Abstract:
In the study case, Jababeka II Industrial Estate has an annual flood
problem since 2014 [35]. As for the indicate the cause of the problem,
this research was conduct to analyze the existing condition and knowing
the water balances in Jababeka II Industrial Estate using SWMM
software. Since learning the study area's current situation, many
solutions came up to decrease flood. But based on the previous research
that recommends applying cistern for each tenant industry, this study
using SWMM wants to know the effectiveness of flood reduction using
Low Impact Development (LID) control. The type of LID that is used
is rain barrel. In conducting the study, the method used a quantitative
method and used secondary data for the data collection method. These
data refer to data collected from the WTP Jababeka Residential,
drainage dimension, and Jababeka II master plan from the existing
drainage system with precipitation events in 12 years (2009-2020).
Other than that, Google Maps observation was used to obtain an
impermeable area. Because using LID control, divided into two
impervious regions, all waterproof categories are first and second
impermeable treated areas. Precipitation data used for hydrological
analysis is on the city classification to get the amount of rainfall planned
for the five-year return period. The probability distribution uses Log-
Pearson III with a planned rain of 128.22 mm/d and the highest intensity
of 54 mm. Due to the simulation result it was found that seven-channel
is not from the industry area as a temporary area, affecting the industry's
discharge channel capacity. Thus, floods occurred in many points of
drainage caused by the limited green surface area. It shows that water
imbalance occurred, which between inflow and outflow of Jababeka II
is not equal with a surface-continuity result of -0.151%. Meanwhile,
using the same planned rainfall and intensity, the simulation results
using LID control show an increase in the likelihood of flooding, with
as many as 25 subcatchments using LID control based on a building
area of more than 10,000 m2. So, it can be concluded that based on the
simulation results of the existing conditions, the amount of water
entering Jababeka II is not the same as the amount of water that comes
out. It causes flooding in several locations. And the simulation results
using LID, which in this study served as an alternative solution, namely
the use of rain barrels in several industries, showed less effective in
reducing the possibility of flooding. Therefore, the recommended
change of the dimensions according to water storage is that the
reduction in the case of flooding can be optimized.
