Groundwater Recharge Estimation Using Soil Moisture Balance Method for
Lange Watershed of Eastern Hararghe, Ethiopia
A Thesis Submitted to the School of Natural Resources and
Environmental Engineering, School of Graduate Studies
HARAMAYA UNIVERSITY
In Partial Fulfillment of the Requirements for the Degree of MASTER OF
SCIENCE IN SOIL AND WATER CONSERVATION ENGINEERING
Desta Befekadu
MAY 2015
Haramaya University, Haramaya
HARAMAYA UNIVERSITY
SCHOOL OF GRADUATE STUDIES
I hereby certify that I have read and evaluated this Thesis entitled Groundwater Recharge
Estimation Using Soil Moisture Balance Method for Lange Watershed of Eastern
Hararghe, Ethiopia ” prepared under my guidance by Desta Befekadu. I recommended that it
be submitted as fulfilling the thesis requirement.
Prof. Shoeb Quraishi (Dr. Eng.)
______________
Advisor
________________
Date
Signature
As member of the Board Examiners of the MSc. Thesis Open Defense Examination, I certify
that I have read and evaluated the Thesis prepared by Desta Befekadu and examined the
candidate. I recommend that it can be accepted as fulfilling the thesis requirement for the
degree of Master of Science in Soil and Water Conservation Engineering.
_________________
______________
_______________
Chairperson
Signature
Date
________________
________________
_______________
Internal Examiner
Signature
Date
_________________
________________
________________
External Examiner
Signature
Date
Final approval and acceptance of the Thesis is contingent upon the submission of its final copy
to the Council of Graduate Studies (CGS) through the candidate’s or school graduate
committee SGS).
ii
DEDICATION
This thesis manuscript is dedicated to my beloved wife Mulu, and daughter Simbo, for their
affection, love and generous moral support.
iii
STATEMENT OF THE AUTHOR
By my signature below, I declare and affirm that this Thesis is my own work. I have followed
all ethical and technical principles of scholarships in the preparation, data collection, and data
analysis compilation of this Thesis. Any scholarly matter that included in this Thesis has been
given recognition through citation.
This thesis is submitted in partial fulfillment of the requirements for a M.Sc. degree at
Haramaya University and deposited at the University Library to be made available to
borrowers under rules of the Library. I solemnly declare that this Thesis has not been
submitted to any other institution anywhere for the award of any academic degree, diploma or
certificate.
Brief quotations from this Thesis may be made without special permission provided that
accurate and complete acknowledgement of sources is made. Requests for permission for
extended quotations from or reproduction of this manuscript in whole or in part may be
granted by the Head of the School of Natural Resources and Environmental Engineering or the
dean of the School of Graduate Studies when in his or her judgment the proposed use of the
material is in the interests of scholarship. In all other instances, however, permission must be
obtained from the author.
Name:
Date:
_______________________
Signature: _______________________
________________________
School/Department:
________________________
iv
BIOGRAPHICAL SKETCH
The author was born in Oromiya National Regional State, West Wellega Zone, Ghimbi Town
in Sep 15, 1977. He attended his primary and secondary schools at Adiwa Dil Elementary
school from 1983/84, at Ghimbi compressive High school from 1991/92-1992/93 and Addis
Ababa Technical school from 1993/94-1995/96, respective. He joined Nazareth Technical
college now Adama University in July 1996 and graduated with diploma in Construction
Technology, and he joined Adama University in September 2003 and graduated in July 2006
with B.Sc. degree in Construction Technology. He was employed by different construction
and consulting companies and worked on several construction projects on different positions.
In 2011, he joined Haramaya University School of Graduate Studies for seeking M.Sc degree
in the field of Soil and Water Conservation Engineering.
v
ACKNOWLEDGMENTS
First and above all, I would like to praise almighty God, for his endless love, forgiveness and
help through all situations so that, I can complete my works. Then, I am very grateful
acknowledge to my advisor Prof. (Dr.Eng) Shoeb Quraishi for his valuable advice,
encouragement and critical comment during the research period.
I would also like to thank the Ethiopian Ministry of Water Resources, National Meteorological
Services Agency, for providing me important priceless data.
.
I would like to extend my gratitude to my friends, Mr. Mohammed Nuru, General Manager of
Afri Geo-information Engineering Plc. for his technical and material support during my study.
At last but not least, I would like to extend my deepest gratitude to my family, without their
encouragement and care this would not have happened.
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LIST OF ABBREVIATIONS AND ACRONYMS
AMC
Antecedent Moisture Content
ASW
Available Soil Water
BGS
British Geological Survey
CMB
Chloride Mass Balance
CN
Curve Number
DA
Development Agent
DEM
Digital elevation models
EHA
Ethiopian Hydro-geologist Association
ERA
Ethiopia Roads Authority
ETo
Reference Evapo-transpiration
FAO
Food and Agriculture Organization
FC
Field Capacity
GIS
Geographical Information System
GPS
Global Positioning System
GWTF
Groundwater Table Fluctuation
GW
Groundwater
HSG
Hydrologic Soil Group
HU
Haramaya University
IAH
International Association of Hydro-geologists
LULC
Land use and Land cover
NMSA
National Metrological Service Agency
PWP
Permanent Wilting Point
RAD
Radiation
SCS
Soil Conservation Service
SRTM
Shuttle Radar Topography Mission
UNECO
United Nations Educational, Scientific and Cultural Organization
US SCS
United State Soil Conservation Service
WTF
Water Table Fluctuation
vii
TABLE OF CONTENTES
Contents
Pages
STATEMENT OF THE AUTHOR
iv
BIOGRAPHICAL SKETCH
v
ACKNOWLEDGMENTS
vi
LIST OF ABBREVIATIONS AND ACRONYMS
vii
TABLES OF CONTENTES
ix
LIST OF TABLES
xii
LIST OF FIGURES
xiv
LIST OF TABLES IN THE APPENDIX
xv
LIST OF FIGURES IN THE APPENDIX
xvi
ABSTRACT
xvii
1.
INTRODUCTION
1
2.
LITERATURE REVIEW
4
2.1 Watershed and Watershed Delineation
4
2.1.1 Overview of GIS Technology
5
2.2. Groundwater
7
2.2.1 Definition
7
2.2.2. Groundwater management
8
viii
2.3. Groundwater Recharge
10
2.3.1. Factors affecting groundwater recharge
10
2.3.2. Importance of groundwater recharge estimation
11
2.4. Groundwater Recharge Estimation Methods
12
2.4.1. Physical methods for recharge estimation
14
2.4.1.1 Groundwater Table Fluctuation
15
2.4.1.2 Darcy’s law method
16
2.4.1.3 Soil moisture balance
17
2.4.2 Tracer technique
21
2.4.2.1 Chloride mass balance
3.
21
MATERIALS AND METHODS
22
3.1
Description of the study area
22
3.2
Data Collection and Analysis
24
3.2.1 Topographical data
24
3.2.2 Monthly rainfall data, Max and Min temperature, wind, Humidity,
sun shine data
24
3.2.3 Land use data and cropping patterns
24
3.2.4 Aquifer parameters
25
3.2.5 Data pre-processing and checking
27
3.2.6 Inflow to the Aquifer
29
3.2.7 Groundwater abstraction
21
3.2.8 Changes in soil moisture
34
ix
3.2.9 Changes in groundwater storage
4.
35
3.3 Final Data Analysis
36
RESULT AND DISCUSSION
37
4.1 Soil Physical properties
37
4.2. Change in Soil Moisture
39
4.3. Groundwater Discharge
41
4.3. 1. Water abstraction for Irrigation and Livestock
41
4.3.2. Water abstraction for domestic use
43
4.3.3. Evaporation from water table
45
4.3.4 Evapotranspiration
42
4.3.5. Evaporation from surface water
45
4.4. Groundwater Recharge
45
4.4.1. Runoff generated by the catchment
46
4.4.2. Precipitation
48
4. 5. Groundwater Level of the Well Field Area of the Catchment
49
4.6. Water Balance of Lake Lange Watershed
50
5. SUMMARY, CONCLUSIONS AND RECOMMENDATIONS
52
5.1. Summary and Conclusion
52
5.2. Recommendation
55
6. REFERENCES
56
7. APPENDICES
62
x
7.1 Appendix Tables
63
7.2 Appendix Figures
91
7.3 Appendix Questionnaire
95
xi
LIST OF TABLES
Table
1.
Pages
Location of the neighboring meteorological stations to Lange watershed
30
2. Derived rainfall data of Lange for the year 2013
31
3. Soil Texture Result of Lange Watershed
37
4. Bulk volumetric density determination for Profile probe Calibrations Result
38
5. Average monthly measured soil moisture (volumetric basis %)
40
6. Seasonal change in moisture for the watershed
41
7. Estimated water consumed by Livestock
42
8. Evapotransipiration loss from the watershed
44
9. Monthly surface evaporation from the water body
45
10. Runoff generated from the watershed
46
11. Water balance of Lange watershed
50
xii
LIST OF FIGURES
Figure
Pages
1. Lange watershed
23
2. The consistency analysis for Haramaya rainfall data
28
3. A. Excavated tubeless well
41
B. Excavate open channel
41
4. Mass flow curve of runoff for the year 2013
47
5.
48
Daily rainfall of the watershed
6. Water table fluctuation during study period
xiii
49
LIST OF TABLES IN APPENDIX
Appendix Table
Pages
1. ETo results after CROPWAT version 8.0
63
2. LULC of the watershed
64
3. Estimated curve numbers for LULC of the area
64
4. Single (time -averaged) crop coefficients, Kc, and mean maximum plant heights for
non stressed, well-managed crops in sub -humid climates (RH>45%,u2>2m/s) for use
with the FAO penman-Monteth ETo
65
5. Lange watershed wells
71
6. ETc of shrubs /chat
71
7. ETc of Eucalyptus tree in the watershed
72
8. ETc of grass
73
9. ETc of small vegetables
74
10. ETc of maize in the watershed
74
11. ETc of sorghum in the watershed
75
12. Daily meteorological data for January 2013
76
13. Daily meteorological data for February 2013
77
14. Daily meteorological data for March 2013
78
15. Daily meteorological data for April 2013
79
16. Daily meteorological data for May 2013
80
17. Daily meteorological data for Jun 2013
81
18. Daily meteorological data for July 2013
82
19. Daily meteorological data for August 2013
83
20. Daily meteorological data for September 2013
84
21. Daily meteorological data for October 2013
85
22. Daily meteorological data for November 2013
86
23. Daily meteorological data for December 2013
87
24. Water level data of well
88
25. Estimated specific yield for different geological formation
89
xiv
26. Estimated field capacity and permanent wilting point using soil texture
89
27. Some general guides to water intake of different class of animals.
90
xv
LIST OF FIGURES IN APPENDIX
Appendix Figures
Pages
1. Prior to particle size distribution determination
91
2. Installing access tube for profile probe
91
3. Soil moisture reading with profile probe
91
4. Core soil sampling for laboratory test purpose
92
5. Soil moisture measerment to calibrate profile probe
92
6. Mountainase area coverd by forest in the watershed
92
7. Water ponding at the lower area of the watershed
92
8. ERA area classification for antecedent moisture content of Ethiopia
93
9. Consistency analysis for Dire Dawa rainfall data
94
10. Consistency analysis for Girawa rainfall data
94
Appendix Questionnaire
Pages
Questionnaires
95
xvi
GROUNDWATER RECHARGE ESTIMATION USING SOIL MOISTURE BALANCE
METHOD FOR LANGE WATERSHED OF EASTERN HARARGHE, ETHIOPIA
ABSTRACT
Water especially groundwater is crucial to most nations, irrespective of their stage of
economic development. Worldwide large number of people, many industries and numerous
farmers depends their lives and livelihoods on this resource. Following the increase in
demand of water over-pumping of the groundwater has become one of the threats losing the
aquifer and creates great social influence in the area. To minimize the adverse consequences,
understanding the aquifer potential and its sustainability is of vital importance.
This research has been done with specific objective of watershed delineation and estimating
groundwater recharge estimation using soil moisture balance method .Soil moisture of the
watershed was measured using profile probe for both dry and rainy seasons, in the vadose
zone. Reference Evapotranspiration was estimated using CROPWAT 8 software. In the study
year, the estimated total sum of water abstractions both naturally and artificially was
4,642,689m3 while the total inflow to the aquifer was 5,307,464.m3. And water retained in the
vadose zones was estimated to be 218,943 m3 which was estimated from the change moisture
content in two seasons. The result of estimated recharge to aquifer in the study year
(increasing with 8.72%) was positive, but the value was too small to conclude confidently that
the aquifer is recharging or increasing, because the result could be easily changed as a few
increase in water abstraction increased or the rainfall of the area decreased due to certain
factor. So, all stakeholders shall get awareness and plan for the sustainable use of the water.
xvii