ABSTRACT
The objective of this study is to develop a Drought Early Warning Model of Tsengwen - Wusanto Reservoir in Taiwan using the Standardized Precipitation Index (SPI) and Standardized Reservoir supply Index (SRSI) along with Drought Early Warning Indices indicated by Linear Discriminant Analysis. Tsengwen is a very important reservoir to the agricultural sector of Taiwan. In the past, Drought event in the Tsengwen River Basin used to occur frequently and as a matter of fact the Tsengwen does not have the complete drought water warning system to respond directly when the water condition changed rapidly. For this reason, the researchers has have expressed their interested in studying and recording data of the Tsengwen reservoir. Based on the two drought indexes, there are SPI3, a Meteorological Drought Index and SRSI3, Hydrological Drought Index. In future SPI1 and SPI3 will be used working with LDA to develop drought early warning model in this area in for 1 month and 3 months respectively. The results show that the duration of a drought event with the regime light in 2009 and 2010 that selected year for predicting the drought events, 50% predicted right in 2009 and 67% right in 2010 for 1 month ahead prediction. In 3 months ahead prediction the result show with 58% right in 2009 and 67% right in 2010. Drought event in a dry season and wet season also show the value and the different duration affected.

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