Methodology for risk analysis of irrigation structures

During their operational life, irrigation structures are exposed to damage resulting from floods, earthquakes or just wrong management Some failures may result in accidents that may pollute irrigation water sources. Thus, risk analysis must be part of the design and evaluation of irrigation structures. This paper presents a methodology for risk analysis that integrates two different techniques: Event tree analysis for the study of the system and the use of fuzzy numbers for the management of uncertainty. The combination of both techniques produces a simple methodology that can be used as a complement for the design or evaluation of irrigation structures and systems. The risk analysis of a chemi-irrigation system after a failure of the pumping system is used to illustrate the methodology here presented. The analysis shows that the retention valve plays a very important role to prevent chemical spills into the water source. An additional example presents seismic risk analysis of an irrigation channel after being hit by an earthquake grade VIII in Mercalli's scale.