Analisis kerapatan jaringan stasiun hujan di DAS Gandong, Jawa Timur

Abstract

Rainfall is a key component in hydrological analysis and plays a critical role in the planning and management of water resources, where the quality and representativeness of data are strongly influenced by the number, density, and spatial distribution of rainfall stations. This study aims to determine the optimal number and spatial distribution pattern of rainfall stations in the Gandong Watershed, Magetan Regency, East Java, in order to ensure that the collected rainfall data accurately reflect actual field conditions.The methods employed include analysis based on the standards of the World Meteorological Organization (WMO) and the Kagan-Rodda method, utilizing watershed maps and historical rainfall data, both daily and monthly.The results show that, according to WMO standards, the minimum requirement is one station with a density of 162.797 km² per station. In contrast, the Kagan-Rodda method provides more detailed results, indicating that for daily data with 10% and 5% error tolerances, station densities of 81.398 km²/station and 20.349 km²/station are required, respectively. For monthly data, the required densities for 10% and 5% errors are 162.797 km²/station and 40.698 km²/station, respectively. In general, the existing rainfall station network in the Gandong Watershed is considered adequate; however, optimizing the number and spatial distribution of stations remains necessary to improve the accuracy of hydrological analysis.