Utilization of WEAP Software to Assess Current and Future Water Demand of Karachi City

Abstract

The availability of fresh water in the required quantity is the major challenge in Karachi city. There is a need to evaluate the potential of available water resources and devise a suitable distribution mechanism for the city. This study aims to determine the current water situation of Karachi City and it predicts the future water situation till 2040 considering 30 gallons per capita per day (GPCD) as an annual requirement per person. The study is conducted with the help of WEAP software. WEAP software uses different scenarios to estimate future water needs. In the software, water needs of Karachi from 2020 to 2040 were assessed and analysis of water demand, unmet demand, supply delivered, and demand site coverage was carried out. During modeling, a growth rate of 2.31% per year was used. The result indicates that the water demand will increase to 759.064 million gallons per day (MGD) in 2040, so an extra supply of 336.564 MGD will be required to meet water demands and urbanization of the city. To meet this unmet demand, it is suggested that water leakage be reduced as proposed by the Karachi Water & Sewerage Board (KWSB). Moreover, water conservation techniques and the use of treated wastewater along with the existing water are recommended to reduce the unmet demand.