On average the Peninsular Malaysia receives 324 billion of rainwater annually, where as the current demand is about 11 billion only [1]. The demand in the year 2050 could be about 18 billion m. As such, it is understood that the availability of raw water in the country, generally, is not an issue. The problem is due to the fact that rainfall is not uniformly distributed over the year temporally and spatially; baseflow is reduced due to urbanisation, supply is less than the demand in the city centres, distribution network is not adequate to transfer water from the low demand to the high demand areas, water get polluted and rendered less suitable for the intakes when passing through the urban centres.