Land Use Change and Its Impacts on Surface Runoff in Rural Areas of the Upper Citarum Watershed (Case Study: Cirasea Sub-watershed)

Zahrul Atharinafi, Nurrohman Wijaya

Abstract


Land-use change in upstream regions is a recognized driver of the increase in surface runoff, resulting in increasing flood intensity and occurrence. The rapid urbanization of outlying districts surrounding large metropolitan areas is a known driver of land-use change. Therefore, we study land-use change patterns within the Cirasea Sub-watershed within the last 20 years and changes in the runoff coefficient within the same time frame. This paper examines how land-use change patterns on the outskirts of the Bandung Metropolitan Area influence runoff. Spatial analysis and surface runoff calculation using the curve number method were applied. The study found significant changes in land use, particularly in the watershed’s southern reaches, whereby forest and shrub land gave way to agriculture in a water recharge zone, resulting in an increased runoff coefficient upstream. Urbanization within the Cirasea Sub-watershed did not encroach into areas identified as recharge zones and had a minimal direct impact on increased runoff. Aggregate runoff coefficient (curve number) in the Cirasea Sub-watershed increased from 70.98 in 1999 to 72.04 in 2018. For a design 24-hour period rainfall of 120 mm, runoff increased from 48.49 mm (1999) to 51.8 mm (2018). We conclude that the changes above in land use have increased runoff in the Cirasea Sub-watershed. Furthermore, land-use policies laid down by the RTRW Bandung Regency for 2016-2036 provide provisions to reforest previously deforested areas, with deforested areas being zoned as protected forest. Therefore, we propose promoting agroforestry as part of land use policy in order to restore runoff to its 1999 level under existing land use planning policy.

Abstrak. Perubahan guna lahan pada wilayah hulu diketahui sebagai salah satu penyebab peningkatan limpasan air permukaan, meningkatkan intensitas dan frekeuensi banjir. Urbanisasi pesat pada wilayah pinggiran kawasan metropolitan diketahui sebagai faktor pendorong terjadinya perubahan guna lahan. Berdasarkan kondisi tersebut, kami melakukan studi terhadap pola perubahan guna lahan pada Sub-DAS Cirasea, pada 20 tahun terakhir, serta perubahan limpasan air permukaan pada rentang waktu yang sama. Paper ini meneliti bagaimana perubahan guna lahan pada wilayah pinggiran Metropolitan Bandung Raya mempengaruhi limpasan air permukaan. Analisis spasial dan perhitungan limpasan air permukaan dilakukan, menggunakan metode bilangan kurva. Berdasarkan hasil studi, diketahui telah terjadi perubahan guna lahan yang signifikan pada wilayah hulu DAS. Hutan dan semak belukar berubah menjadi kawasan pertanian, pada wilayah resapan air tanah, sehingga terjadi peningkatan limpasan air permukaan di wilayah hulu. Urbanisasi pada wilayah Sub-DAS Cirasea diketahui tidak menjalar hingga wilayah resapan air tanah dan memiliki dampak minim terhadap kenaikan limpasan air permukaan. Angka koefisien limpasan air permukaan (bilangan kurva) di DAS Cirasea meningkat dari 70.98 (1999), menjadi 72.04 (2018). Pada curah hujan (asumsi) 24 jam sebesar 120mm, limpasan air permukaan meningkat dari 48.49mm (1999), menjadi 51.8mm (2018). Berdasarkan hasil tersebut, kami simpulkan bahwa perubahan guna lahan telah mengakibatkan peningkatan limpasan air permukaan di DAS Cirasea.  

Kata kunci.Perubahan tata guna lahan, potensi aliran permukaan, DAS citarum hulu, pencegahan banjir.


Keywords


land use change; surface runoff potential; upper citarum watershed; flood prevention

Full Text:

PDF

References


Ardiwijaya, V., T. Soemardi, E. Suganda and Y. Temenggung (2014) Bandung Urban Sprawl and Idle Land: Spatial Environment Perspectives. APCBEE Procedia 10.

Asdak, C. (2001) Hidrologi dan Pengelolaan Daerah Aliran Sungai. UGM Press.

Balai Besar Wilayah Sungai Citarum (2016) Rencana Pengelolaan Sumber Daya Air WS Citarum.

Batty, M., E. Besussi, and N. Chin (2003) Traffic, Urban Growth and Suburban Sprawl. UCL Centre for Advanced Spatial Analytics Working Papers 70.

Budiyantini, Y., and V. Pratiwi (2016) Peri-Urban Typology of Bandung Metropolitan Area. Procedia - Social and Behavioral Sciences 227, 833-937.

Fantina, D.E. (2012) A Comparison of Runoff Estimation Techniques. (white paper)

Firman, T. (1996) Urban Development in Bandung Metropolitan Region: A Transformation to A Desa-Kota Region. Third World Planning Review 18(1).

Firman, T. (2000) Rural to Urban Land Conversion in Indonesia During Boom and Bust Periods. Land Use Policy 17(1).

Hapsari, S.V.E. (2019) Potensi Agroforestri dalam Pengurangan Tingkat Erosi dan Peningkatan Pendapatan Masyarakat Sebagai Upaya Konservasi Lahan di Desa Tarumajaya, Kecamatan Kertasari, Kabupaten Bandung. Bandung Institute of Technology.

Hudalah, D., H. Winarso, and J. Woltjer (2007) Peri-Urbanisation in East Asia: A new challenge for planning? International Development Planning Review 29(4).

Hudalah, D., H. Winarso, and J. Woltjer (2016) Gentrifying the Peri-Urban: Land Use Conflicts and Institutional Dynamics at The Frontier of An Indonesian Metropolis. Urban Studies 53(3).

Hutagaol, R.R., and S. Hardwinanto (2011) Pengaruh Perubahan Tata Guna Lahan Terhadap Debit Limpasan pada Sub-DAS Sepauk, Kabupaten Sintang, Kalimantan Barat. Jurnal Kehutanan Tropika Humida 4(1).

Ideawati, L.F., L.M. Limantara, and U. Andawayanti (2015) Analisis Perubahan Bilangan Kurva Aliran Permukaan (Runoff Curve Number) terhadap Debit Banjir di DAS Lesti. Jurnal Pengairan 6(1).

Kim, G.S., C.H. Lim, S.J. Kim, J. Lee, Y. Son, and W.K. Lee (2017) Effect of National Scale Afforestation on Forest Water Supply and Soil Loss in South Korea, 1971-2010. Sustainability 9(6).

Ly, S., C. Charles, and A. Degre (2011) Geostatical Interpolation of Daily Rainfall at Catchment Scale: The Use of Several Variogram Models in The Ourthe and Ambleve Catchments, Belgium. Hydrology and Earth System Sciences 15(7).

Morin, J. (1993) Rainfall Analysis for Tillage Management. In Soil Tillage in Africa: Needs and challenges. Rome, Italy: Food and Agricultural Organization.

Pemerintah Provinsi Jawa Barat (2014) Peraturan Daerah Jawa Barat Nomor 12 Tahun 2014 tentang Pengelolaan Pembangunan dan Pengembangan Metropolitan dan Pusat Pertumbuhan di Jawa Barat.

Pemerintah Provinsi Jawa Barat (2018) Peraturan Presiden Nomor 45 Tahun 2018 tentang Rencana Tata Ruang Kawasan Perkotaan Cekungan Bandung.

Piorr, A., J. Ravetz and I. Tosics, I. (n.d.). Peri-Urbanisation in Europe: Towards European Policies to Sustain Urban-Rural Futures. Fredericksburg, Denmark: Forest & Landscape, University of Copenhagen.

Republik Indonesia. Undang Undang Nomor 26 Tahun 2007 tentang Penataan Ruang.

Rohman, S. (2014) Tekanan Penduduk di Sekitar Kawasan Hutan Sub Daerah Aliran Sungai Cisangkuy Hulu, Kabupaten Bandung. Indonesia University of Education.

Rosyidie, A. (2013) Banjir: Fakta dan Dampaknya, serta Pengaruh dari Perubahan Guna Lahan. Jurnal Perencanaan Wilayah dan Kota 24(3).

Salim, E., S.M. Adieoetomo, E.N. Arifin, and A. Pratama (2015) Population Dynamics and Sustainable Development in Indonesia. Jakarta, Indonesia: UNFPA Indonesia.

Thompson, D. B. (2006) The Rational Method.

Tikno, S., T. Hariyanto, A. Nadjadji, A. Karsidi, and E. Aldrian (2012) Aplikasi Metode Bilangan Kurva untuk Merepresentasikan Hubungan Curah Hujan dan Aliran Permukaan di DAS Ciliwung Hulu-Jawa Barat. Jurnal Teknik Lingkungan 13(1).

USDA Natural Resources Conservation Service. (2009) Chapter 7, Hydrologic Soil Groups. In National Engineering Handbook: Part 630 Hydrology.

USDA Soil Conservation Service. (1986) Urban Hydrology for Small Watersheds, TR - 55.

Vandas, S.J., T.C. Winter, and W.A. Battaglin (2002) Water and the Environment. Alexandria, VA: American Geological Institute.

Verbeiren, B., T. Van de Voorde, M. Binard, Y. Cornet, J. van der Kwaast, G. Engelen, and O. Batelaan, O. (2011) Impact Assessment of Urbanisation on Hydrology for the River Tolka in Dublin, Ireland: A Case Study of Remote Sensing Supported Hydrological Modelling. Proceedings of the National Hydrology Conference 2011. Presented at the National Hydrology Conference 2011, Athlone County, Ireland.

Webster, D. (2002) On the Edge: Shaping the Future of Peri-Urban East Asia. Stanford, CA: Asia/Pacific Research Center.

Wijaya, N. (2015) Deteksi Perubahan Penggunaan Lahan dengan Citra Landsat dan Sistem Informasi Geografis: Studi Kasus di Wilayah Metropolitan Bandung, Indonesia. Journal of Geomatics and Planning 2(2).




DOI: http://dx.doi.org/10.5614%2Fjpwk.2021.32.1.3

© 2020 Institut Teknologi Bandung