ANALISIS KAPASITAS SALURAN DI JARINGAN DRAINASE JALAN HARAPAN JAYA KOTA PONTIANAK

Abstrak

Penelitian ini mengevaluasi kemampuan jaringan drainase Jalan Harapan Jaya, Kecamatan Pontianak Selatan, Kota Pontianak dengan menganalisis kondisi lapangan, beban hidrologis, dan kapasitas hidraulik. Data primer meliputi kondisi fisik, dimensi penampang, kecepatan aliran, serta hasil observasi lapangan. Data sekunder mencakup curah hujan harian maksimum Stasiun PTK-11 Pontianak tahun 2007–2021 dan peta topografi. Analisis hidrologi meliputi pengujian distribusi probabilitas, uji kecocokan Chi-Kuadrat, distribusi Gumbel Tipe I, metode Mononobe, dan metode Rasional. Kapasitas saluran dievaluasi berdasarkan karakteristik geometrik dan persamaan Manning, kemudian dibandingkan dengan debit rencana periode ulang 10 tahun. Hasil analisis menunjukkan curah hujan rencana periode ulang 10 tahun sebesar 167,74 mm. Debit rencana sebesar 0,954 m³/detik pada Segmen A, 2,609 m³/detik pada Segmen B, dan 1,611 m³/detik pada Segmen C. Evaluasi lintasan menunjukkan beberapa bagian tidak mampu memenuhi debit rencana. Kapasitas lintasan terendah terdapat pada Segmen B kiri sebesar 0,02 m³/detik terhadap debit rencana 2,61 m³/detik. Survei juga menemukan sedimentasi, sampah, vegetasi, kerusakan, dan keterputusan jaringan. Alternatif dimensi hasil perhitungan mampu menghasilkan kapasitas di atas debit rencana pada seluruh bagian yang direncanakan. Peningkatan kapasitas perlu disertai pemulihan konektivitas, normalisasi, dan pemeliharaan berkala.

This study evaluates the capacity of the drainage network along Jalan Harapan Jaya, South Pontianak District, Pontianak City, by analyzing field conditions, hydrological loads, and hydraulic capacity. Primary data include physical conditions, cross-sectional dimensions, flow velocity, and field observation results. Secondary data comprise maximum daily rainfall recorded at the PTK-11 Pontianak Station from 2007–2021 and topographic maps. The hydrological analysis includes probability distribution testing, the Chi-Square goodness-of-fit test, the Gumbel Type I distribution, the Mononobe method, and the Rational method. Channel capacity was evaluated based on geometric characteristics and the Manning equation and then compared with the design discharge for a 10-year return period. The analysis results indicate that the design rainfall for the 10-year return period is 167.74 mm. The design discharge is 0.954 m³/s in Segment A, 2.609 m³/s in Segment B, and 1.611 m³/s in Segment C. The network evaluation indicates that several sections are unable to accommodate the design discharge. The lowest channel capacity is found in the left side of Segment B, with a capacity of 0.02 m³/s compared with the design discharge of 2.61 m³/s. The survey also identified sedimentation, waste accumulation, vegetation, damage, and network discontinuities. The alternative dimensions obtained from the calculations are capable of providing capacities exceeding the design discharge in all planned sections. Increasing channel capacity needs to be accompanied by restoring network connectivity, channel normalization, and regular maintenance.