Analysis of Rainfall Characteristicsfor Flood Estimation in Way Awi Watershed
Abstract: This study
investigates rainfall intensity distribution in Way Awi watershed located in
Bandar Lampung, and how their impacts on flood peak and flood hydrographs.
Hourly rainfall data is examined to obtain design rainfall intensity and
rainfall intensity distribution at rainfall duration from three to eight hours.
Rainfall-runoff model, i.e. Rational method is used to calculate flood peak
while unit hydrograph method is used to develop flood hydrograph. This study
shows that in Way Awi watershed 88.3% to 96.4% of 24-hour rain occurs in three
to eight hour durations. In addition, rainfall with three hour duration
generates the highest flood peak, followed by four hour duration rainfall. When
rainfall duration and design rainfall intensity are the same but rainfall
intensity distribution is different, generated flood hydrograph may have
different flood peak magnitude and timing. Result of this study is useful for
flood analysis and mitigation in Way Awi watershed.
Author: Kusumastuti D.I.,
Jokowinarno D., van Rafi’i C.H., Yuniarti F
Journal Code: jptsipilgg160005
