Rain Garden Model for Stormwater Management in Sentul City, Bogor, Indonesia

Abstract

Developing area is a multidimensional process and often has minimum attention in water management aspect. Sentul City is an example of an area in Bogor Regency that is growing rapidly but has problems in water management. The limitation of raw water is caused by the lack of groundwater and frequent disruption in the water distribution system. This causes the raw water supply depends on the Local Water Company of Bogor Regency. In fact, Sentul City has the potential to conduct independent raw water from its high rainfall. Therefore, rainwater harvesting is needed through stormwater management, one of its application is by the rain garden. The objective of this paper is to present the research result of the rain garden model recommendation that is suitable to be applied in Sentul City. The used methods are mapping the existing site conditions, analysis of the rain garden suitability, calculate the rain garden dimensions, and modeling the rain garden. This study conducted in Lake Indah, Lake Teratai, Siliwangi Street, M.H Thamrin Street, and Plaza Niaga 1. The rain garden analysis and dimensions are affected by the soil, topography, catchment area, and runoff volume of the site. The required rain garden surface area is 171.50 m2 at Lake Indah, 312.48 m2 at Lake Teratai, 6,449.88 m2 at Siliwangi Street, 6,573.01 m2 at M.H Thamrin Street, and 896,51 m2 at Plaza Niaga 1, while the required rain garden depths are 15-30 cm and 45-60 cm. The rain garden model is designed based on the form, inflow and outflow design, planting media, and plant aspects. Thus, the results of rain garden models are different according to the conditions of each site.