Rainfall Data and Analysis of Auja Al -Timsah Catchment and Relation with Springs Discharge By Adel Yasin Supervision Committee: Dr. Marwan Ghanim Main Supervisor Dr. Ziad Al Mimi Co-Supervisor Dr. ‘Amer Mar’i Member A research proposal submitted in partial fulfillment of the requirements for the master degree in water engineering from the Faculty of graduate studies at Birzeit University- Palestine June 2004 Rainfall Data Analysis of Auja Al-Timsah Catchment and Relation with Springs Discharge By Adel Yasin Student Number 995159 This thesis was prepared under the main supervision of Dr. Marwan Ghanim and approved by all members of the examination committee. Dr. Marwan Ghanim …………………………... (Chairman of committee) Dr. Ziad Al Mimi …………………………… (Co-Supervisor) Dr. ‘Amer Mar’i …………………………… (Member) Date of defence : 10/06/2004 The findings , interpretations and the conclusions expressed in this study don’t necessarily express the views of Birzeit University, the views of the individual members of the MSc committee or the views of their representative employers. ACKNOWLEDGMENTS The author owes a great dept of graduate to Dr. Marwan Ghanem for his great assistance in supervising this work, great advice, useful comments and continuous guidance. My special thanks are extended to Palestinian Water Authority for the valuable data and allowing to use their data , systems and the library. My special thanks are to Mr Usama naser, Omar zayed and Mrs Sawsan Asbah for their help and valuable advice. Finally, I would like to thank my family for their encouragement and support. Adel S. Yasin i ABSTRACT Hydrology of Auja al Timsah Catchment was the main issue studied in this research, in terms of rainfall and springs discharge. Auja al Timsah Catchment was chosen specifically for this study since it forms the main recharge area for the western aquifer basin , also there are more than 150 Palestinian communities depends directly on rainfall, or depends on groundwater wells and springs to get their needs from fresh water for drinking and irrigation purposes. The main goal of this study is to screen, estimate and analyze the rainfall data and find the relationship with spring's discharges. The screened and analyzed data will be the main input for groundwater, surface water, and recharge models used to estimate water budget and estimate yields of aquifers. First, the research started by collecting data from different water institutions, second by screening the data using different tests like time series, tabular comparison, spatial homogeneity, double mass curve, t-test, f-test and trend analysis tests applied for daily, monthly and annual data sets. Computer programs were utilized and modified to screen the data and estimate the missing. The data sets were analyzed to evaluate the adequacy of rainfall network and to analyze the water quantities in terms of areal rainfall, wet and dry days, rainfall depth, frequency analysis and extreme analyses, k-analysis, ii seasonal analysis, temporal and spatial and trend analysis. Finally springs data were analyzed in the major springs in terms of discharge quantities and relationship with rainfall data. The results of the study indicate that the quality of rainfall data is poor in terms of measurements, instrumentations, network distribution, spatial and temporal coverage. The rainfall quantities is affected spatially by topography features, geographical location and distance from the coast, the spatial variety is high and caused by small, intense and convective storms. On the other hand the temporal trend of rainfall shows changes in the annual and seasonal patterns. Also the results of the study show a strong relationship between rainfall and spring discharges, where the effect of rainfall in recharging the aquifer starts to appear after two months. Finally, in order to conduct the hydrological and modeling studies, the data screening and analysis techniques applied in this study can be applied in other catchments, also other further detailed studies are recommended. iii TABLE OF CONTENTS ACKNOLEDGMENT i ABSTRACT ii TABLE OF CONTENTS iv LIST OF TABLES vi LIST OF FIGURES viii ACRONYMS AND ABBREVIATIONS ix 1 INTRODUCTION 1 1.1 Background 1 1.2 Aims and Objectives 2 2 LITERATURE REVIEW 3 2.1 Definition of Precipitation 3 2.2 Formation of Precipitation 3 2.3 Sitting of the Raingauges 4 2.4 Calibration, Maintenance and Inspection 5 2.5 Precipitation Measurement 5 2.5.1 Point Measurement and Instruments 6 2.5.2 Areal Measurement 7 2.6 Previous studies 8 3 METHODOLOGY 10 3.1 Study Area 10 3.1.1 Location and Population 10 3.1.2 Climate 10 3.1.3 Topography 14 3.2 Geology of the Study area 14 3.2.1 Lithostratigraphy 14 3.2.2 Karstification 18 3.3 Hydrogeology of the study area 19 3.3.1 Aquifer System 19 3.3.2 Drainage System 21 3.3.3 Recharge 22 3.4 Data collection 22 3.5 Data Assessment and Screening 23 3.6 Data Analysis and Interpretation 23 3.7 Expected Results and Output 24 4 MONITORING NETWORK AND QUALITATIVE DATA 25 4.1 Rainfall Monitoring System 25 4.2 Availability of the Data 25 iv 4.3 Quality of the Measured Rainfall Data 26 4.4 Rainfall Data Screening and Processing 30 4.4.1 Daily Rainfall Data Screening 33 3.4.2 Monthly Rainfall Data Screening 46 4.4.3 Yearly Rainfall Data Screening 50 4.5 Data Completion and Estimation 54 4.5.1 Data Completion through Spatial Homogeneity Test 55 on Daily Basis 4.5.2 Data Completion through Linear Regression on 55 Monthly Basis 4.6 Discussion of Results 57 5 Monitoring Network Design and Rainfall Analysis 57 5.1 Network Analysis 57 5.1.1 Instrumentations 57 5.1.2 Spatial Distribution 57 5.1.3 Time Coverage 60 5.1.4 Evaluation of the Existing Network 61 5.2 Rainfall Analysis 61 5.2.1 Determination of Areal Rainfall 61 5.2.2 Wet and Dry days 67 5.2.3 Rainfall Depth 68 5.2.4 Frequency Analysis of Extremes and Exceedence 69 5.2.5 k-Analysis of Rainfall Data 76 5.2.6 Monthly Rainfall Analysis 79 4.2.7 Yearly Rainfall Analysis 84 5.3 Discussion of Results 86 6 Spring Discharges and Relation With Rainfall 89 6.1 Springs and Monitoring Network 89 6.2 Measurements of Springs 92 6.3 Quantity analysis of springs Discharges 93 6.3.1 Annual Spring flow variation 93 6.3.2 Monthly spring Flow variation 93 6.3 Major Springs 95 6.4 Rainfall-Flow Relation 97 6.4.1 Relationship Between Discharge and Rainfall on 98 Annual Scale 6.4.2 Relationship Between Discharge and Rainfall on 99 Monthly Scale 6.5 Discussion of Results 100 7 Conclusions and Recommendations 102 7.1 Conclusions 102 v 7.2 Recommendations 105 8 References 107 APPENDICIES ABSTRACT IN ARABIC vi List of Tables Number Title Page Table 3.1 Stratigraphy and aquifer System in the study Area 20 Table 3.2 Major Wadis and Potential Runoff 22 Table 4.1 Data Availability in the Study area 26 Table 4.2 Base and Surrounding stations used in Spatial Homogeneity 38 Test. Table 4.3 Screening of Rainfall Data Using spatial homogeneity Test 40 on Daily Bases Table 4.4 Screening of Daily Rainfall Data Using Meteorological Office 43 Procedure Table 4.5 Representative Tabular Comparison Table 45 Table 4.6 Results in Percentages for the Processed Data 46 Table 4.7 Screening of Monthly Rainfall using Metrological Office 50 Procedure Table 4.8 Annual Data Screening by Using Trend, t-test and f-test 54 Table 4.9 Data Completion using Linear Regression 56 Table 5.1 Rainfall Stations Density by Topographic Zones 58 Table 5.2 Rainfall Stations Density by Outcrops 58 Table 5.3 Rainfall Stations Density By Precipitation Zones 60 Table 5.4 Areal Rainfall By Different Methods 64 Table 5.5 Average Wet and Dry Days 67 Table 5.6 Depth of Daily Rainfall(mm) 68 Table 5.7 The Maximum Average Daily Extremes Recorded 70 Table 5.8 The Maximum daily Extremes Recorded in each Station 70 Table 5.9 Annual and Partial series Analysis (Gumbel ) 73 Table 5.10 Comparison between Gumbel and Exponential Distributions 73 Table 5.11 Totals of k-Day Period for K=1,2,5 and,10 Days 79 Table 5.12 The Average Monthly Rainfall (Extreme Values) 80 Table 5.13 Maximum Monthly rainfall in Each station 95 Table 6.1 Geological Characteristics of the Major Springs 96 Table 6.2 Maximum and Minimum Monthly Flow in the Major Springs. 96 Table 6.3 Maximum and Minimum Yearly Flow in the Major Springs 96 Table 6.4 Relation Between Rainfall and Discharge on monthly Scale 100 vii List of Figures Number Title Page Figure 2.1 Standard Storage Raingauges 7 Figure 2.2 Principle of Tibbing-bucket Mechanism 7 Figure 3.1 Location map of the study area 11 Figure 3.2 Palestinian communities and Israeli Settlements in 12 the Study Area Figure 3.3 Topography zones of the Study Area 15 Figure 2.4 Geological Outcrops of the study Area 16 Figure 4.1 Rainfall Stations Network in the Study Area 28 Figure 4.2 Three characteristics Rainfall Time Series 32 Figure 4.3 Time Series Data Al Mazra'ah Al Sharqiya 34 Figure 4.4 Comparison between Two Adjacent stations 35 Figure 4.5 Comparison among three adjacent Stations 35 Figure 4.6 Double Mass Analysis of January (Hajja Station) 45 Figure 4.7 Residual Mass Analysis of January (Hajja Station) 47 Figure 4.8 Comparison between Recorded and Estimated 56 Data ( Bir Zeit station Figure 5.1 Geographical distribution of Rainfall Network 59 Figure 5.2 Thiessen Area Distribution in the Study Area 65 Figure 5.3 Isoytal Map for the Period 1988/1997 66 Figure 5.4 Extreme Analysis Comparing Full and partial 74 Extremes with Measured Data Figure 5.5 Frequency Distribution For Different K 77 Figure 5.6 Cumulative Frequency Curves for Different 78 Durations Figure 5.7 Depth- Duration-Frequency