Drainage is one of the basic facilities that was designed as a sewer system
to fill society needs and it is an important component in urban planning
(especially infrastructure planning). The drainage system is an aspect that cannot
be separated from the planning of civil construction buildings. At the Permata
Harmoni Housing area if the rain happened the drainage capacity is unable to
accommodate rainwater runoff so that it creates a pool that disrupts residential
activities. This study aims to analyze drainage capacity with a rational method in
Permata Harmoni Housing. The data used is rainfall data from Arca station.
Based on the results of hydraulic analysis, it shows that there are 4 channels that
do not meet capacity. The channel are, Perum Raya with existing Q size = 0.0067
m3/sec and Q Plan = 0.0099 m3/sec; Existing A5 Q block = 0.0007 m3/sec and Q
Plan = 0.0010 m3/sec; Existing C1 and C2 Q = 0.0013 m3/sec and Q Plan 0.0027
m3/sec; Existing C2 and C4 Q complex = 0,0008 m3/sec and Q Plan = 0,0018
m3/sec.