1st Edition
Modernisation Strategy for National Irrigation Systems in the Philippines Balanac and Sta. Maria River Irrigation Systems
The book presents documentary evidence of the insufficiency of rehabilitation works to close the gap between the irrigation service and actual area irrigated of publicly funded national irrigation systems in the Philippines. It outlines a methodology for formulating a modernisation plan for national irrigation systems with focus on the mostly ungauged, medium to small canal irrigation systems. The proposed methodology adaptively modified some known modernisation concepts and techniques and integrated them in a more holistic framework in the context of changing weather patterns and river flow regimes. It includes in-depth review of rehabilitation works; system diagnosis; revalidation of design assumptions on percolation and water supply; characterisation of system management, irrigation service and demand; and drawing up of options and a vision for the modernised irrigation systems. Central to the proposed modernisation strategy is the logical coherence among the design of physical structures, system operation and water supply so that improvements of irrigation service are possible. The book discusses the development of the proposed methodology and demonstrates its utility in two case study irrigation systems.
1. Introduction
1.1 General
1.2 Structure of the thesis
2. Background and objectives
2.1 Irrigation in global perspective
2.2 Irrigation in the Philippines
2.3 Description of the research problem
2.4 Research questions
2.5 Research hypothesis
2.6 Research objectives
2.7 General research methodology
3. Description of the Philippines and irrigation systems of the case study
3.1 Brief hydro-geographic description and general climatic conditions
3.2 Economy and agriculture
3.3 Water and land resources utilization for irrigation
3.4 Description of irrigation systems of the case study
4. Issues and concepts on design and performance of irrigation systems
4.1 Historical perspective on the causes of and solutions to poor irrigation performance
4.2 Design issues
4.3 Concepts on irrigation design
5. Assessment of irrigation systems
5.1 Approaches to analyze the hydraulic behaviour of irrigation systems
5.2 Overview of the performance assessment of irrigation systems
5.3 General framework for assessing irrigation performance
5.4 Conclusion
6.1 Overview on rehabilitation
6.2 General methodology
6.3 Definition of terminologies
6.4 Magnitude and impacts of rehabilitation or improvement projects
6.5 Planning and implementation process of rehabilitation projects
6.6 Nature and impact of rehabilitation: a system level study
6.7 Conclusion
7 Diagnostic asessment of the irrigation system design and performance
7.1 Introduction
7.2 Assessment methodology
7.3 Assessment of the consistency among the design philosophy, operational objectives and physical structure of the irrigation system
7.4 Initial rapid system diagnosis and performance assessment through RAP
7.5 Assessing system capacity and functionality
7.6 Sensitivity analysis
7.7 Origins and causes of perturbations
7.8 Conclusions
8. Revalidation of design assumptions on percolation and water supply
8.1 Introduction
8.2 Research methodology
8.3 Field measurements of percolation and farm ditch losses
8.4 Estimates of crop water requirements and irrigation requirements
8.5 Assessment of the reliability of the estimates on available water supply
8.6 Prospects of technical assessment of dependable water supply
8.7 Conclusion
9 Characterization of the system management, services and demand to identify modernisation potentials
9.1 Introduction
9.2 General research methodology
9.3 The management unit and water distribution
9.4 Mapping the services and demand
9.5 Field investigation of potentials for conjunctive use
9.6 Conclusions
10 Options and vision for irrigation system modernisation plan
10.1 Introduction
10.2 General methodology
10.3 Modernisation options for Balanac RIS
10.4 Modernisation options for Sta. Maria RIS
10.5 Visions for system modernisation
10.6 Development of a modernisation plan for NIS
10.7 Conclusion
11 Evaluation
11.1 Introduction
11.2 Key findings
11.3 Strategy to formulate a NIS modernisation plan
11.4 Challenges
11.5 Recomendations
11.6 Future activities
11.7 Conclusion
12 References
Annexes
A. List of symbols
B. Acronyms
C. Major rehabilitation and improvement projects
D. Rehabilitation/improvement cost by component (PhP, x103)
E1. Locations of direct offtakes and drainage inlet along the main canal of Balanac RIS
E2. Locations of direct offtakes and drainage inlet along the main canal of Sta. Maria RIS
G. Water estimation techniques used in the sample NIS
H. List of streamflow gauging stations in Region IV-A
I. Assessment of relative quality of water deliver service and demand for canal operation
J. The drainage network in the service area of Sta. Maria RIS
K. Front line O&M expenses of Balanac RIS and Sta. Maria RIS (PhP 103)
L. Groundwater map of Laguna
M. Well drilling in Sta. Maria RIS service area
N. Vision for the case study systems
O. Summary
P. Samenvatting
Q. About the author
Biography
Mona Liza Delos Reyes is a licensed agricultural engineer with specialisation in irrigation engineering. She holds a senior university researcher position at the University of the Philippines and has more than 15 years experience in development and implementation of irrigation-related applied research, projects and action programs. She has worked as projects leader, irrigation specialist, consultant in a number of irrigation studies, projects and programs funded by the Philippine government and international financial institutions.
