Android-Based Drainage Information System with Daily Precipitation Forecasts for Community Inundation Monitoring in Malang City

Abstract

Rapid urbanization in Malang City has reduced natural infiltration surfaces and intensified localized inundation, while drainage condition data has remained confined to agency archives and inaccessible to the public it most affects. This study reports the design, implementation, and evolution of Sistem Informasi Banyu Malang (SIBAMA), an Android application backed by a Laravel REST service and a MySQL spatial datastore, developed to disseminate drainage-network profiles and inundation information to citizens of Malang. The system integrates the Google Maps API to render survey-derived drainage polylines and inundation pins ingested from KML/KMZ and GeoJSON sources, and provides multi-temporal access across annual survey layers together with live CCTV at flood-prone points. The current release (v.6, 2025) extends the system from a static archive to a forecast-coupled tool: a daily synchronization with the Open-Meteo API retrieves the 24-hour precipitation sum (R24) and maximum precipitation probability, and the current-day R24 drives a derived runoff status that recolors each channel segment as normal or inundation-prone and animates the cross-section overflow illustration. The release also integrates the municipal SAMBAT complaint channel, extends drainage coverage to all five districts, and is implemented in Kotlin. Functional verification used black-box testing with equivalence partitioning, complemented by a user acceptance testing instrument. The work contributes a replicable, low-infrastructure architecture that couples a multi-temporal survey record with public weather-forecast data for participatory municipal inundation monitoring.