Analysis of the Increasing Need of Drinking Water as the Effect of High-rise Building Growth in Eastern Surabaya

Surabaya City, the capital of East Java, is one of the centers for business, trade, industries, and education in Indonesia. Surabaya is also a very important hub for the eastern part of Indonesia, making it a strategic location for property investors. Nowadays, Surabaya's economic is hugely affected by its significant growth in properties, where skyscrapers, malls, plazas, apartments, office buildings, and hotels will continue to be built in the coming years. The amount of the aforementioned commercial buildings creates concern on drinking water supply management. In this study, the projection of drinking water need was determined by projecting inhabitants or users of high-rise buildings based on existing project data as well as interviews and field survey to people in charge. The study was directed towards 9 high-rise buildings in the eastern part of Surabaya, in particular in the districts of Gubeng, Tenggilis Mejoyo, Rungkut, and Gunung Anyar. The projection data were then analyzed and modeled using WaterCAD. Technical aspects discussed in this study include the amount of water, the network of water distribution system, and supply management. This study found that the total water need would range between 3-20 L/s depending on the number of inhabitants or user. The modelling predicted year to year situation on flows and pressures until 2025. In the last year of the modelling, the pressure obtained on the distribution system were in the range of -4 to 18 mH2O, which is a critical range of pressure in those areas.