No abstract

Saguling reservoir is one of the three largest reservoirs in the Citarum River Basin. The water source of its reservoir originates from Upper Citarum river basin, with gauging station located in Citarum-Nanjung and local discharge from tributaries around the reservoir. The problem is there is no observation of local discharge from the tributaries, thus its potential is estimated. The purpose of this study is to analyze the potential of local discharge with the Hydrology Engineering Center-Hydrologic Modeling System (HEC-HMS) model. The HEC-HMS Rainfall-runoff method is used for calculating the potential of the local discharge that flows into Saguling resevrvoir. The parameters used in the model are deficit constant (loss parameter), linear reservoir (baseflow parameter), dan lag time (transform parameter). Rainfall-runoff model produced good calibration values for Citarum-Nanjung Gauging Station with R2 of 0.8 and the Nash-Sutcliffe efficiency (NSE) value of 0.788. The verification result carried out in Saguling reservoir gives NSE of 0.8343 and R2 value of 0.83. The simulation shows that the potential discharge from local river contributes about 21.64% of the total discharge that enters  into the reservoir with monthly dependable flow for power plants, Q80 and Q85 values at 8,23 m3/s and 5,69 m3/s, respectively. The average discharge of local rivers can generate electricity of 3.89 MW - 162 MW.Keywords: Local discharge, rainfall runoff, potential discharge, Saguling reservoir

Planning and management of water resources are dependent on the quality of hydrological data. Hydrological data plays an important role in hydrological analysis. The availability of good and qualified hydrological data is one of the determinants of the results of hydrological analysis. However, the facts indicate that many of the available data do not fit their ideal state. To solve this problem, a hydrological data quality control model should be established in order to improve the quality of national hydrological data. The scope includes quality control of rainfall and discharge data. Analysis of the quality control of rainfall data was conducted on 58 rainfall stations spread on the island of Java. The analysis shows that 41 stations are good categorized, 14 stations are in moderate category and 3 stations are badly categorized. Based on these results, a light improvement scenario was performed, good category Station increased to 46 stations, moderate category decreased to 11 stations and bad category reduced to 1 Stations. Quality control of discharge data analysis was conducted on 14 discharge stations spread on Java Island. Analyzes were performed for QC1, QC2 and QC3 then got final QC value. The results on the final QC show no stations for good category, 2 stations for moderate categories and 12 stations for bad category. Based on the results of the analysis, a light improvement scenario was performed with the result of bad category increased to good category 5 stations, bad category increased to moderate 7 stations, and moderate category 1 stations.

Perencanaan dan pengelolaan sumber daya air sangat bergantung pada kualitas data hidrologi yang digunakan. Data hidrologi memainkan peranan penting dalam analisis hidrologi. Ketersediaan data hidrologi yang baik dan berkualitas merupakan salah satu faktor penentu hasil analisis hidrologi. Akan tetapi, fakta di lapangan menunjukkan bahwa banyak data yang ada tidak sesuai dengan kondisi idealnya. Guna mengatasi masalah tersebut, perlu dibentuk model kendali mutu data hidrologi dalam rangka meningkatkan kualitas data hidrologi secara nasional. Lingkup kendali mutu yang dilakukan meliputi kendali mutu data hujan dan kendali mutu data debit. Analisis kendali mutu data hujan dilakukan terhadap 58 pos hujan yang tersebar di pulau Jawa.  Hasil analisis menunjukkan bahwa 41 pos berkategori baik, 14 pos berkategori sedang dan 3 pos berkategori buruk. Berdasarkan hasil tersebut dilakukan skenario perbaikan ringan, pos kategori baik meningkat menjadi 46 pos, kategori sedang berkurang menjadi 11 pos dan kategori buruk berkurang menjadi 1 pos. Analisis kendali mutu data debit dilakukan terhadap 14 pos duga air yang tersebar di pulau Jawa. Analisis dilakukan untuk QC1, QC2 dan QC3 kemudian didapat nilai QC akhir. Hasil pada QC akhir menunjukan tidak ada pos untuk kategori baik, 2 pos kategori sedang dan 12 pos kategori buruk. Berdasarkan hasil analisis tersebut dilakukan skenario perbaikan ringan dengan hasil kategori buruk meningkat menjadi baik 5 pos, kategori buruk meningkat menjadi sedang 7 pos, dan kategori sedang 1 pos.