Zonasi Risiko Bencan Banjir di Daerah Aliran Sungai Welang Kecamatan Kraton

Bilqis, Zaqiyyah Salsabila (2018) Zonasi Risiko Bencan Banjir di Daerah Aliran Sungai Welang Kecamatan Kraton. Undergraduate thesis, Institut Teknologi Sepuluh Nopember.

[img]
Preview
Text
08211440000083-Undergraduate_Thesis.pdf - Accepted Version

Download (5MB) | Preview

Abstract

Banjir sebagai salah satu bencana alam yang sering terjadi di Indonesia perlu diwaspai. Menurut BNPB (2017), pada tiga bulan pertama tahun 2017 tercatat sebanyak 25 provinsi dan 121 kabupaten/kota terendam banjir. Salah satu lokasi yang sering terkena banjir adalah Kabupaten Pasuruan, Jawa Timur. Karakteristik topografinya yang dialiri oleh 9 pengaliran sungai, membuat Kabupaten Pasuruan rawan terjadi banjir atau genangan di daerah hilir sungai jika intensitas hujan tinggi (RTRW Kabupaten Pasuruan 2009-2029). Salah satu sungai terbesarnya adalah Welang, yang melintasi tiga daerah administrasi, yaitu wilayah kota dan kabupaten Pasuruan sekaligus berada di hilir, tengah dan hulu melintasi Kabupaten Pasuruan, sedangkan bagian paling hulu ada di Kecamatan Lawang, Kabupaten Malang (BBWS Brantas, 2015). Kecamatan Kraton yang terletak di hilir sungai Welang memiliki potensi terdampak banjir yang cukup tinggi. Menurut data historis kejadian banjir BPBD Kabupaten Pasuruan, setidaknya rata-rata terdapat 3 hingga 4 kali kejadian banjir per tahun di kecamatan ini. Maka dari itu, diperlukan kajian untuk menilai risiko bencana banjir sebagai tahap awal upaya mitigasi agar kedepannya dapat dirumuskan strategi untuk mengurangi risiko tersebut. Dengan menggunakan ancaman dan kerentanan sebagai indikator risiko, dipilihlah 3 variabel ancaman, yaitu ketinggian genangan, curah hujan, dan kemiringan tanah (kelerengan), serta 4 variabel penentu kerentanan, yaitu topografi, tata guna lahan, jenis tanah, dan jarak dari sungai. Metodologi yang digunakan adalah spatial multi-criteria analysis yang juga memanfaatkan AHP untuk menentukan bobot variabel kerentanan. Sedangkan bobot variabel ancaman diasumsikan memiliki tingkat kepentingan yang sama. Dengan memformulasikan ancaman dan kerentanan didapatkan tingkat risiko yang ada di Kecamatan Kraton, yaitu sebanyak 46% masuk dalam kelas berisiko, 45% masuk ke dalam kelas sedikit berisiko, 6,6% tergolong kelas sangat berisiko, dan 2,4% masuk ke dalam kelas berisiko rendah. Dari delapan desa di wilayah studi, didapatkan hasil tiga desa diantaranya memiliki risiko yang sangat tinggi, yaitu Desa Pulokerto, Desa Semare, dan Desa Tambakrejo dengan luas keseluruhan 115,954 Ha. ======================================================================================================== Flood as one of the natural disasters that often occurs in Indonesia needs to be monitored. According to BNPB (2017), until the first three months of 2017 recorded as many as 25 provinces and 121 districts affected. One of those locations is Pasuruan, East Java. Its topography condition which is surrounded by 9 river drainages makes Pasuruan Regency vulnerable to flooding in the downstream area if the rainfall intensity is high (RTRW Kabupaten Pasuruan 2009-2029). One of its largest rivers is Welang, which crosses 3 administrative areas, which are Pasuruan city and regency as the downstream, Pasuruan city in the middle, and Lawang Sub District of Malang Regency as the upstream (BBWS Brantas, 2015). Kraton sub district which is located at downstream of Welang river has high impacted of flooding. According to historical data of flood event from BPBD Pasuruan, at least 3 to 4 times flood occured per year in this district. Therefore, a profound study is needed to assess the risk level of flood disaster as an early stage of mitigation to formulate the future strategies to reduce those risks. Using hazard and vulnerabily as indicators, three variables of hazard were selected, i.e. height of inundation, rainfall intensity, and slope , and four variables of vulnerability, i.e. topography, land use, type of soil, and distance from the river. The methodology applied is spatial multi-criteria analysis (SMCE) that also used AHP to determine the weight of variables of vulnerability. The weight of the hazard variables are assumed to have the same level of importance. By formulating hazard and vulnerability, the risk level in Kraton sub district is founded, 46% are classified in the risk class, 45% classified in the middle risk class, 6.6% belong to very risky class, and 2.4% belong to low-risk classe. Three of eight villages in the study area, are founded to have very high risks, which are Pulokerto, Semare, and Tambakrejo villages with a total area of 115,954 Ha.

Item Type: Thesis (Undergraduate)
Additional Information: RSPW 711.58 Bil z-1 3100018076702
Uncontrolled Keywords: disaster risk, flood, multi-criteria analysis, weighted overlay, zoning
Subjects: G Geography. Anthropology. Recreation > G Geography (General) > G70.212 ArcGIS. Geographic information systems.
G Geography. Anthropology. Recreation > GB Physical geography > GB1399.9 Floods
T Technology > T Technology (General) > T174.5 Technology--Risk assessment.
Divisions: Faculty of Architecture, Design, and Planning > Regional and Urban Planning > 35201-(S1) Undergraduate Thesis
Depositing User: Bilqis Zaqiyyah Salsabila
Date Deposited: 02 Mar 2021 05:55
Last Modified: 02 Mar 2021 05:55
URI: https://repository.its.ac.id/id/eprint/54676

Actions (login required)

View Item View Item