Jatiluhur Estate is an area located in Purwakarta Regency and was developed for residential, industrial, and commercial areas. Therefore, it is important to determine the availability of water that will meet water needs, and to evaluate the water reliability in future. This study aimed to model the river discharge in determination of water availability of Jatiluhur Estate. The methods used in this study include observational discharge data, evapotranspiration, rainfall, and area of flow. To analyze the availability of water, F.J. Mock method was used, where the F.J. Mock method can show water balance analysis for monthly discharge. The results showed that the availability of water with mainstay discharge Q80% and Q90% met the water needs of the Jatiluhur Estate or showed a surplus condition for 30 years (2020-2050).

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[ID] Permasalahan banjir merupakan permasalahan pengelolaan air yang sering terjadi di Indonesia. Untuk mengatasi permasalahan tersebut dibuat sebuah struktur yaitu waduk yang berfungsi sebagai pengendali banjir. Namun seiring waktu tampungan waduk akan semakin menurun akibat adanya akumulasi sedimen yang terbawa oleh air sungai yang masuk ke dalam waduk dan mengendap. Sehingga diperlukan evaluasi kinerja tampungan waduk tersebut, Permasalahan ini juga dialami oleh Waduk Selorejo yang terletak di Kabupaten Malang. Untuk melakukan evaluasi kinerja tampungan waduk digunakan bantuan perangkat lunak HEC-HMS yang dapat mensimulasikan debit banjir yang masuk beserta elevasi tampungan waduk. Berdasarkan hasil analisis tampungan Waduk Selorejo mampu untuk mengendalikan banjir periode ulang desain awal nya yaitu periode ulang 1000 tahun. Selain itu Waduk Selorejo juga mampu menampung debit banjir Probable Maximum Flood (PMF) apabila muka air awal waduk diturunkan sampai elevasi +605 m. [EN] Flood problem is a water management problem that often occurs in Indonesia. To overcome this problem, a structure is created, namely DAM that functions as a flood controller. However, over time the reservoir storage will decrease due to the accumulation of sediment carried by river water that enters the reservoir. So it is necessary to evaluate the performance of the Rervoir storage. This problem is also experienced by the Selorejo DAM which is located in Malang Regency. To evaluate the performance of the reservoir storage, the help of HEC-HMS software is used which can simulate the incoming flood discharge along with the elevation of the reservoir. Based on the analysis, the Selorejo DAM is able to control the flood of  its initial design period which is the 1000-year return period. In addition, the Selorejo Reservoir is also able to accommodate the Probable Maximum Flood (PMF) flood discharge if the initial water level of the reservoir is lowered to an elevation of +605 m.

Flood disaster management requires analysis and modeling, especially for the decision making of flood events. One way to analyze flood events is to use HEC-HMS software. HEC-HMS has three submodels: Loss, Transform, and Baseflow. In the flood discharge analysis, the selection of this sub-model is important because it is not certain that the method offered in this sub-model is suitable for all conditions, so it is necessary to choose which one is more suitable. Based on the results of the research, the SCS method can model well as evidenced by the good objective function values (RMSE (0.70 m; 49.05 m3 / s), Correl (0.931; 0.992), and DELTA PEAK (16.88%; 13.75%). The verification results are also show similar results (RMSE (0.63 m; 66,198 m3 / s), Correl (0.977; 0.916) and DELTAPEAK (43.04%; 32,754%). Therefore, it can conclude that the combination of benchmarking techniques that can be used for HEC-HMS modeling is the SCS curve number for losssubmodel, SCS unit hydrograph for transform submodel, and Recession constant for baseflowsubmodel.

Infrastructure Asset Management (IAM) is implemented to overcome problems in the management of the agricultural sector. For example, in this study, the 2 research areas had similar problems, namely the poor water supply system in which the amount of water supplied did not match the initial design. To overcome this problem, IAM implementation in these two areas focuses on Integrated Water Resource Management. The objective of this implementation is that the ratio between the amount of water distributed and the one designed is close to 1 or the same. Based on the research results shown after implementing this IAM this problem was resolved. However, Cu-Chi Irrigation Area is still experiencing problems in the financial sector because the income from the sale of water supply is still far from the initial supply price. Whereas in Papah Irrigation Area this financial problem can be resolved with the implementation of the Irrigation Service Fee (ISF) and better management of the management company. Seeing this result, this ISF system can be applied to DI Cu-Chi to overcome the imbalance problem between the costs incurred for water supply and the revenue from the sale of the water.