Assessment of water scarcity index – related drought index for urban and sub urban area / Raja Muhammad Naufal Raja Azman

The climate change interference and increase of surface temperature have contributed to the changes at the atmosphere that give a significant effect to the availability of water. Malaysia is one of the countries which effected with this event and had been suffered series of drought events in 1997, 1998, and 2014. These problems contribute to the disruption of country’s economic development and quality of life. The using of drought indices for analytical is important and it can estimate the drought affect that are being experienced accurately. The main objective of this study is to assess the relationship between drought index and water scarcity for water security Malaysia. The data for this study was obtained from Malaysian Meteorological Department (Met Malaysia) and Department of Irrigation and Drainage (DID) in order to determine the drought index and water scarcity index. Then, the drought index was determined using The Standard Precipitation Evapotranspiration Index (SPEI) for urban and suburban and the analysis was conducted using R Studio software. The selection of SPEI was due to the availability of data. Meanwhile, the water scarcity index was calculated using Water Exploitation Index Plus (WEI+) according to the formula for urban area. The findings of this study were indicated that the frequency of drought index for Pahang River basin are 26 for SPEI-3, 23 for SPEI-6, and 22 for SPEI-12. Meanwhile, the frequency of drought index for Langat River basin are 54 for SPEI-3, 58 for SPEI-6, and 61 for SPEI12. As for water scarcity index for Langat River basin was determined in year 2015 until 2018. The value of water scarcity index for Langat River basin are 2.60E-03 in 2015, 3.81E-03 in 2016, 3.39E-03 in 2017, and 3.68E-03 in 2018. In order to assess the relationship between both index for Langat River basin, the Artificial Neural Network and Microsoft Excel is being used and by using Microsoft Excel indicate a strong positive relationship with the value of correlation coefficient, R are 0.9512 for SPEI-3, 0.9735 for SPEI-6, and 0.9756 for SPEI-12. Meanwhile, by using ANN, indicated the strong positive relationship with the value of correlation coefficient, R of 0.9677 for SPEI-3, 0.9545 for SPEI-6, and 0.9633 for SPEI-12. Thus, both tool shows the positive result for the relationship between SPEI and WEI+. From the result of SPEI versus WEI+, it can be concluded that when the higher value of severity index for SPEI, the higher value of WEI+ will be obtained. From that analysis, the recommendation and propose the mitigation can be provided to the related organization to take an action in planning and managing the water supply and to prevent the serious impact on the agricultural as well.