I= INVESTIGATION OF OPTIMAL OPERATION STRATEGIES FOR IRRIGATION SYSTEMS
Pakistan Research Repository Home
 

Title of Thesis
INVESTIGATION OF OPTIMAL OPERATION STRATEGIES FOR IRRIGATION SYSTEMS

Author(s)
Muhammad Zubair Khan
Institute/University/Department Details
University Of Engineering And Technology, Taxila
Session
2006
Subject
Civil and Environment Engineering
Number of Pages
143
Keywords (Extracted from title, table of contents and abstract of thesis)
optimal operation strategies, irrigation systems, crop based irrigation operations, upstream control irrigation, downstream control irrigation, canalman

Abstract
The operation of an upstream and downstream control irrigation systems was studied at main, secondary and tertiary levels with regard to water saving. The study focused on the investigation of the existing operational practices and evaluation of alternate operational options. The main goal was to study water saving strategies in downstream control systems. The study is based on the integrated use of different models and approaches at different levels of an irrigation system. At main canal level Crop Based Irrigation Operations (CBIO) model was applied as a water saving strategy. The model computes irrigation rotations among secondary canals in a downstream control system. It was applied to a real system of irrigation named as Maira Branch of Upper Swat Canal, Pakistan. For investigations at secondary level, Canalman model was applied to five Secondary canals and one main branch of the Upper Swat Canal Irrigation System. The main operational strategies evaluated at secondary level were night closure of secondary canals in the periods of low irrigation demand and operation of the canals at reduced discharges. Performance assessment was made to determine the feasibility of secondary canal operation at different discharges. Modifications in outlet dimensions were estimated for better performance. At tertiary level Geographical Information System (GIS) based modeling was used to compute the monthly irrigation durations of different fields and by different users of a tertiary unit. Some data was collected in collaboration with International Water Management Institute and NWFP Irrigation Department. This included discharges of the main canals and design data of the main and secondary canals. Other data was taken through field measurements which included daily discharges of secondary and tertiary canals, verification of the design data of the secondary canals and cropping patterns.

The results indicated that there was over supply to the system. Application of CBIO model achieved 50% water saving in a downstream control irrigation system in the periods of low irrigation demand during March-April and November-December. This was the maximum possible saving under CBIO. Further water saving was found from an additional measure of night closure of secondary canals. The simulation of secondary canals at different discharges indicated that the performance of most of the canals was not satisfactory. Outlets in the head reaches of the canals were overdrawing resulting in under supply to the tail outlets. The actual irrigation duration computed for individual fields and users of a tertiary unit showed that the irrigation times required were highly variable from month to month. In the months of low demand, water supply of only a few hours was required at secondary and tertiary systems as compared to a maximum of 720 hours per month.

Download Full Thesis
8569.07 KB
S. No. Chapter Title of the Chapters Page Size (KB)
1 0 Contents
689.83 KB
2 1 Introduction 1
657.72 KB
  1.1 General 1
  1.2 Main System Of Irrigation 2
  1.3 Tertiary Systems 4
  1.4 Problem Definition 5
  1.5 Main Objectives 8
  1.6 Usefulness Of Research 9
3 2 Measurement / Collection And Analysis Of Data 10
2319.94 KB
  2.1 Introduction 10
  2.2 Description Of The Research Sites 10
  2.3 Measurement / Collection Of Canal Data 14
  2.4 Meteorological Data 17
  2.5 Cropping Patterns 19
  2.6 Map Of The Tertiary Units 24
  2.7 Analysis Of Flows Data 26
  2.8 Analysis Of Operation Of The Upstream Control Main System 34
  2.9 Operation Of The Secondary And Tertiary Canals In Upstream Control System 41
  2.10 Operation Of The Downstream Control Main System 44
  2.11 Conclusions 46
4 3 Crop Based Irrigation Operations ( Cbio )Model 47
511.53 KB
  3.1 Introduction 47
  3.2 Basic Control Of Cbio 48
  3.3 Operation Cycles 51
  3.4 Scheduling Of Water Supplies 52
  3.5 Conclusions 55
5 4 Hydrodynamic Model Canalman 56
1596.82 KB
  4.1 Introduction 56
  4.2 Canalman Model 57
  4.3 Outlet Structures 58
  4.4 Governing Equations 58
  4.5 Trapezoidal Cross-Sections Equations 60
  4.6 Rectangular Gates 62
  4.7 Sharp-Crested Weirs 64
  4.8 Numerical Solution 65
  4.9 Simulation Of Irrigation Canals ( Cis ) 71
  4.10 Comparison Of Canalman And Sic 73
  4.11 Calibration And Validation Of The Model 74
  4.12 Conclusions 84
6 5 Tertiary Rotation Scheduling 87
357.15 KB
  5.1 Introduction 87
  5.2 Gis-Basic Concept 90
  5.3 Irrigation Requirements 91
  5.4 Net Available Discharge At Field Outlet 92
  5.5 Computation Of Required Field Irrigation Duration 92
  5.6 Conclusion 92
7 6 Comparison Of Supply And Demand Under CBIO Operations 93
740.88 KB
  6.1 Introduction 93
  6.2 Demand And Supply Under Cbio Schedules For Downstream Control Canal 94
  6.3 Operation Of The Secondary And Tertiary Canal In Downstream Control System 96
  6.4 Conclusions 107
8 7 Assessment Of Opening And Closing Of Canals At Secondary Level 108
750.52 KB
  7.1 Introduction 108
  7.2 Evaluation Of Possible Secondary Canal Lengths For Opening And Closing 109
  7.3 Opening €“ Closure Of Secondary Canals In Upstream Control System 114
  7.4 Opening And Closure Of Secondary Canals In Downstream Control Systems 116
  7.5 Conclusions 119
9 8 Performance Assessment Of Secondary Canals 121
619.85 KB
  8.1 Introduction 121
  8.2 Operation Scenarios 121
  8.3 Operation At Different Discharges 122
  8.4 Modifications In Outlet Dimensions 127
  8.5 Conclusions 131
10 9 Conclusions 132
161.89 KB
  9.1 Conclusions 134
  9.2 Recommendations 134
11 10 Bibliography 136
292.13 KB
12 11 Annexure 143
60.54 KB