When Extreme Rainfall Meets an Unrecovered Watershed: The Anatomy of the Padang Flood

The massive flood that hit Padang City on 3 August 2026 was not simply a matter of extreme rainfall. It was a stark demonstration of how a landscape’s ability to absorb, store, and channel water determines the severity of a disaster. On that day, heavy rain with very extreme intensity fell almost all day, causing four main rivers—Batang Kuranji, Batang Arau, Batang Aie Dingin, and Batang Guo—to overflow simultaneously and inundate at least 15 points across the city. While the rainfall was exceptionally high, the disaster was amplified by the condition of the upstream watersheds, which had not yet recovered from a previous catastrophe. Satellite imagery from the Sentinel-2 satellite, captured on 31 July 2026, just three days before the flood, shows that the upper Batang Kuranji watershed was still bearing the scars of a devastating flash flood that occurred on 26–27 November 2025. A comparative analysis of images from 4 October 2025 and 1 February 2026 reveals that approximately 80 hectares of vegetated area had been transformed into bare soil or sediment deposits. Furthermore, the river corridor had expanded dramatically from 37 hectares to 153 hectares. This evidence indicates that the watershed’s natural capacity to retain and slowly release rainwater was severely compromised. When the extreme rainfall occurred, the degraded landscape failed to act as a sponge. Instead of being absorbed, the water quickly turned into surface runoff, rushing into the tributaries and overloading the main rivers in a very short time. The result was a simultaneous overflow of multiple rivers, a classic symptom of a watershed that has lost its hydrological function. The Padang flood is a clear lesson that urban flooding cannot be separated from the health of upstream watersheds, and that recovery from one disaster is critical to mitigating the next.