PEMANFAATAN SISTEM PEMANENAN AIR HUJAN (RAINWATER HARVESTING SYSTEM) DI PERUMAHAN BONE BIRU INDAH PERMAI KOTA WATAMPONE DALAM RANGKA PENERAPAN SISTEM DRAINASE BERKELANJUTAN - Ali, Ilham; Suhardjono, Suhardjono; Hendrawan, Andre Primantyo (Fakultas Teknik, Universitas Brawijaya, 2017)
ABSTRAK: Perumahan Bone Biru Indah Permai Kota Watampone terletak di Kabupaten Bone Propinsi Sulawesi Selatan. Permasalahan sumber daya air yang terjadi di perumahan ini, adalah; di musim hujan, luapan aliran drainase seringkali mengakibatkan terjadinya genangan pada jalan-jalan perumahan dan rumah-rumah penduduk, sementara di musim kemarau, terjadi kelangkaan air bersih. Penelitian ini mengkaji penerapan sistem drainase berkelanjutan dengan teknik pemanenan air hujan (PAH), dengan tujuan untuk mengetahui besaran potensi curah hujan yang dapat dipanen dan sisa limpasan yang harus di-manage oleh sistem drainase eksisting, serta untuk menentukan besaran kapasitas sarana PAH yang dibutuhkan dalam memenuhi keperluan suplai air bersih penduduk. Potensi air hujan dihitung dengan menggunakan tinggi hujan harian rata-rata bulanan yang diperoleh dari Metode Rata-rata Aritmetik. Kapasitas sarana PAH ditentukan dengan Metode Simulasi Tampungan Bulanan. Limpasan permukaan rencana dihitung dengan Metode Rasional. Dari hasil kajian diperoleh; potensi curah hujan yang dapat dipanen dari permukaan atap sebesar 147.009,86 m3 per tahun, sisa limpasan hujan yang bersumber dari atap sebesar 25.829,86 m3 per tahun dan total kapasitas tampungan sarana PAH yang dibutuhkan sebesar 4.743,20 m3. Dengan penerapan sistem PAH, mampu mereduksi jumlah limpasan drainase yang terjadi sekaligus juga dapat mengefektifkan fungsi saluran-saluran dan gorong-gorong drainase eksisting yang ada di perumahan ini. Kata kunci: sistem pemanenan air hujan, sistem drainase berkelanjutan. ABSTRACT: Bone Biru Indah Permai Residence City of Watampone lied in Bone Regency, Province of South Sulawesi. Problems of water resources that happened in this residence, were; in rainy seasons, overflow of drainage caused inundation on resindence's roads surfaces and inhabitants houses alwaysly, in the other side, in dry seasons, fresh water scarecity was occured. This research studying the implementation of sustainable drainage system by using rainwater harvesting system, with aims; to know how much potency of rainfall that can be harvested and remaining runoff must be managed by existing drainage system, and also to determine how big capacity of rainwater harvesting storage that needed to fulfill residence's inhabitant fresh water supply needs. Potency of rainwater was calculated by using monthly average rainfall height that obtained from height of monthly average daily-rainfall which was determined with Arithmatic Average Method. Capacity of the rainwwater harvesting storages was designed by using Monthly Storage Simulation Method. Design surface runoff was calculated by using Rational Method. Result of study showed that; there were 147.009,85 m3 in a year potency of rainwater that could be harvested from rooftop surfaces, 25.829,86 m3 rooftops-runoff which still remained in every year and 4.743,20 m3 the total of capacity of rainwater harvesting storage that needed. With the implementation of rainwater harvesting system, can reduce the total drainage run-off and in the same time can make the functions of the channels and culverts in this residence to be more efectively too.Keywords: rainwter harvesting system, sustainable drainage system