.1 Slope ............................................................................................................................. 28 4.1.2 Aspect ........................................................................................................................... 29 4.1.3 Lithology ....................................................................................................................... 30 4.1.4 Soil type ........................................................................................................................ 31 4.1.5 Drainage Density .......................................................................................................... 32 4.1.6 Lineament Density ........................................................................................................ 34 4.1.7 Land-use/ Land-cover ................................................................................................... 35 4.1.8 Landslide distribution ..................................................................................................