Perencanaan Sumur Resapan dan Kolam Retensi di Bogor Barat Agrohills Kabupaten Bogor

Abstract

Bogor Barat Agrohills adalah proyek kaveling berkonsep eduwisata di Kecamatan Leuwisadeng Kabupaten Bogor. Saat ini pemerintah berupaya untuk menyimpan air sebanyak mungkin ke dalam tanah dan berusaha untuk mencapai zero runoff. Sejalan dengan itu maka penelitian bertujuan merencanakan sumur resapan dan kolam retensi di Bogor Barat Agrohills. Dari hasil analisis diperoleh nilai permeabilitas tanah di lokasi tidak memenuhi syarat SNI 03-2453-2002 sehingga direncanakan hanya pembuatan kolam retensi. Dari analisis curah hujan dengan metode Gumbel, diperoleh curah hujan rencana sebesar 147,9 mm untuk periode ulang 5 tahun. Dari hasil pengamatan diperoleh 4 daerah tangkapan air (DTA) dan nilai koefisien limpasan gabungan sebesar 0,32. Kolam retensi direncanakan memiliki 3 tipe dan berjumlah satu buah di tiap DTA. Tipe 1 memiliki panjang 10,0 m dan lebar 6,7 m. Tipe 2 memiliki panjang 8,6 m dan lebar 5,8 m. Tipe 3 memiliki panjang 6,4 m dan lebar 4,3 m. Ketiga tipe kolam memilki kedalaman 4 m. Lokasi kolam retensi direncanakan di dekat outlet setiap DTA. Kolam tipe 1 berjumlah dua buah sedangkan kolam tipe 2 dan tipe 3 masing - masing satu buah. Biaya pembuatan kolam retensi tipe 1 (2 buah kolam) sebesar Rp159.620.000,00, tipe 2 sebesar Rp68.310.000,00, dan tipe 3 sebesar Rp52.150.000,00.

Bogor Barat Agrohills is a land plot project with an edutourism concept in Leuwisadeng District, Bogor Regency. Currently the government is trying to store as much water as possible into the ground and to achieve zero runoff. Accordingly, this study aims to plan infiltration wells and retention ponds in Bogor Barat Agrohills. From the results of the analysis, the permeability value of the soil at the location does not meet the SNI 03-2453-2002 requirements, so only retention ponds were planned. From the rainfall analysis using the Gumbel method, a design rainfall was 147.9 mm for the 5-year return period. From the observations were obtained 4 water catchment areas and a combined runoff coefficient value of 0,32. Three types of retention ponds were planned and one pond in each catchment area. Type 1 had dimention of 10,0 m long and 6,7 m wide and type 2 had 8,6 m long and 5,8 m wide, while type 3 had 6,4 m long and 4,3 m wide. The three types of ponds had a depth of 4 m. The location of the retention ponds were planned near the outlet of each DTA. There were two ponds of type 1 pond and one each of type 2 and type 3 ponds. The construstion cost of retention pond type 1 (2 ponds) was IDR159.620.000.00, type 2 was ID68.310.000.00, and type 3 was IDR52.150.000.00.