Author(s): Budi Indra Setiawan; Dendin Hermawan; Yuyun Permana; Muhammad Nashir; Rihadi Achsani Takwim; Mufthi Azis
Linked Author(s): Budi Indra Setiawan
Keywords: Cidanau watershed Climate Change Seasonal Variation Discharge Fluctuation
Abstract: Cidanau watershed in Serang Regency is a small watershed of ±22.4 thousand ha, but it is an important water source, especially for the industrial area in Cilegon City. Raw water from the Cidanau River is tapped and piped ±27 km to a water treatment plant by PT Krakatau Tirta Industri (KTI) for consumer distribution. KTI has a capacity of more than 2 m3/s and has achieved a daily production of 1.7 m3/s of clean water. As the demand for clean water continues to grow, KTI seeks to increase its production capacity to 3.5 m3/s by 2025. This study aims to provide an overview of the extent to which climate change and shifts in the rainy season have occurred and their effects on the discharge and water volume of the Cidanau River. Quantitative analysis was performed using climate data for 46 years (1978-2023) and discharge data for 28 years (1996-2023) using linear models, the Mann-Kendall test, and water balance analysis. In conclusion, the watershed has been affected by climate change, characterized by an increase in temperature and a significant shift in seasons, but with negligible effect on water discharge. Since the maximum runoff is exceptionally large during the rainy season, water conservation in the form of water storage is particularly important to anticipate its decrease during the dry season. Water conservation through tree planting is a potential option to reduce surface runoff and increase water infiltration into the soil layers.
Year: 2025