1st Edition

Role of Sediment Transport in Operation and Maintenance of Supply and Demand Based Irrigation Canals: Application to Machai Maira Branch Canals UNESCO-IHE PhD Thesis

By Sarfraz Munir Copyright 2011
    286 Pages
    by CRC Press

    286 Pages
    by CRC Press

    This work describes the role of sediment transport in the operation and maintenance of demand-based downstream controlled irrigation canals. Sediment deposition in these irrigation canals severely affects the operation of the automatic flow control system. The book also discusses sediment transport modelling in irrigation canals. A simplified 1-D mathematical model SETRIC (SEdiment TRansport in Irrigation Canals) has been improved with the inclusion of downstream control component for the downstream controlled irrigation canals. Based on field measurements and sediment transport modelling, a number of approaches have been proposed for sediment management in such irrigation canals by improvement in their design and operation. This book will be of interest to Irrigation Engineers and Managers, Hydraulic Engineers, Water Resources Engineers and Managers, Civil Engineers, and Agricultural Engineers.

    1. INTRODUCTION AND BACKGROUND
    1.1 BACKGROUND
    1.2 RATIONALE OF THE STUDY
    1.3 SCOPE OF THE STUDY
    1.4 RESEARCH QUESTIONS
    1.5 RESEARCH HYPOTHESIS
    1.6 OBJECTIVES
    1.7 INTRODUCTION OF THE THESIS

    2. INDUS BASIN IRRIGATION SYSTEM IN PAKISTAN
    2.1 GENERAL INFORMATION ABOUT PAKISTAN
    2.2 SOCIO-ECONOMIC SETTINGS OF THE COUNTRY
    2.3 WATER RESOURCES
    2.4 INDUS BASIN IRRIGATION SYSTEM
    2.5 HISTORY OF IRRIGATION IN THE INDUS BASIN

    3. SEDIMENT TRANSPORT AND FLOW CONTROL IN IRRIGATION CANALS
    3.1. GENERAL INFORMATION ON SEDIMENT TRANSPORT AND MODELLING
    3.1.1 Incipient motion
    3.1.2 Bed load sediment transport
    3.1.3 Suspended sediment transport
    3.1.4 Total sediment load
    3.2. EVALUATION OF SEDIMENT TRANSPORT FORMULAE
    3.3. SEDIMENT TRANSPORT MODELLING
    3.4. SEDIMENT TRANSPORT MODELLING IN IRRIGATION CANALS
    3.5. SEDIMENT MANAGEMENT IN IRRIGATION CANALS
    3.5.1 Sediment control at intakes
    3.5.2 Sediment diverters (silt excluders)
    3.5.3 Sediment ejectors
    3.5.4 Settling basins
    3.5.5 Sediment control by canal design approach
    3.5.6 Operation and maintenance of silt affected irrigation canals
    3.6. FLOW CONTROL IN IRRIGATION CANALS
    3.6.1 Upstream control
    3.6.2 Proportional control
    3.6.3 Downstream control
    3.7. HYDRAULICS OF DOWNSTREAM CONTROL SYSTEM
    3.8. DESIGN CRITERIA
    3.9. FLOW CONTROL ALGORITHMS
    3.9.1. Supervisor Control and Data Acquisition System
    3.9.2. Proportional Integral Derivative (PID) control

    4. SEDIMENTATION IN TARBELA RESERVOIR AND ITS EFFECTS ON PEHURE HIGH LEVEL CANAL
    4.1. SEDIMENTATION OF RESERVOIRS IN THE WORLD
    4.2. TARBELA DAM
    4.3. SEDIMENTATION IN TARBELA RESERVOIR
    4.3.1 Water availability at Tarbela Dam
    4.3.2 Sediment inflow to Tarbela Reservoir
    4.3.3 Tarbela Reservoir operation
    4.3.4 Sediment trapping in the reservoir and status of storage capacity
    4.3.5 Accumulated sediment deposition in Tarbela Reservoir
    4.4. DEVELOPMENT OF SEDIMENT DELTA IN A RESERVOIR
    4.4.1 Siltation process in reservoirs
    4.4.2 Formation of a delta
    4.4.3 Factors affecting sediment delta movement
    4.4.4 Reworking of the delta
    4.5. ANALYSIS OF THE SEDIMENT DELTA IN TARBELA RESERVOIR
    4.6. PROSPECTS OF SEDIMENT MANAGEMENT
    4.7. TARBELA DAM AND PEHURE HIGH LEVEL CANAL

    5. HYDRODYNAMIC BEHAVIOUR OF MACHAI MAIRA AND PEHURE HIGH LEVEL CANALS
    5.1. BACKGROUND
    5.2. OBJECTIVES OF THE HYDRODYNAMIC MODELLING
    5.3. METHODS AND MATERIALS
    5.3.1. Irrigation infrastructure
    5.3.2. System operations
    5.3.3. Crop Based Irrigation Operations (CBIO)
    5.3.4. Discharge and water level controls
    5.3.5. Secondary offtakes operation
    5.3.6. Modelling canal operations
    5.3.7. Calibration of the model
    5.4. RESULTS AND DISCUSSION
    5.4.1. Model calibration and validation
    5.4.2. Steady state simulations
    5.4.3. Performance of Proportional Integral discharge controllers
    5.4.4. Effect of amount and location of discharge refusal on discharge control
    5.4.5. Testing of CBIO schedules
    5.4.6. Gate responses

    6. SEDIMENT TRANSPORT IN MACHAI AND MAIRA BRANCH CANALS
    6.1. METHODOLOGY OF FIELD DATA COLLECTION
    6.1.1. Measurement methods
    6.1.2. Fieldwork arrangement
    6.2. IRRIGATION WATER SUPPLY TO USC-PHLC SYSTEM
    6.3. WATER DISTRIBUTION TO SECONDARY OFFTAKES
    6.4. SEDIMENT INFLOW TO THE SYSTEM
    6.5. RESULTS FROM MASS BALANCE STUDIES
    6.5.1. Mass balance in July 2007
    6.5.2. Mass balance in December 2007
    6.5.3. Mass balance in July 2008
    6.6. OFFTAKES SEDIMENT WITHDRAWAL
    6.7. MORPHOLOGICAL CHANGES IN THE CANALS
    6.7.1. Cross-sectional survey in January 2007
    6.7.2. Cross-sectional survey in July 2007
    6.7.3. Cross-sectional survey in January 2008

    7. CANAL OPERATION AND SEDIMENT TRANSPORT
    7.1. BACKGROUND
    7.2. SIMULATION OF IRRIGATION CANALS (SIC) MODEL
    7.2.1. Topography module
    7.2.2. Steady flow module
    7.2.3. Unsteady flow module
    7.2.4. Sediment module
    7.3. SEDIMENT TRANSPORT MODEL SET UP
    7.3.1. Sensitivity analysis
    7.3.2. Comparison between sediment transport predictors
    7.3.3. Model calibration and validation
    7.4. SCENARIO SIMULATION
    7.4.1. Simulations under existing conditions of water and sediment discharge
    7.4.2. Sediment transport under design discharges with existing sediment concentration
    7.4.3. Sediment transport under CBIO with existing sediment concentration
    7.5. SEDIMENT TRANSPORT IN PHLC
    7.5.1. Sediment transport capacity in PHLC
    7.5.2. Sediment transport capacity in the canals downstream of RD 242
    7.6. SCENARIO SIMULATIONS WITH TARBELA EFFECT
    7.6.1. Sediment transport at full supply discharge
    7.6.2. Sediment transport at existing discharge conditions
    7.6.3. Sediment transport under CBIO
    7.7. EFFECT OF FLOW CONTROL ON SEDIMENT TRANSPORT
    7.8. SEDIMENT CONCENTRATION ARRIVING AT RD 242 FROM THE PHLC
    7.9. COMBINED SEDIMENT CONCENTRATION AT CONFLUENCE FOR CBIO
    7.10. SEDIMENT TRANSPORT DOWNSTREAM OF RD 242 WITH COMBINED SEDIMENT INFLOW FROM MACHAI BRANCH CANAL AND PHLC
    7.10.1. At design discharge
    7.10.2. At existing discharge
    7.10.3. At Crop Based Irrigation Operations

    8. DEVELOPMENT OF DOWNSTREAM CONTROL COMPONENT IN SETRIC MODEL
    8.1. BACKGROUND
    8.2. RATIONALE
    8.3. SETRIC MODEL
    8.3.1. Water flow calculations
    8.3.2. Roughness calculations
    8.3.3. Determination of roughness on the side walls
    8.3.4. Galappatti’s depth integrated model
    8.3.5. Separation of bed and suspended load
    8.3.6. Concentration downstream of inflow and outflow points
    8.3.7. Morphological changes in the bed
    8.3.8. Boundary conditions
    8.4. IMPROVEMENTS IN THE SETRIC MODEL
    8.4.1. AVIS and AVIO gates
    8.4.2. Gate index of AVIS/AVIO gates
    8.4.3. Hydraulics of AVIS/AVIO gates
    8.4.4. Discharge computation
    8.5. COMPUTATION PROCEDURE IN SETRIC MODEL FOR DOWNSTREAM CONTROL
    8.6. APPLICATION OF THE SETRIC MODEL TO AUTOMATICALLY DOWNSTREAM CONTROLLED IRRIGATION CANAL
    8.6.1. Calibration and validation of the model
    8.7. FLOW SIMULATIONS
    8.7.1. Flow simulation under design flow conditions
    8.7.2. Flow simulation at 50% of full supply discharge
    8.7.3. Flow simulation at 75% of full supply discharge
    8.8. SEDIMENT TRANSPORT SIMULATIONS
    8.8.1. Calibration and validation of SETRIC Model for sediment transport
    8.8.2. Sediment inflow to the irrigation canal under study
    8.8.3. Under design discharge with existing sediment inflow
    8.8.4. Under existing water and sediment inflow
    8.8.5. Under CBIO and existing sediment inflow

    9. MANAGING SEDIMENT TRANSPORT
    9.1. TRADITIONAL APPROACH OF SEDIMENT MANAGEMENT IN INDUS BASIN IRRIGATION SYSTEM
    9.2. DESILTING OF IRRIGATION CANALS
    9.3. EFFECT OF SEDIMENT TRANSPORT ON UPSTREAM CONTROLLED IRRIGATION CANALS
    9.4. EFFECT OF SEDIMENT TRANSPORT ON THE HYDRAULIC PERFORMANCE OF DOWNSTREAM CONTROLLED IRRIGATION CANAL
    9.4.1. Effect of sediment deposition at the automatic flow releases
    9.4.2. Effect of secondary offtakes operation on sediment transport capacity
    9.5. EFFECT OF DIFFERENT OPERATION SCHEMES ON SEDIMENT TRANSPORT
    9.5.1. Effects of design discharge
    9.5.2. Effects of existing discharge
    9.5.3. Effect of different options of CBIO on sediment transport
    9.6. MANAGEMENT OPTIONS
    9.6.1. Operation under different discharge conditions
    9.6.2. Sediment transport under CBIO with increased sediment discharge from the Tarbela Reservoir
    9.6.3. Target water level and sediment transport
    9.6.4. Decrement setting and AVIS gates’ response
    9.6.5. Grouping and clustering of offtakes
    9.6.6. Offtakes close to cross regulators

    10. EVALUATION
    10.1. SEDIMENTATION IN TARBELA RESERVOIR AND PHLC
    10.2. HYDRODYNAMIC BEHAVIOUR OF THE IRRIGATION CANALS
    10.3. FLOW AND SEDIMENT TRANSPORT IN THE IRRIGATION CANALS
    10.4. SEDIMENT TRANSPORT MODELLING
    10.5. DEVELOPMENT OF DOWNSTREAM CONTROL COMPONENT IN SETRIC MODEL
    10.6. MANAGING SEDIMENT TRANSPORT
    10.7. CONCLUSIONS AND WAY FORWARD

    REFERENCES
    LIST OF SYMBOLS
    ACRONYMS

    APPENDICES
    A. SEDIMENT TRANSPORT RELATIONSHIPS UNDER EQUILIBRIUM CONDITIONS
    B. THE SAINT-VENANT EQUATIONS AND THEIR SOLUTION
    C. ONE DIMENSIONAL CONVECTION DIFFUSION EQUATION AND ITS SOLUTION IN UNSTEADY STATE FLOW CONDITIONS
    D. MODIFIED EINSTEIN PROCEDURE FOR COMPUTATION OF TOTAL SEDIMENT LOAD FROM FIELD MEASUREMENTS
    E. CROP WATER REQUIREMENTS AND CROP BASED IRRIGATION OPERATIONS
    F. SEDIMENT INFLOW AT MACHAI BRANCH HEADWORKS
    G. SEDIMENT INFLOW AT RD 242
    H. RESULTS OF EQUILIBRIUM MEASUREMENTS

    SAMENVATTING
    ABOUT THE AUTHOR

    Biography

    Sarfraz Munir (Narowal, Pakistan, 1974), received his Bachelor and Master degrees in Agricultural Water Management from the North Western Frontier Province (now Khyber Pakhtunkhwa) Agricultural University, Peshawar, Pakistan in 1997 and 2000 respectively. He served from 1999 to 2009 in the International Water Management Institute (IWMI) in Pakistan. He has been engaged in a number of projects on performance assessment of irrigation systems in Pakistan, agricultural water management, environmental impact assessment of wastewater irrigation and the evaluation of modernized irrigation systems. His assignments included field measurements for agricultural and environmental water management like flow measurements in irrigation canals, hydraulic structures' and downstream gauges' calibration, longitudinal and cross-sectional surveys in irrigation canals, groundwater observations, installation of necessary equipment for surface water and groundwater observations, in situ water quality measurements, laboratory analysis of plant, soil and water quality, socio-economic surveys, hydraulic modelling, synthesis of field data and report writing. From 2006 untill 2011 he conducted his PhD study in Hydraulic Engineering-Land and Water Development Core, UNESCO-IHE, Institute for Water Education, Delft, the Netherlands.