The Rio Hondo watershed (HUC 13060008) is located in southern California and covers an area of approximately 227 square miles. The watershed is characterized by a Mediterranean climate with hot, dry summers and mild, wet winters. The watershed is also subject to periodic droughts and flash floods. Hydrologically, the Rio Hondo watershed is marked by steep terrain and a high degree of urbanization. This has led to significant modifications of the natural hydrology, including channelization of the river and construction of numerous flood control structures. Snowpack in the Rio Hondo watershed is typically low due to the region's Mediterranean climate. Surface water in the watershed is primarily supplied by the Rio Hondo river and its tributaries, which flow into the San Gabriel River and ultimately the Pacific Ocean. Reservoirs within the Rio Hondo watershed include the Santa Fe Dam and Whittier Narrows Dam. These reservoirs are primarily used for flood control and recreation. In recent years, the Rio Hondo watershed has experienced a trend of decreasing precipitation and increasing temperatures, which has contributed to worsening drought conditions. Additionally, the region is highly vulnerable to the effects of climate change, including increased frequency and severity of extreme weather events.