Pengembangan Metode Risiko Rob Akibat Penurunan Muka Tanah di Pesisir Kota Jakarta

SANI AFIFAH, Dr. Dyah Rahmawati Hizbaron, M.T., M.Sc; Dr. Mohammad Pramono Hadi, M.Sc

2022 | Tesis | MAGISTER ILMU LINGKUNGAN

Penelitian ini bertujuan untuk meningkatkan kualitas pemetaan risiko rob akibat penurunan muka tanah guna memenuhi standar Pelayanan Minimal Kebencanaan di tingkat kota. Tujuan penelitian ini secara lebih rinci yaitu 1) menganalisis distribusi genangan rob akibat penurunan muka tanah di Pesisir Kota Jakarta 2) menganalisis tingkat kerentanan kecamatan-kecamatan di Pesisir Kota Jakarta 3) menganalisis tingkat risiko rob akibat penurunan muka tanah di Pesisir Kota Jakarta. Metode interpolasi dilakukan untuk menghasilkan data spasial laju penurunan muka tanah. Iterasi neighbourhood operation digunakan untuk melakukan pemodelan rob. Skema klasifikasi penggunaan lahan dikembangkan agar dapat merepresentasikan kompleksitas sosial ekonomi di level kota. Digitasi on screen dilakukan untuk identifikasi elemen berisiko. Survei lapangan dilakukan untuk pengambilan sampel penggunaan lahan, objek mitigasi, dan validasi risiko secara stratified random sampling. Pengukuran objek mitigasi dilakukan menggunakan GNSS. Confussion matrix dilakukan untuk uji akurasi model. Metode dasymetric-AHP digunakan untuk mengetahui parameter kerentanan sosial berupa distribusi kepadatan penduduk. Penilaian risiko rob di level kota dianalisis berdasarkan peta bahaya dan kerentanan. Hasil pemetaan menunjukkan luas kelas bahaya rendah, sedang, dan tinggi di Pesisir Kota Jakarta secara berturut-turut yaitu 11613.69 Hektar, 331.75 Hektar, dan 436.21 Hektar. Hasil pementaan kerentanan menunjukkan pola yang robust yaitu dominasi kerentanan tinggi di sebagian besar Kecamatan Penjaringan. Selain itu, sebagian kecil kerentanan tinggi terdapat di Kecamatan Cilincing dan Kecamatan Pademangan. Sementara itu, kelas risiko tinggi dominan terjadi pada permukiman kepadatan tinggi. Secara spesifik lokasi tersebut berada di bagian barat RW 001 Kelurahan Kamal Muara dan RW 022 Kelurahan Pluit Kecamatan Penjaringan. Selain itu, lokasi lainnya yaitu di RW 008 Kelurahan Ancol Kecamatan Pademangan dan RW 007 Kelurahan Marunda Kecamatan Cilincing. Area parkir dan pergudangan di Kecamatan Pademangan juga terdampak rob. Lokasi tersebut berada di Pelabuhan Sunda Kelapa yang secara administratif masuk wilayah RW 008 Kelurahan Ancol Kecamatan Pademangan. Upaya mitigasi di lokasi-lokasi tersebut perlu menjadi prioritas karena pengurangan risiko bencana untuk permukiman penduduk dan pusat kegiatan perkotaan dalam dokumen Rencana Tata Ruang Wilayah DKI Jakarta Tahun 2012-2030 baru bersifat programatik. Sementara itu, lokasi spesifik belum terakomodir.

This study aims to improve the quality of tidal risk mapping due to land subsidence to meet the Minimum Disaster Service standards at the city level. The objectives of this study in more detail, namely 1) analyzing the distribution of tidal flood inundation due to land subsidence in the Coastal City of Jakarta 2) analyzing the level of vulnerability of the sub-districts in the Coastal City of Jakarta 3) analyzing the level of tidal risk flood due to land subsidence in the Coastal City of Jakarta. The interpolation method was conducted to produce spatial data on the rate of land subsidence. Iteration of the neighborhood operation is used to perform rob modeling. The land use classification scheme was developed to represent socio-economic complexities at the city level. On-screen digitization is carried out to identify risk elements. Field surveys were conducted for land use sampling, mitigation objects, and risk validation by stratified random sampling. The measurement of the mitigation object was carried out using GNSS. The confusion matrix was done to test the accuracy of the model. The dasymetric-AHP method was conducted to determine the parameters of social vulnerability in the form of population density distribution. The tidal flood risk assessment at the city level is analyzed based on the hazard and vulnerability map. The mapping results show the area of low, medium, and high hazard classes in the Coastal City of Jakarta, respectively 11613.69 hectares, 331.75 hectares, and 436.21 hectares. The results of the vulnerability assessment show a robust pattern. The dominance of high vulnerability in most of the Penjaringan sub-districts. In addition, a small proportion of high vulnerability was found in Cilincing and Pademangan sub-districts. Meanwhile, the high-risk class dominantly occurs in high-density settlements. Specifically, the location is in the western part of RW 001 and RW 022 Kamal Muara Village, Pluit Village, Penjaringan District. In addition, the other locations are RW 008, Ancol Village, Pademangan District, and RW 007, Marunda Village, and Cilincing District. The parking and warehousing area in the Pademangan District was also affected by the tidal flood. Precisely in the Sunda Kelapa Harbor which is administratively included in the area of RW 008, Ancol Village, Pademangan District. Mitigation efforts in these locations need to be a priority because disaster risk reduction for residential areas and centers of urban activity in the 2012-2030 DKI Jakarta Spatial Planning document is only programmatic. Meanwhile, specific locations have not been accommodated.

Kata Kunci : Penurunan Muka Tanah, Risiko Rob, GNSS, Dasymetric-Analytical Hierarchy Process (AHP), Pesisir Kota Jakarta