COMPARATIVE STUDY ON RAINFALL-RUNOFF HYDROLOGIC MODEL NAM, SACRAMENTO, HBV’96 AND NRECA FOR GENERATING INFLOW DATA INPUT ON WATER ALLOCATION ANALYSIS AT CIUJUNG WATERSHED USING WATER EVALUATION AND PLANNING SYSTEM (WEAP) SOFTWARE

• Main Author: SETYA WARDHANA (NIM : 95015001), MOHAMMAD
• Format: Theses
• Language: Indonesia
• Online Access: https://digilib.itb.ac.id/gdl/view/29017
• Institution: Institut Teknologi Bandung

The NAM, Sacramento, HBV'96 and NRECA models are rainfall-runoff model that create hydrological function based on simplified algorithm from cognition of hydrologic events. The modeling on these study was conducted on a bi-weekly basis in the Ciujung Watershed on 1998-2009 to be validated in 2013-2015. The hydrological modeling is conducted with the aim to find out the feasibility of the implementation of rainfall-runoff model which is able to give the best result in approaching the observation discharge value in Pamarayans AWLR to then be used as the basis of water availability data to determining the general overview of water allocation in Ciujung Watershed. Based on the results of model comparative analysis through qualitative assessment criteria (flow hydrograph, flow duration curve and scatter plot), quantitative (probability suitability 50%, 75%, 80%, 90% and 95%), and statistics (Bias, Relative <br /> <br /> Bias, R Squared, R2 SQRT, Nash-Sutcliffe and Relative Volume Error), NRECA Model indicated as the better for rainfall-runoff modelling in Ciujung Watershed than NAM <br /> <br /> whose cant formed the low flow pattern and tend to decrease, Sacramento that the low flow fluctuations less suited and HBV96 that had lag in modelling results. Based on that, NRECA used for the basic analysis of water availability in Ciujung Watershed model with values of parameter Nominal = 117.961; Ra = 89.807; PSUB / P1 = 0.600 and GWF / P2 = 0.500 and initial values SM Storage = 300 mm; GW Storage = 75 mm and Plant Factor = 0.400. <br /> <br /> Considering water requirements in Ciujung watershed which are classified for utilization of drinking water through 11 nodes of 450 liters/sec with constant use, 12 industry nodes of 2,090 liters / sec with also constant use and Ciujung Irrigation Area of 21,350 ha whose the water demand were fluctuative, it is known with Q80 that the Ciujung Watershed water balance is deficit for four and a half months while on average of 1997-2015 is deficit for eight months. With the existence of the Karian Reservoir, the amount of deficit and the number of occurences can be reduced, that is in Q80 to only one and a half months and the average of 1997-2015 to four months.