Role of Reservoir Operation in Sustainable Water Supply to Subak Irrigation Schemes in Yeh Ho River Basin : Development of Subak Irrigation Schemes: Learning From Experiences of Ancient Subak Schemes for Participatory Irrigation System Management in Bali

Quantitative research with respect to the combination of engineering and socialcultural- religious aspects based on the __Tri Hita Karana__ philosophy in Subak irrigation schemes is original in the field of land and water development. A scenario analysis needs a good and careful system approach. Based on a Generic Algorithm the RIBASIM model was applied using the dependable 80% of discharge and shifting the start of land preparation. The results provide evidence that the cropping pattern of the fifth scenario results in an overall optimal agriculture production of the Subak schemes. The recoverable flow considered in the river basin scheme model plays an important role in the optimisation. Nevertheless, if a normal hydro-climate occurs, the other scenarios, especially the first scenario, can be applied as well. When the indigenous knowledge of farmers is compromised with present day knowledge of agricultural and technological developments, capability of these farmers increases, thus reflects the applicability of the __Tri Hita Karana__ philosophy on harmony among people and harmony among people and nature. 6.1 Model categorization -- 6.2 Modelling of Subak schemes related to Tri Hita Karana philosophy -- 6.3 Multiple purpose reservoir operation -- 6.4 Scenario analysis in Subak schemes -- 6.5 Simulations with the RIBASIM model -- 6.6 Application aspects of the RIBASIM model -- 6.7 Yeh Ho River system as input in the RIBASIM model -- Chapter 7 Scenario analysis -- 7.1 Hydrologic and hydraulic analysis -- 7.1.1 Analysis of rainfall data: dependable rainfall and effective rainfall -- 7.1.2 Streamflow analysis -- 7.1.3 Potential evapotranspiration -- 7.1.4 Reservoir water surface losses and gains -- 7.1.5 Other reservoir losses and gains -- 7.1.6 Reservoir elevation/storage/area relationship -- 7.1.7 Flow routing in the reservoir and hydraulic profile of outlets -- 7.1.8 Evaluation of reservoir lifetime based on sedimentation -- 7.2 Advanced irrigation node in RIBASIM -- 7.2.1 Schematization of the irrigated area -- 7.2.2 Interactive graphical cropping plan editor -- 7.2.3 Simulation of a cropping plan -- 7.2.4 Soil moisture characteristics -- 7.2.5 Crop water requirement in a paddy terraces block -- 7.2.6 Computation of command area water demand, actual field water balance and effective irrigation water supply -- 7.3 Results of economic evaluation of storage allocation -- 7.3.1 Pricing of paddy productivity -- 7.3.2 Pricing of domestic water -- 7.4 Scenario analysis, simulation and optimisation of Yeh Ho River Basin -- 7.4.1 Simulation of the first scenario -- 7.4.2 Simulation of the second scenario -- 7.4.3 Simulation of the third scenario -- 7.4.4 Simulation of the fourth scenario -- 7.4.5 Simulation of the fifth scenario -- 7.5 Summary of the simulation and optimisation of Yeh Ho River Basin -- 7.5.1 Utilisation of hydraulic structures -- 7.5.2 Verification of the model -- Chapter 8 Evaluation Cover -- Half Title -- Thesis committee -- Title -- Copyright -- Table of contents -- Acknowledgements -- Chapter 1 Introduction -- Chapter 2 Background and objectives -- 2.1 Profile of the region -- 2.2 Water resources -- 2.2.1 World water resources -- 2.2.2 Water resources in Indonesia -- 2.2.3 Water management in Indonesia -- 2.2.4 Water resources in Bali -- 2.3 Definition of Subak irrigation schemes -- 2.4 Subak schemes -- 2.4.1 Paddy terraces -- 2.4.2 Subak irrigation system -- 2.5 Subak cultivation area -- 2.6 Previous studies on water management of Subak irrigation schemes -- 2.7 Problem description -- 2.8 Objectives -- 2.8.1 Research questions -- 2.8.2 Hypotheses -- 2.8.3 Research objectives -- Chapter 3 Development of Subak irrigation schemes: learning from experiences of ancient Subak schemes for participatory irrigation system management in Bali -- 3.1 Introduction -- 3.2 Method and discussion -- 3.2.1 PIM in irrigation system operation and maintenance -- 3.2.2 PIM with respect to socio-culture and economics of agriculture -- 3.2.3 PIM in light of a religious community -- 3.3 Result and conclusion -- Chapter 4 Subak in the south of Bali: discharge analysis for a system approach to river basin development with Subak irrigation schemes as a culture heritage -- 4.1 Introduction -- 4.2 Study of a river basin -- 4.3 Managed flow approach in Yeh Ho River Basin -- 4.4 Method and material -- 4.5 Results and discussion -- 4.6 Conclusion -- Chapter 5 Hydrology and hydraulic approaches: irrigation-drainage of Subak irrigation schemes, a farmer's perspective over a thousand years -- 5.1 Introduction -- 5.2 Methodology -- 5.2.1 Observation of the water balance in a paddy terraces block -- 5.3 Results and discussion -- 5.4 Conclusion -- Chapter 6 Model simulations and optimisation technique "A Subak irrigation scheme, primarily in Bali, Indonesia concerns an irrigation system of which the construction, operation and management are based on agreed principles of technology, management of agriculture and religious community. Subak systems have been well known since the 9th Century. As a manifestation of the Cultural Landscape of Bali Province the Subak schemes are since June, 2012 included in the World Heritage List of UNESCO. These systems are managed by a Subak Association based on the Tri Hita Karana philosophy - harmony between human beings and God, harmony between people and nature, and harmony between people and people. The problem of insufficient water in the dry season developed in the Yeh Ho River Basin. Because of this the main objective of this study was to develop an optimal reservoir operation strategy in relation to the water supply of the Subak irrigation schemes, capable to support agricultural productivity at upstream, midstream and downstream level. Based on a Generic Algorithm the RIBASIM model was applied using the dependable 80% of discharge and shifting the start of land preparation. The results provide evidence that the cropping pattern of the fifth scenario results in an overall optimal agriculture production of the Subak schemes. The recoverable flow considered in the river basin scheme model plays an important role in the optimisation. Nevertheless, if a normal hydro-climate occurs, the other scenarios, especially the first scenario, can be applied as well. This reflects the applicability of the Tri Hita Karana philosophy on harmony among people and harmony among people and nature."--Provided by publisher 8.1 Recommendations for river basin development -- 8.1.1 Telaga Tunjung Reservoir operation based on Subak cropping patterns -- 8.1.2 Operation and maintenance of the Subak irrigation systems -- 9 References -- APPENDICES -- Annex A. Abbreviations -- Annex B. Symbols -- Annex C. Surface runoff analysis as inflow to the Telaga Tunjung Reservoir -- Annex D. Analysis of rainfall data -- Annex E. Reference evapotranspiration -- Annex F. Hydraulic profile of outlets -- Annex G. Reservoir and its hydraulic structures -- Annex H. Information on reservoir sedimentation -- Annex I. Infiltration and percolation -- Annex J. Results of the measurements in a paddy terraces block -- Annex K. Graphs of scenario simulations with RIBASIM -- Annex L. Summary -- Annex M. Samenvatting -- Annex N. About the author