ANALYSIS OF METEOROLOGICAL FACTORS IN THE GROUNDWATER RECHARGE ZONE (CASE STUDY: CIANJUR DISTRICT)

• Main Author: Pasa Kencana, Amanda
• Format: Final Project
• Language: Indonesia
• Subjects: Geologi, hidrologi & meteorologi
• Online Access: https://digilib.itb.ac.id/gdl/view/75603
• Institution: Institut Teknologi Bandung

Households in Cianjur Regency (86.62 percent) use groundwater as a source of drinking water, bathing, washing, toilet, and garden irrigation. The selling price of clean water, in this case groundwater, is increasing every year, so it is important to study the distribution of groundwater through the distribution of recharge zone conditions and the estimated discharge. The determination of the groundwater recharge zone is obtained by applying geospatial analysis using the scoring method from the parameters of rock permeability, rainfall, soil type, and slope. After obtaining the groundwater recharge zone, evapotranspiration, and water balance calculations are carried out to obtain an estimate of groundwater discharge. In this study, climate classification was also carried out, determination of monsoon onset and calculation of the return period of rainfall to determine the distribution of rainfall in Cianjur Regency. Based on the scoring method, the area of the groundwater recharge zone in Cianjur Regency is 137.07 km2 and the groundwater release zone is 1669.62 km2. Rainfall that falls on the recharge zone is highly dependent on the beginning of the rainy season, in this case it occurs in the second cycle dasarian of November at three points of the recharge zone (Sukaresmi, Bojong Picung, and Pagelaran sub-districts), while the onset of the monsoon is detected in the first and second cycle dasarian of September or a one month delay before the rainy season occurs because this region requires heat capacity due to the sea and tropical forests. From the recapitulation of rainfall in Cianjur Regency using the Oldeman method, this region is divided into three agroclimatic zones, namely B1, C1, and C2. Meanwhile, the maximum rainfall distribution mapping occurs in the coastal zone. This can be caused by the high evaporation that occurs on the coast from sea water, as well as the difference in air temperature between the land and the ocean causing air lifting (thermal convergence) around the coast. While in the northwestern part of the study area there is Mount Gede which makes the air lift orographically, thus making high infiltration values that affect the acquisition of groundwater content values.