Abstract
The route of Tomohon-Manado almost every year in the rainy season, landslides occur, because it is supported by the physical condition of the land with a rough topography that appears from the steep slope, the building material is Lokon volcano material which is classified as young gungungapi so the material is not compact and vulnerable to landslides. In addition to the physical condition of the land, the Tomohon-Manado route is the main transportation route that connects Manado as the capital of North Sulawesi Province and several Regency Cities such as Minahasa Regency, South Minahasa Regency, South east Minahasa Regency and even to Bolaang Mongondow Regency. On the other side of the Tomohon-Manado route also takes place the economic activities of the population such as fruit trade, restaurants and there are also lodging which strongly supports the economy of more specialized residents who live on the Tomohon-Manado Line. In this regard, it is very important to study the problem of landslides in the Tomohon - Manado route with the following problem formulation: What are the conditions of landslides in the Tomohon-Manado route. The purpose of this study is to examine the condition of landslides in the Tomohon - Manado route. The method used includes the interpretation and analysis of photographs / images, field observations and measurements, laboratory analysis and the value of terrain parameters to determine the level of landslide hazards. The results showed based on the value of the terrain parameters, the landslide hazard in the Tomohon-Manado route was subject to three levels of landslide hazards in the Tomohon-Manado river, which were subjected to low, medium and high hazard levels. Landslide events were found both on slopes to steep slopes, types of landslides in the Tomohon-Manado route include slide and slope types and after the 2014 flash flood event in Manado, landslide conditions in the Tomohon-Manado route experienced an increase in the number of landslides and the amount of material that moved and had an impact for the closure of the Tomohon - Manado route in quite a long time and the existence of fatalities and damage to housing in the Tomohon - Manado route.
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