COASTAL COMMUNITY ADAPTATION TO TIDAL FLOOD INUNDATION (Case Study in Tegal Municipality)
Riswan Septriayadi, Dr. rer. nat. Aris Marfai, S.Si., M.Sc.,
2012 | Tesis | S2 GeografiGenangan banjir pasang (rob) di kota Tegal telah mengakibatkan permukiman dan infrastruktur public, seperti jalan dan sistem pengairan, tergenang dan tidak dapat dimanfaatkan secara baik. Rumah tangga yang terkena dampak dan pemerintah kota Tegal telah melakukan berbagai penanganan dalam mengendalikan banjir rob, baik secara struktural dan non-struktural. Namun, berbagai upaya tersebut tidak banyak membantu dalam mengurangi dampak dari banjir rob dikarenakan oleh pendekatan parsial dalam pengelolaan banjir rob. Tujuan-tujuan dari penelitian ini antara lain (a) memahami persepsi masyarakat lokal dan pemerintah terhadap genangan bajir rob (b) menganalisis resiko rumah tangga terhadap genangan banjir rob (c) menilai perkembangan genangan banjir rob dimasa mendatang, dan (d) memberi rekomendasi strategi adaptasi dalam menghadapi dampak genangan banjir rob di masa mendatang. Sebanyak 108 rumah tangga digunakan sebagai sampel untuk mewakili rumah tangga yang terkena dampak. Tokoh kunci dipilih menggunakan snowball sampling. Berbagai pendekatan partisipatif, seperti wawancara mendalam, dan SIG-partisipatif, menjadi alat yang penting dalam pengumpulan data primer. Pangumpulan data sekunder dilakukan melalui survei instanstional. Analisis SIG berbasis data raster dan vector sangat bermanfaat dalam pencapaian tujuan penelitian. Baik rumah tangga dan pemerintah sadar atas kejadian dan kerentanan daerah mereka terhadap genangan banjir rob. Mereka merasakan bahwa penyebab utama dari genangan banjir rob berasal dari alam dan perilaku manusia. Sebagian besar rumah tangga merasakan bahwa kondisi mereka saat ini masih aman. Tidak ada keinginan untuk pindah ke tempat lain. Alasan utama untuk menetap di lokasi sekarang adalah bangunan milik pribadi, akses terhadap tempat kerja, dan biaya hidup yang relatif murah. Banjir rob telah dianggap sebagai peristiwa biasa. Rumah tangga di daerah penelitian didominasi oleh indeks resiko rendah. Hal ini disebabkan oleh berbagai strategi adaptasi yang diterapkan secara mandiri oleh rumah tangga yang terkena dampak dan pemerintah kota Tegal. Berbagai scenario berbeda genangan banjir rob memberikan dampak yang berbeda pada penggunaan lahan. Muarareja diperkirakan menjadi area yang pertama kali terkena dampak kenaikan genangan banjir rob. Semakin tinggi scenario dalam genangan, semakin luas area tergenang. Rumah tangga menyebutkan bahwa prioritas strategi adaptasi adalah rehabilitasi sungai dan saluran pengairan, peninggian dan pavingisasi jalan, pemasangan dan peninggian tanggul sungai, dan pemasangan pintu air. Tindakantindakan yang diajukan pemerintah secara umum adalah secara struktural, seperti pembangunan kolam penampungan yang dilengkapi dengan pompa air dan pintu air otomatis, pengaturan sistem drainase, peninggian jalan di area terkena genangan banjir rob, dan pemasangan bendungan karet. Strategi adaptasi mendatang diharapkan dapat memasukkan persepsi rumah tangga. Keterlibatan dan partisipasi rumah tangga dalam berbagai tindakan nonstruktural untuk mengurangi resiko terhadap genangan banjir rob sangat disarankan. Data raster dalam aplikasi SIG sangat bermanfaat dalam pemodelan genangan banjir rob. Strategi adaptasi terencana lebih disarankan daripada strategi adaptasi mandiri untuk mencegah perkembangan maladaptasi di wilayah kepesisiran kota Tegal.
A great extent of settlement area and public infrastructures, such as roads and drainage systems, are inundated and cannot be fully utilized due to tidal flood inundation in northern coastal area of Tegal municipality. Affected households and government of Tegal municipality have undertaken various measures in controlling tidal flood, both structurally and non-structurally. However, these efforts do not help much in reducing the impact of tidal flood due to a partial approach in managing the tidal flood inundation. Aims of the research are (1) to understand local households and government perception to tidal flood inundation, (2) to analyze current risk of households to tidal flood inundation, (3) to assess the development of future tidal flood inundation, (4) to recommend adaptation strategy in facing future tidal flood inundation impacts. As many as 108 households were taken as respondents by using purposive sampling to represent population of affected households. Key person (community leaders and government officers) as source of invaluable information was selected snowball sampling. Participatory approaches, such as indepth interviews and participatory GIS, provide useful tools in primary data collection. Secondary data are mainly collected by institutional survey. GIS analysis based on raster and vectors data are highly utilized in achieving research objectives. Both households and government are aware of the occurrences and the proneness of their location to tidal flood inundation. They perceived that the main causes of tidal flood inundation origin both from natural and man-made behavior. Most households feel that their current condition is still safe. There is no intention to move to other places. The main identified reasons to stay in current location are self-owned building, access to work place, and relatively cheap daily expenditures in living. Tidal flood inundation has been regarding as usual event. Households in research location are dominated by low and medium risk indexes. The result is influenced by current adaptation strategies both conducted autonomously by affected households and planned by local governments. Different scenarios in tidal flood inundation depth provide different impacts in landuse, which are determined by their relative altitude to mean sea level. Muarareja is predicted as the first area to be affected by tidal flood inundation rise. The higher the scenarios of inundation depth, then the areas inundated are increasingly wider. Households mentioned that the prioritized adaptation strategies are rehabilitation of rivers and drainage channels, heightening and paving of streets, the mounting and heightening of river dykes, and establishment of water gates. Measures proposed by governments mainly structurally, such as the establishment retarding ponds equipped with hydro-pump and automatic tidal gate, arrangement of drainage system, street elevation in areas affected by tidal flood inundation, establishment of sea wall parallel with coast, establishment of river dykes, and mounting of rubber dams. Further adaptation strategies are suggested to incorporate households’ perception to tidal flood inundation. Households’ involvement and participation in various nonstructural measures in minimizing risk of tidal flood inundation are also highly suggested. GIS-raster environment tools have become useful tools in modeling impact of tidal flood inundation. Planned should be prioritized than autonomous adaptation strategy to prevent the growing maladaptive response in coastal area of Tegal Municipality.
Kata Kunci : genangan banjir rob, bahaya, kerentanan, penilaian resiko, persepsi, pendekatan partisipatif, strategi adaptasi, kapasitas penanggulangan, adaptasi masyarakat pesisir, kotamadya Tegal.
