LANDSLIDE RISK MAPPING ALONG RANTEPAO – PALOPO ROAD SECTION, SOUTH SULAWESI PROVINCE
Abstract: Rantepao – Palopo
Road Section is 61 km long, which provides a connection between Palopo City and
North Toraja District. Geographically, the road is winding, located in a hilly
area with steep canyon. This condition makes the road vulnerable to soil
movement or landslide. On 8 November 2009, a landslide, which caused a huge
material and immaterial loss, took place. The scale of the disaster was so
large that it was classified as a national disaster. In the landslide disaster
management, the mitigation and preparedness effort will be more focused if
complemented with spatial data in the form of landslide hazard map in Rantepao
– Palopo road section. This research uses Public Works Minister Regulation
No.22/PRT/M/2007 concerning landslide hazard area spatial planning as the
reference which is modified and assisted with the application of Geographical
Information System (GIS). Based on the hydro-morphology condition, the research
location can be classified into three, namely typology A (> 1000 mdpl),
typology B (500 – 1000 mdpl), and typology C (<500 mdpl). Each typology
consists of natural physical aspects with slope indicator, soil type, geology,
rainfall, distance from the river/slope water system, distance from seismic
fault and vegetation. Human activity aspects comprise planting pattern
indicator, slope cutting, pond, population density, and mitigation effort.
Based on the regulation, several indicators are difficult to apply in the road
section study. Therefore, in this research, some modifications are made to
several indicators. In the slope cutting indicator, to obtain slope cutting
map, overlay process on topography map, slope variation map, and road section
map was performed. The distance from the river/slope water system was obtained
by calculating the distance from the river to the road, the closer the river to
the road, the bigger the vulnerability. Meanwhile, the distance from the fault
was evaluated based on the existence of seismic faults in the research
location. Landslide hazard map was obtained by applying overlay process to
natural physical aspects map and human activity map. To obtain a hazard map for
Rantepao – Palopo road section, a modification by applying overlay to road
section map and landslide hazard map was performed. Hazard map on Ranteo-Palopo
is divided into three types, i.e. low risk, medium risk, and high risk.
Author: Dian Pratiwi
Anggeraini
Journal Code: jptsipilgg150051