Inundation in Kaligawe street affected by heavy rainfall, lack of maintenance on
drainage system, sea-level rising, and land subsidence. For the simulation of longterm
inundation
in
Semarang,
most
study
focused
on impact
of
sea-level
rising
and

land
subsidence

to inundation height. This observation aims to investigates main
factor that cause inundation along Kaligawe street Semarang and impact of sealevel

rising and land subsidence to height of inundation. One-dimensional HECRAS
simulation

used as a method to carry out height of inundation. Simulation
conducted on existing condition, longest period of inundation, and 2, 5, 10, 25 years
forecasting under 3 scenarios. Existing condition compared to canal capacity along
Kaligawe street to observe inundation factor that come from drainage system.
Furthermore, simulation on 2, 5, 10, 25 years forecasting under rainfall, sea-level
rising, and land subsidence scenarios carried out to find out factor that influence
inundation the most. The result indicates that canal along Kaligawe street did not
adequate to accommodate inundation discharge. Furthermore, sea-level rising has
no impact to height of inundation along Kaligawe street. However, land subsidence
contributes 0.98-meter inundation for next 25 years. Thus, small capacity of canal
become the major factor that causing inundation along Kaligawe street Semarang.