Arahan Mitigasi Bencana Banjir di Kawasan Agropolitan Kecamatan Bagelen Kabupaten Purworejo

SANTIKA P, Prof. Dr. rer.nat. Junun Sartohadi, M.Sc.; Dr. Lutfi Muta'ali, S.Si., M.T.

2020 | Tesis | MAGISTER MANAJEMEN BENCANA

Banjir merupakan bencana yang terjadi setiap tahun di Indonesia. Salah satu wilayah yang sering dilanda banjir adalah Kecamatan Bagelen di Kabupaten Purworejo Provinsi Jawa Tengah. Kejadian banjir di Kecamatan Bagelen mengganggu fungsi pengembangan perekonomian wilayah sebagai pusat agropolitan yang bertanggungjawab atas pelayanan utama kawasan. Penelitian ini dimaksudkan untuk menentukan arahan mitigasi bencana banjir yang sesuai di kawasan agropolitan. Metode analisis yang digunakan Participatory GIS dan deskriptif kualitatif untuk mengetahui karakteristik ancaman banjir. Teknik overlay peta ancaman banjir dengan peta elemen kawasan agropolitan, serta deskriptif kualitatif ditujukan untuk mengetahui elemen kawasan agropolitan yang berpotensi terdampak banjir. Selanjutnya, arahan mitigasi bencana banjir yang sesuai dipilih dengan mempertimbangkan karakteristik ancaman, serta elemen kawasan agropolitan yang berpotensi terdampak banjir. Hasil penelitian menunjukkan bahwa kawasan agropolitan di Kecamatan Bagelen rawan banjir. Terdapat tiga kelas ancaman, yaitu rendah (1,17%), sedang (10,77%), dan tinggi (88,06%). Semua tanaman dan infrastruktur pertanian rawan terdampak banjir karena luapan sungai utama maupun luapan anak-anak sungainya. Mitigasi bencana banjir yang seharusnya ada di kawasan agropolitan meliputi: (1) upaya managemen tanaman, (2) menajemen infrastruktur kawasan agropolitan, (3) manajemen sistem drainase dan irigasi. Upaya mitigasi tersebut tidak dipisahkan dari upaya mitigasi banjir yang sifatnya umum pada sistem DAS, yang meliputi: (1) pemeliharaan kapasitas penyimpanan air, (2) peningkatan kapasitas sungai untuk membuang air, (3) pengelolaan tepian sungai untuk melindungi lahan pertanian di sekitar sungai.

Flooding is an annual disaster in Indonesia. One area that is often hit by floods is Bagelen Sub-district in Purworejo Regency, Central Java Province. The occurrence of floods in Bagelen Subdistrict disrupts the function of regional economic development as the center of agropolitan area which is responsible for the region's main services. This research aims to determine the most suitable flood mitigation strategies in agropolitan area. The analysis method employed to achieve the research objective was Participatory GIS and descriptive qualitative to find out the flood hazard characteristics of Bagelen Sub-district. Overlaying flood hazard map and maps of agropolitan area elements, as well as descriptive qualitative is intended to find out the elements of agropoliran areas that are potentially affected by flooding. Then, the most suitable flood mitigation strategies are chosen by considering the characteristics of flood hazard, as well as the elements of agropolitan area that are potentially affected by flood. The result show that the agropolitan area in the Bagelen Sub-district is suffering by flood hazards. There were three classes of natural hazard, namely low (1,17%), moderate (10,77%), and high (88,06%). All the crops and agricultural land infrastructure are becoming vulnerable to be affected by flood both due to flood from the main river and flood from the local canals ended at the main river. The flood mitigation strategies in the agropolitan area should include: (1) crop management efforts, (2) agricultural land infrastructure management, (3) irrigation and drainage systems management. Those mitigation effort would not be separated from the overall flood mitigation in the watershed systems, that cover: (1) maintenance the water storage capacity, (2) river capacity improvement to discharge water, (3) river bank management to protect agricultural land at the surrounding canals.

Kata Kunci : arahan, mitigasi, ancaman banjir, agropolitan