Consideration of costs and factors of safety for landslide mitigation of the housing infrastructure in Sawahlunto

Abstract

The Indonesian government, through the Ministry of Public Works and Public Housing, is conducting a housing infrastructure development to encourage economic growth and improve the quality of Indonesian human life. However, the limitations of proper land in the implementations have resulted in the compulsion to build public houses in disadvantaged areas. On November 2, 2018 there was a landslide in a public residential area in the city of Sawahlunto which resulted in 4 houses which are unable to function anymore and 12 others which are damaged and uncomfortable to occupy. In order to investigate the landslide, the field survey has been carried out and the soil samples have been taken and tested in the laboratory. Then, some remedial methods of landslide remedial work at that location were carried out. Furthermore, a number of possible methods are compared in terms of the value of safety against landslides and the cost of the countermeasures. The main criterion is the costs needed for disaster mitigation for this local landslide, which must be smaller than the value of the affected area. If the cost for disaster mitigation is greater than the value of the affected area, then the relocation option may be a wiser choice. However, in this study, the stone masonry is the right choice to be used in the remedial action.