UPPER CITARUM WATERSHED BASEFLOW ANALYSIS USING ECKHARDT RECURSIVE DIGITAL FILTER

• Main Author: NURROHMAN , FAJAR
• Format: Final Project
• Language: Indonesia
• Online Access: https://digilib.itb.ac.id/gdl/view/27115
• Institution: Institut Teknologi Bandung

Baseflow is a component of river flow originating from groundwater discharges and contributes significantly to river flow especially when precipitation is low. The amount of baseflow should be estimated to know the capacity of the Upper Citarum watershed in fulfilling the hydrological functions. The separation of baseflow in this study was conducted by recursive digital filter method developed by Dr. K. Eckhradt. The data used in the form of daily river discharge period 1918-1935 and 1976-2015 originated from Nanjung Hydrometric Station located downstream of Upper Citarum watershed. The annual baseflow value of the Upper Citarum watershed in the 1918/19-1934/35 period ranged from 32.53 m3/sec to 64.84 m3/sec, and in the period 1976/77-2014/15 had a range of 29.52 m3/sec to 129.86 m3/sec. Spearman-Conley (? = 5%) test of annual baseflow value showed no significant correlation or trend in both periods. The Kolmogorov-Smirnov test (? = 5%) shows the daily distribution of different daily baseflow between the two periods. The baseflow variability of Upper Citarum Watershed is inseparable from the influence of climate variability and changes in cover and land use. Each of these factors has an influence; With Indonesia flanked by the Indian Ocean and the Pacific Ocean, and with the rapid development in the Upper Citarum Watershed. The potential decrease in the baseflow contribution of the Upper Citarum Watershed can have implications for drought in the dry season and affect the well-being of the people dependent on the river. Consequently, sustainable and sustainable management of water resources and watershed conservation is needed as a solution to the baseflow decline so that the quality, quantity and continuity of water resources can be maintained.