DESIGN OF DRAINAGE AND CLEAN WATER DISTRIBUTION SYSTEM, ABSORPTION TRENCH, AND DEWATERING AT MIXED-USE BUILDING THE TERRACE CIBADAK BANDUNG

• Main Author: Fayd Haekal, Muhammad
• Format: Final Project
• Language: Indonesia
• Online Access: https://digilib.itb.ac.id/gdl/view/50212
• Institution: Institut Teknologi Bandung

The Terrace is a mixed-use building that functioned as commercial and residential purpose. This building is located at Cibadak culinary arcade, Astanaanyar district, Bandung, West Java. Due to located in densely populated area, The Terrace needs a drainage system that can withhold itself from the flood. The drainage system is designed by adapting the eco-drainage concept, which consist of designing drainage channel, clean water distribution system, and rain water absorption system, while also abiding to the Zero Delta Q policy. This concept makes a part of rain water that falls into the specific area of The Terrace flows into a water storage for reuse, while the rest part is going to be absorbed into the deep groundwater. Apart from drainage system, inspection for flood elevation and dewatering design is also needed, so the ground elevation could be raised and the groundwater will not obstruct The Terrace construction. The potential of flooding analyzed by the Snyder’s synthetic unit of hydrograph shows that increasing of flood level is not necessary. Drainage system is designed using the rational method with 5-year return period of Gumbel frequency method. The designed drainage channel has a square cross section with the width varies from 10 cm to 35 cm and depth varies from 10 cm to 60 cm. The clean water distribution system is designed to meet the daily water demand of The Terrace. Rain water that falls over The Terrace is channeled into filtration tank to be filtered and collected into the water storage together with the water supplied by PDAM. The water storage has capacity of 444 m3 and the wall is made of reinforcement concrete. Some of rain water that falls to the ground flows into absorption trench with a width of 40 cm, a depth of 30 cm, and length 12.5 m and 24 m. Dewatering is done by open pumping method during excavation and deepwell method after excavation. The dewatering discharge from seepage during excavation is 544 litres/minute while the discharge after excavation is 176 litres/minute. The discharge from rain water that falls into excavation area is 2228 litres/minute.