THE EFFECT OF LAND USE CHANGES TO DISCHARGE EXTRIMITIES IN CIMAHI WATERSHED – UPPER CITARUM WATERSHED, WEST JAVA

• Main Author: Ai Nurhayati, Siti
• Format: Theses
• Language: Indonesia
• Subjects: Teknik saniter dan perkotaan; teknik perlindungan lingkungan
• Online Access: https://digilib.itb.ac.id/gdl/view/43319
• Institution: Institut Teknologi Bandung

The development of cities and regencies in the Cimahi watershed area increases the rate of population growth resulting in high land requirements in the Cimahi watershed area. Transfer of land functions affect the flow of runoff and discharge of the Cimahi River. Increasing runoff will cause flooding during the rainy season. In the dry season, the base flow in the river will be reduced due to lack of infiltration into the soil or commonly called the phenomenon of extreme discharge. This research was conducted with the aim to assess the hydrological function of the area in the Cimahi watershed which is the impact of land use change and to analyze the effect of land use change in the Cimahi watershed on the extremity of water resources in terms of both quantity and quality. The conservation index is a parameter used in the assessment of the region's hydrological function. The conservation index consists of the natural conservation index and the actual conservation index (IKA and IKC) which are calculated based on rainfall, rock type, slope, height and land use. A small conservation index indicates a high value of runoff coefficient (C). The results of the conservation index show that there was a decrease in the value of the IKC from 0.637 in 2000 to 0.608 in 2012. The debit extremities can be seen based on calculations by moving averages on the discharge data, and the resulting maximum discharge value is greater and the value of the base flow (baseflow) is getting smaller. Land changes in the Cimahi watershed also have an influence on river water quality. This is indicated by the negative correlation between DO values and the growth of settlements in the watershed area.