Author: Tolentino B. Moya

Year: April 2018 Special Issue
Volume: 28 No. 1
Pages: 102–120

Abstract:

Irrigation is a socio-technical infrastructure for food and water security programs of many developing countries, including the Philippines. Consequently, the government has been heavily investing in irrigation development to boost crop yield and to enlarge currently irrigated areas for many years now. However, the Philippine climate has been changing; and the climatic variations and change present potential threats to the resilience of the Philippine irrigation systems. The impacts of climate variability and change on the resiliency of irrigation infrastructures challenge the sustainability of the government’s investments in food security programs. Climate change would alter the Philippine water cycle thus changing the temporal and geographical patterns of rainfall, evapotranspiration, runoff, and groundwater recharge. Extreme hydro-meteorological events have been occurring more frequently in the country today—strong typhoons with undocumented wind speed and with rainfall of unrecorded amount and intensity are being experienced more often now than before. These extreme events bring about risks to irrigated agriculture because of the uncertainty of either too much or too little water, or both. The aforementioned risks will infringe upon the planning, design, and construction processes of new irrigation systems, and upon the operation and maintenance of existing ones. The study applied systems dynamics approach to review and analyze factors that strengthen or weaken the resiliency of the Philippine irrigation systems to the impacts of climate variability and change. The intrinsic system resilience to stresses and episodic shocks of climate variability and change emerge from the interrelationship and feedback interaction between the elements and irrigation processes in an irrigation system. The current internal dynamics in most irrigation systems exposes its incapacity to serve fully its designed area. As a result, the overoptimistic technical and economic assumptions used in the planning and design phase imperiled the intrinsic resilience of existing irrigation systems to climate variability and change. Moreover, the degradation of physical infrastructures attributable to low maintenance level and inadequate rehabilitation works result in continuing inability of irrigation systems to serve the designed area with adequate water and weaken their intrinsic resilience. The social components of the system–the irrigation agency, and the farmer community in particular, are undertaking varied adaptation actions to increase and strengthen both the system’s “soft” and “hard” resiliency.