Perancangan Pemanen Air Hujan Untuk Irigasi Hortikultura Di Greenhouse Sukamahi

Abstract

Kebutuhan air pada greenhouse terus meningkat seiring penggunaan air tanah yang masih dominan, sementara wilayah Bogor memiliki potensi curah hujan yang tinggi sehingga memungkinkan pemanfaatan air hujan sebagai sumber air alternatif. Penelitian dilaksanakan pada bulan Maret hingga Mei 2026 dengan lokasi penelitian pada Greenhouse Hidroponik 2 Bendungan Sukamahi. Penelitian bertujuan menganalisis kebutuhan air tanaman, potensi pemanenan air hujan, perancangan sistem pemanen air hujan, Rancangan Anggaran Biaya (RAB), serta efektivitas dan efisiensi penggunaan sistem. Penelitian dilakukan menggunakan analisis evapotranspirasi tanaman, curah hujan rencana, debit limpasan, serta perancangan dimensi sistem penyalur dan tangki penampung. Hasil penelitian menunjukkan bahwa kebutuhan air tanaman stroberi mencapai 101,75 m³/tahun dengan rata-rata 8,48 m³/bulan. Curah hujan andalan R80 diperoleh sebesar 83,05 mm dan menghasilkan potensi volume air hujan tertampung sebesar 10 m³ dengan luas atap 137,7 m² dan koefisien limpasan 0,9. Sistem dirancang menggunakan talang 4 inch dan pipa 2 inch dengan kapasitas tangki 10 m³ dengan efektivitas 85-100%. Total RAB sistem sebesar Rp54.249.909,00 termasuk PPN 12%. Sistem mampu menekan penggunaan listrik dan pompa hingga mendekati 100% dan menghemat biaya operasional sekitar 8%, meningkatkan kemandirian penyediaan air irigasi, serta mendukung konservasi sumber daya air melalui pengurangan penggunaan air tanah dan konsumsi energi.

Water demand in greenhouses continues to increase due to the predominant use of groundwater, while the Bogor region has high rainfall potential, allowing rainwater to be utilized as an alternative water source. This study was conducted from March to May 2026 at Hydroponic Greenhouse 2 of the Sukamahi Dam. The objectives of the study were to analyze crop water requirements, rainwater harvesting potential, rainwater harvesting system design, construction cost estimation, and the effectiveness and efficiency of the proposed system. The research employed crop evapotranspiration analysis, design rainfall analysis, runoff discharge analysis, and the design of conveyance systems and storage tanks. The results showed that the water requirement for strawberry plants reached 101.75 m³/year, with an average of 8.48 m³/month. The dependable rainfall (R80) was 83.05 mm, resulting in a potential harvested rainwater volume of 10 m³ from a roof area of 137.7 m² and a runoff coefficient of 0.9. The system was designed using 4 inch gutters, 2-inch pipes, and a storage tank capacity of 10 m³, achieving an effectiveness of 85–100%. The total estimated construction cost was IDR 54,249,909.00, including 12% VAT. The system can reduce electricity consumption and pump usage by nearly 100%, decrease operational costs by approximately 8%, enhance irrigation water self-sufficiency, and support water resource conservation through reduced groundwater extraction and energy consumption.