The eighth National Economic and Social
Development Plan (1992-1996) called for
achievement of water resource sustainability
(NESDB 1992). The plan describes development
issues and problems with the guidelines for
developing water resources. Meteorological Drought
risk area is a result of a variety of factors. Drought
generally originates from less precipitation over an
extended period of time. These include occurrence of
the lack of the rain in the rainy season, number and
amount of rainfall and other climatic anomalies.
Palmer (1965) identified monthly index values for
past dry periods to yield an equation for calculating
drought severity in four classes. In an operational
definition of drought it identifies drought from
impact data (i.e. crop damage). It is widely accepted
that combination of physical nature of area, amount
of rainfall and water resource development leads to
identify the drought pattern.