Determination risk of liquifaction disaster based on spatial distribution unconfined aquifer at the Tindaki Groundwater Basin, Parigi Moutong District

Abstract

Natural disasters such as earthquake, tsunami and liquefaction in Central Sulawesi Province in 2018 had a significant impact on economic growth. This demands disaster risk reduction, especially liquefaction disasters. This research was conducted in Tindaki Groundwater Basin, Parigi Moutong Regency, especially in Parigi sub-district, which includes: Lebo, Bambalemo, Kampal, Maesa, Bantaya, and Olaya. The purpose of this study was to determine the level of risk of liquefaction based on the spatial distribution of the unconfined aquifer in Tindaki Groundwater Basin. The number of samples is 100 points taken randomly, consisting of community dug wells to obtain phreatic depth. The technique of collecting data is random and proportional sampling.The method used in this study is geological and hydrogeological approaches with rock formation as a determining parameter for groundwater density. The results showed that the average depth of the phreatic level was <10 meters from the ground and was in the alluvium formation. Based on the results of the study, it can be concluded that the potential for liquefaction in the research area is in the medium to high potency.