ANALISA OPERASI PINTU PENGENDALI BANJIR SUNGAI CIMANUK LAMA RAMBATAN INDRAMAYU - Ibrohim, Sahid (2016)
Pintu pengendali banjir menjadi penghubung antara Sungai Cimanuk Induk dengan Cimanuk Lama. Lokasi penelitian pintu pengendali banjir di Bangkir, Indramayu. Pintu pengendali banjir beroperasi sesuai fungsi yaitu untuk mencegah akan terjadinya banjir dan memenuhi kebutuhan air. Pasokan kebutuhan air pada pintu pengendali banjir ini diantaranya untuk memenuhi kebutuhan air irigasi, kebutuhan air PDAM, dan pemeliharaan sungai. Meningkatnya jumlah penduduk dan berkurangnya jumlah area sawah mengakibatkan terjadinya perubahan dalam memenuhi debit kebutuhan air. Penelitian ini bertujuan untuk mengetahui debit yang dialirkan melalui pintu pengendali. Untuk mengetahui prakiraan debit banjir dilakukan analisis hidrologi berupa analisis frekuensi dari data AWLR Pos Kertasemaya Sungai Cimanuk. Alternatif operasi pintu dilakukan berdasarkan beberapa keadaan yaitu keadaan Q2, Q20, Q50, dan Q100. Hasil penelitian menunjukkan bahwa debit maksimal dalam memenuhi kebutuhan air yaitu 7,324 m3/det. Besaran debit tersebut menjadi batas minimum dalam mengalirkan air ke Sungai Cimanuk Lama. Sedangkan batas maksimum debit berdasarkan perhitungan bankfull capacity di hilir pintu yaitu berada di ketinggian 2 m atau sebesar 48,597 m3/det. Debit puncak banjir Q100 pada hulu pintu sebesar 1153,8 m3/det, sedangkan untuk Q2 sebesar 489,216 m3/det. Berdasarkan hasil penelitian, beberapa alternatif operasi pintu dapat memenuhi batas minimum dan maksimum debit pengambilan.;--- Flood control intake as a connection between Cimanuk main river and Cimanuk old river. Flood control intake for this research is located at Bangkir, Indramayu. Flood control intake is operating according to its function which is to prevent flooding and to fulfill the water requirement. The water supply in this flood control intake are to fulfill the irrigation water requirement, PDAM water requirement, and river maintenance. The increasing number of people and the reduction the area of rice fields caused a change in fulfill water requirement discharge. The purpose of this research is to know the conducted discharge through the controlling intake. The using hidrology analysis to know the flood discharge prediction is frequency analysis from AWLR data of Kertasemaya Post in Cimanuk river. The alternative of the intake operation are based on flood condition Q2, Q20, Q50, and Q100. The result of the analysis show that maximum discharge for fulfill the water requirement is 7,324 m3/s. The discharge values is being the minimum limit to conducted water to Cimanuk Old River. In the other hand, the discharge maximum limit based on bankfull capacity calculation in intake lower course is in 2 m or 48,597 m3/s. maximum flood discharge Q100 in upper intake is 1153,8 m3/s, and for Q2 is 489,216 m3/s. Based on The result of the analysis, some alternatives intake operation can fulfill the intake discharge in minimum and maximum limit.