MITIGASI BANJIR STRUKTURAL MENGGUNAKAN MODEL HEC-RAS DAN GEO-STUDIO PADA WILAYAH SUNGAI TOBA-ASAHAN, SUMATERA UTARA

Rian Mantasa Salve Prastica; Aditya Widyatmoko; Rezky Kurniawan

doi:10.29103/tj.v11i2.519

MITIGASI BANJIR STRUKTURAL MENGGUNAKAN MODEL HEC-RAS DAN GEO-STUDIO PADA WILAYAH SUNGAI TOBA-ASAHAN, SUMATERA UTARA

Rian Mantasa Salve Prastica, Aditya Widyatmoko, Rezky Kurniawan

Abstract

Abstrak

Permasalahan banjir menjadi isu utama di Indonesia dan di dunia. Strategi manajemen pengendalian banjir dapat berupa upaya mitigasi struktural dan non-struktural. Adanya perkembangan penelitian menyebutkan bahwa mitigasi non-struktural memiliki dampak yang baik dalam mereduksi banjir. Penelitian ini mengambil studi kasus di daerah studi yaitu Wilayah Sungai Toba-Asahan, tepatnya di Sungai Silau. Apakah mitigasi struktural dalam pengendalian banjir signifikan? Analisis kapasitas hidrolika menggunakan software HEC-RAS adanya penurunan limpasan banjir dari kondisi eksisting ke kondisi skenario normalisasi sungai. Begitu pula nilai safety factor lereng sungai pada lokasi tinjauan menggunakan software Geo-Studio yang naik sebesar 139%. Opsi usulan desain bendungan urugan juga dapat mereduksi banjir sebesar 24,83%. Sehingga, dapat disimpulkan bahwa mitigasi struktural signifikan dalam pengendalian banjir. Namun, mitigasi struktural tidak bersifat sustainable bagi pemangku kepentingan, sehingga perlu ada skenario simulasi menggunakan mitigasi non-struktural.

Kata kunci: pengendalian banjir, mitigasi struktural, mitigasi non-struktural, flood routing

Abstract

The problem of flooding is a major issue in Indonesia and in the world. Flood control management strategies can take the form of structural and non-structural mitigation measures. The development of research states that non-structural mitigation has a good impact in reducing flooding. This research took a case study in the study area, namely the Toba-Asahan River Basin, to be precise in the Silau River. Is structural mitigation in flood control significant? Analysis of hydraulic capacity using HEC-RAS software shows a decrease in flood runoff from existing conditions to river normalization scenario conditions. Likewise, the river slope safety factor value at the review location using Geo-Studio software increased by 139%. The proposed option for embankment dam design can also reduce flooding by 24.83%. Thus, it can be concluded that structural mitigation is significant in flood control. However, structural mitigation is not sustainable for stakeholders, so there needs to be a simulation scenario using non-structural mitigation.

Keywords: flood management, structural mitigation, non-structural mitigation, flood routing

Keywords

flood management, structural mitigation, non-structural mitigation, flood routing

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References

Abdi, R., Endreny, T. and Nowak, D, 2020. A model to integrate urban river thermal cooling in river restoration. Journal of Environmental Management. Elsevier Ltd, 258(July 2019), p. 110023. doi: 10.1016/j.jenvman.2019.110023.

Abon, C. C., David, C. P. C. and Tabios, G. Q, 2012. Community-based monitoring for flood early warning system: An example in central Bicol River basin, Philippines. Disaster Prevention and Management, 21(1), pp. 85–96. doi: 10.1108/09653561211202728.

Alam, A. et al, 2018. Flood risk assessment of Srinagar city in Jammu and Kashmir, India. International Journal of Disaster Resilience in the Built Environment, 9(2), pp. 114–129. doi: 10.1108/IJDRBE-02-2017-0012.

Andersen, D. C. et al, 2011. Managed flood effects on beaver pond habitat in a desert riverine ecosystem, bill williams river, Arizona USA. Wetlands, 31(2), pp. 195–206. doi: 10.1007/s13157-011-0154-y.

Balai Wilayah Sungai (BWS) II, 2013. Pola Pengelolaan Sumber Daya Air Wilayah Sungai Toba Asahan. pp. 1–115.

Bang, H., Miles, L. and Gordon, R, 2019. Evaluating local vulnerability and organisational resilience to frequent flooding in Africa: the case of Northern Cameroon. Foresight, 21(2), pp. 266–284. doi: 10.1108/FS-06-2018-0068.

Braga, A. et al, 2018. Performance of two advanced rainwater harvesting systems in Washington DC. Water (Switzerland), 10(5), pp. 1–13. doi: 10.3390/w10050667.

Broekhuizen, I. et al, 2019. Urban drainage models for green areas : Structural differences and their effects on simulated runoff. Journal of Hydrology X. Elsevier, 5(October), p. 100044. doi: 10.1016/j.hydroa.2019.100044.

Chow, V. Te et al, 1998. Applied Hydrology. pp. 1–294. Available at: http://ponce.sdsu.edu/Applied_Hydrology_Chow_1988.pdf.

Cojoc, G. M., Romanescu, G. and Tirnovan, A, 2015. Exceptional floods on a developed river: case study for the Bistrita River from the Eastern Carpathians (Romania). Natural Hazards. Springer Netherlands, 77(3), pp. 1421–1451. doi: 10.1007/s11069-014-1439-2.

Dinas Tata Kota Kabupaten Asahan, 2012. Laporan Akhir Penyusunan DED Drainase Primer di Kota Kisaran. Medan.

Ezzine, A. et al, 2020. Flood mapping using hydraulic modeling and Sentinel-1 image: Case study of Medjerda Basin, northern Tunisia. Egyptian Journal of Remote Sensing and Space Science. National Authority for Remote Sensing and Space Sciences, 23(3), pp. 303–310. doi: 10.1016/j.ejrs.2020.03.001.

Farooq, M., Shafique, M. and Khattak, M. S, 2019. Flood hazard assessment and mapping of River Swat using HEC-RAS 2D model and high-resolution 12-m TanDEM-X DEM (WorldDEM). Natural Hazards. Springer Netherlands, 97(2), pp. 477–492. doi: 10.1007/s11069-019-03638-9.

Frans, J. H. and Halema, E. U. M, 2019. Analisis Parameter Alfa Hidrograf Satuan Sintetik Nakayasu Pada Das Di Pulau Flores. Jurnal Teknik Sipil, 8(2), pp. 227–240.

GEO-SLOPE International Ltd, 2012. Stability Modeling with SLOPE / W. July 2012. Calgary, Alberta, Canada: GEO-SLOPE International Ltd. Available at: www.geo-slope.com.

Guven, H. and Tanik, A, 2018. Water-energy nexus: Sustainable water management and energy recovery from wastewater in eco-cities. Smart and Sustainable Built Environment, 9(1), pp. 54–70. doi: 10.1108/SASBE-07-2017-0030.

Harahap, R, 2013. Penentuan Indeks Banjir sebagai Peringatan Siaga Berdasarkan Analisis Debit pada Sungai Asahan. Jurnal Saintika, 14(2), pp. 109–118.

Kumar, N. et al, 2019. Applicability of HEC ‑ RAS 2D and GFMS for flood extent mapping : a case study of Sangam area , Prayagraj , India. Modeling Earth Systems and Environment. Springer International Publishing, (0123456789). doi: 10.1007/s40808-019-00687-8.

Lempérière, F, 2017. Dams and Floods. Engineering. Elsevier LTD on behalf of Chinese Academy of Engineering and Higher Education Press Limited Company, 3(1), pp. 144–149. doi: 10.1016/J.ENG.2017.01.018.

Lin, E., Shaad, K. and Girot, C, 2016. Developing river rehabilitation scenarios by integrating landscape and hydrodynamic modeling for the Ciliwung River in Jakarta, Indonesia. Sustainable Cities and Society. Elsevier B.V., 20, pp. 180–198. doi: 10.1016/j.scs.2015.09.011.

Lukman, A, 2017. Penelusuran Kawasan Daerah Aliran Sungai ( DAS ) Asahan. Buletin Utama Teknik, 13(1), pp. 49–54.

Mohamed, A. and Worku, H, 2020. Urban land cover and morphometric analysis for flash flood vulnerability mapping and riparian landscape conservation in Kebena River watershed, Addis Ababa. Applied Geomatics. Applied Geomatics. doi: 10.1007/s12518-020-00318-3.

Mohit, M. A. and Sellu, G. M, 2013. Mitigation of Climate Change Effects through Non-structural Flood Disaster Management in Pekan Town, Malaysia. Procedia - Social and Behavioral Sciences. Elsevier B.V., 85, pp. 564–573. doi: 10.1016/j.sbspro.2013.08.385.

Piotrowski, A. P., Osuch, M. and Napiorkowski, J. J, 2019. Joint Optimization of Conceptual Rainfall-Runoff Model Parameters and Weights Attributed to Meteorological Stations. Water Resources Management, 33(13), pp. 4509–4524. doi: 10.1007/s11269-019-02368-8.

Prastica, R. M. S., Apriatresnayanto, R. and Marthanty, D. R, 2019. Structural and green infrastructure mitigation alternatives prevent Ciliwung River from water-related landslide. International Journal on Advanced Science, Engineering and Information Technology, 9(6), pp. 1825–1832.

Price, R. K. and Vojinovic, Z, 2008. Urban food disaster management. Urban Water Journal, 5(3), pp. 259–276. doi: 10.1080/15730620802099721.

Rousseau, Y. Y., Van de Wiel, M. J. and Biron, P. M, 2017. Simulating bank erosion over an extended natural sinuous river reach using a universal slope stability algorithm coupled with a morphodynamic model. Geomorphology. Elsevier B.V., 295, pp. 690–704. doi: 10.1016/j.geomorph.2017.08.008.

Rubinato, M. et al, 2019. Urban and river flooding: Comparison of flood risk management approaches in the UK and China and an assessment of future knowledge needs. Water Science and Engineering. Elsevier Ltd, 12(4), pp. 274–283. doi: 10.1016/j.wse.2019.12.004.

Saputra, A. A., Saputro, D. D. and Prastica, R. M. S, 2021. Initial investigation of hydraulics engineering for flood mitigation: A case study in Krueng Aceh Sub-watershed. in IOP Conference Series: Earth and Environmental Science. doi: 10.1088/1755-1315/622/1/012002.

Setyoasri, Y. P. and Prastica, R. M. S, 2020. Rapid assessment of river watershed health and vulnerability level for restoration strategy: A study of river systems in Indramayu, West Java, Indonesia. IOP Conference Series: Earth and Environmental Science, 423(1). doi: 10.1088/1755-1315/423/1/012016.

Shenava, N. and Shourian, M, 2018. Optimal Reservoir Operation with Water Supply Enhancement and Flood Mitigation Objectives Using an Optimization-Simulation Approach. Water Resources Management. Water Resources Management, 32(13), pp. 4393–4407. doi: 10.1007/s11269-018-2068-4.

Shole, D. G. and Belayneh, M. Z, 2019. The effect of side slope and clay core shape on the stability of embankment dam: Southern Ethiopia. International Journal of Environmental Science and Technology. Springer Berlin Heidelberg, 16(10), pp. 5871–5880. doi: 10.1007/s13762-019-02228-3.

Stephenson, V., Finlayson, A. and Morel, L. M, 2018. A risk-based approach to shelter resilience following flood and typhoon damage in rural Philippines. Geosciences (Switzerland), 8(2). doi: 10.3390/geosciences8020076.

Sukmana, A. et al, 2013. Bencana Mengepung, Selamatkan DAS Asahan! Kabupaten Simalungun, Sumatera Utara. Kementerian Kehutanan, Badan Penelitian dan Pengembangan Kehutanan.

Wedawatta, G. et al, 2016. Disaster risk reduction infrastructure requirements for South-Western Bangladesh: Perspectives of local communities. Built Environment Project and Asset Management, 6(4), pp. 379–390. doi: 10.1108/BEPAM-06-2015-0022.

Zevri, A. and Isma, F, 2021. Studi Keseimbangan Air (Water Balanced) Daerah Aliran Sungai Asahan. Teras Jurnal, 11(1), pp. 1–16.

Zhao, Y., Tong, Z.-Y. and Lü, Q, 2014. Slope Stability Analysis Using Slice-Wise Factor of Safety. Mathematical Problems in Engineering, 2014, pp. 1–6. Available at: https://econpapers.repec.org/RePEc:hin:jnlmpe:712145.

DOI: https://doi.org/10.29103/tj.v11i2.519