PENAKSIRAN RISIKO BANJIR LAHAR DI DAERAH ALIRAN SUNGAI (DAS) GENDOL DAN DAS OPAK, YOGYAKARTA

• المؤلفون الرئيسيون: , PUTU PERDANA KUSUMA WIGUNA, , Dr. M. Aris Marfai, M.Sc
• التنسيق: Theses and Dissertations NonPeerReviewed
• منشور في: [Yogyakarta] : Universitas Gadjah Mada 2012
• الموضوعات: ETD
• الوصول للمادة أونلاين: https://repository.ugm.ac.id/99292/; http://etd.ugm.ac.id/index.php?mod=penelitian_detail&sub=PenelitianDetail&act=view&typ=html&buku_id=54882

extinct. However, the secondary hazard still expected to occur. The secondary hazard is lahar flood, which triggered by heavy rainfall in the upper slope of Merapi Volcano. The aim of this research is, to assess the risk of lahar flood to the population in Gendol and Opak watershed using three parameters of risk, hazard, vulnerability, and coping capacity. Two scenarios are used in predicting the hazard area, with lahar volume and lahar discharge scenario. The most extensive area which impacted by lahar flood in Gendol watershed, based on lahar volume scenario is 1562,26 ha compares to 1240,14 ha in Opak Watershed. Meanwhile, hazard assessment using lahar discharge scenario, total amount of 985.98 ha area of Gendol watershed are effected by lahar, compares to 625,85 ha in Opak Watershed. Total of 16 dusun (village/ rustic) in Gendol watershed are affected by the highest lahar volume scenario of 40 million m 3 , compares to 15 village in Opak Watershed. Based on lahar discharge scenario, Village of Glagahmalang, Ngancar, Koripan and Pencar in Gendol watershed experience the largest effect of more than 30 ha. Meanwhile in Opak Watershed, only Gondang Village has experience more than 30 ha of affected area. Inhabitants of Dusun in Gendol watershed are more vulnerable to lahar flood. 6 villages in Gendol watershed has high until very high level of vulnerability, compares to 5 Villages in Opak watershed. But, the inhabitants of Villages in Opak Watershed have higher coping capacity. It proves by the number of villages with high until very high class of coping capacity, 19 villages in Gendol watershed and 25 in Opak watershed. The differences in hazard level, vulnerability and coping capacity between to watersheds, bring differences in total affected inhabitants with high until very high risk. Based on lahar volume scenario, total of 10924 inhabitants has risk to lahar flood in Gendol watershed, compares to 7601 inhabitants in Opak watershed. Based on lahar discharge scenario, total 9991 inhabitants have risk to lahar flood in Gendol watershed, compares to only 504 inhabitants in Opak watershed.