Desain Tata Letak dan Dimensi Jaringan Perpipaan Submain dan Manifold Irigasi Tetes

Abstract

Kendala utama penerapan irigasi tetes di kawasan Food Estate Humbang Hasundutan adalah kondisi topografi yang bergelombang. Tujuan penelitian ini untuk menganalisis kebutuhan air irigasi, mendesain layout dan dimensi jaringan perpipaan sub-unit irigasi tetes, mendesain layout dan dimensi jaringan perpipaan submain, menghitung panjang pipa manifold dan pipa submain, serta menghitung biaya bahan jaringan perpipaan. Nilai satuan kebutuhan air (SKA) irigasi sebesar 3.79 mm/hari atau setara dengan 0.14 l/det/ha – 0.29 l/det/ha. Desain layout pipa manifold dibuat memotong arah kontur sedangkan pipa lateral searah kontur dengan pipa yang digunakan adalah jenis pipa PVC diameter 2 inci untuk pipa manifold dan pipa LDPE 1/2 inci untuk pipa lateral. Pipa submain digunakan jenis pipa HDPE diameter 2 inci dengan prinsip satu sub-unit dihubungkan dengan satu submain dari riser/outlet tertentu. Total kebutuhan pipa manifold di lima petak lahan sepanjang 637 meter, sedangkan pipa submain sepanjang 989 meter. Biaya bahan jaringan perpipaan irigasi tetes “dengan” water meter sebesar Rp. 46.206.065,-/ha dan “tanpa” water meter sebesar Rp.35.865.929,-/ha.

The main obstacle to the application of drip irrigation in the Humbang Hasundutan Food Estate area is the undulating topography. The purpose of this study was to analyze irrigation water requirements, design of layout and dimensions of drip irrigation sub-unit piping network, design of layout and dimensions of sub-main piping network, calculate length of manifold pipe and sub-main pipe, and calculate piping network material costs. The unit value of irrigation water demand (SKA) is 3.79 mm/day or equivalent to 0.14 l/sec/ha – 0.29 l/sec/ha. The layout design of the manifold pipe is made to cut the contour direction while the lateral pipe is in the direction of the contour with the pipe used is a 2 inch diameter PVC pipe for the manifold pipe and 1/2 inch LDPE pipe for the lateral pipe. The submain pipe is a 2 inch diameter HDPE pipe with the principle of one sub-unit connected to one submain from a particular riser/outlet. The total demand for manifold pipes in five plots of land is 637 meters long, while the submain pipe is 989 meters long. The cost of drip irrigation piping network materials "with" a water meter is Rp. 46,206,065,- /ha and “without” water meter is Rp.35,865,929,-/ha.