Structural and Green Infrastructure Mitigation Alternatives Prevent Ciliwung River from Water-related Landslide

Abstract

Landslide is one of the most dangerous hazards worldwide. It could be caused by several factors and could have a massive destructive impact on the environment. A landslide event occurred in one of the urban cities in Indonesia. In the middle of 2002, a landslide disaster due to rainfall occurred in the Ciliwung River's floodplain, precisely in the South Jakarta area. The landslide profoundly affected large areas of the region and seriously injured many people. Several circumstances that could trigger landslide occurrences are the building load in the settlement area around the river, increase in the rainfall intensity, slope, and soil characteristics in the Ciliwung River area. This research proposes a combination of nonstructural and structural disaster mitigation methods for water-related landslide by investigating the safety factor (SF) of the river bank's slope in one of the impacted sites, i.e., the area under the main bridge of Grand Depok City regency. This site is located in the boundary area between Depok City and South Jakarta. The authors simulate analytical and numerical modeling to estimate the SF of the slopes. This research concludes that the minimum SF in the analyzed location is recognized as a safety criterion for society. The condition becomes less secure when an earthquake occurs. Furthermore, high rainfall intensity could become the worst scenario that generates considerable damage. The proposed structural mitigation for river bank with anchor or snail increases the SF. However, this reinforcement program is not recommended because of its high cost and ineffectiveness in solving problems. Hence, green infrastructure (GI) is highly suggested for nature-based mitigation to prevent rainfall-triggered landslides in the Ciliwung River area. The authors conduct the preliminary design of the study and recommend further analysis of GI or soil bioengineering to ensure its effectiveness and applicability in the research area.

Mitigasi Banjir Struktural Menggunakan Model Hec-Ras Dan Geo-Studio Pada Wilayah Sungai Toba-Asahan, Sumatera Utara

“…(Zhao, Tong and Lü, 2014) dengan beberapa komponen gaya seperti beban bidang (Wi), gaya gempa horizontal (Qci), beban horizontal dan vertikal (Qxi, Qyi), tekanan air (Ui), gaya antaririsan (Ei, Xi, Ei+1, Xi+1), gaya normal (Ni), dan kekuatan geser (Ti) pada permukaan. Sketsa ini merupakan pengembangan baru metode irisan dibandingkan metode konvensional yang biasa digunakan pada konsep dasar Geo-Studio (Prastica, Apriatresnayanto and Marthanty, 2019).…”

“…Dalam melakukan suatu keputusan penanganan bencana, pemerintah memerlukan rencana anggaran biaya yang perlu dialokasikan. Bila pengendalian banjir hanya mengandalkan mitigasi struktural, maka pemerintah akan mengeluarkan biaya besar (Prastica, Apriatresnayanto and Marthanty, 2019). Terlebih lagi, bila mitigasi struktural ini akan berkelanjutan dari waktu ke waktu tanpa mitigasi non-struktural di daerah tinjauan.…”

“…Hal ini sama halnya dengan kekurangan air dengan bencana kekeringan (Shenava and Shourian, 2018), kelebihan air dengan adanya bencana banjir menjadi perhatian banyak pemangku kepentingan (Stephenson, Finlayson and Morel, 2018). Satu dekade terakhir, banyak penelitian terkait pengendalian banjir baik struktural (Alam et al, 2018) maupun non-struktural tidak hanya di Indonesia (Prastica, Apriatresnayanto and Marthanty, 2019), tetapi juga di dunia (Price and Vojinovic, 2008;Broekhuizen et al, 2019). Penelitian terkait mitigasi struktural melakukan klaim bahwa mitigasi dengan cara ini dinilai lebih efektif dalam reduksi volume banjir (Andersen et al, 2011;Lempérière, 2017;Ezzine et al, 2020).…”

Grey and green infrastructure alternatives for water-related disaster mitigation: the case of Mandailing Natal, North Sumatera, Indonesia

“…Meanwhile, the non-structural mitigation involves green infrastructures which could help to reduce flood as low impact development (LID) [24]- [26] and best management practices (BMP) [27], [28]. The strategies of LID and BMP are widely applied and proven to make the flood impact inclination in both rural and urban areas, such as the application of permeable pavement [28], [29], green roof [28], [30], [31], wetland [32], and rainwater harvesting [22], [33], [34].…”

Keefektifan Penambahan Kapasitas Saluran dan Dinding Penahan Tanah pada Sungai Brantas Hulu di Kediri dalam Mitigasi Banjir

“…Kajian mitigasi bencana telah banyak dilakukan oleh penelitian sebelumnya. Beberapa penelitian merekomendasikan adanya infrastruktur hijau yang dapat diterapkan di suatu kota untuk mereduksi banjir (Liu and Li, 2016;Kourtis, Tsihrintzis and Baltas, 2018;Machado, Oliveira and Lois-González, 2019;Prastica, Apriatresnayanto and Marthanty, 2019). Namun, beberapa penelitian menyimpulkan bahwa pembangunan infrastruktur fisik seperti bendungan dan intervensi pada hidrolika bangunan air juga dapat mereduksi dampak banjir yang terjadi (Nieto et al, 2013;Wedawatta et al, 2016;Prastica et al, 2017;Tedford and Ellison, 2018;Yazdi, 2018).…”