The Los Angeles River is a major river in Los Angeles County, California. It flows nearly 51 miles from Canoga Park through the Sen Fernando Valley, Downtown Los Angeles, and the Gateway Cities to its mouth in Long Beach. Urban development and periodic droughts have increased the need for water conservation and groundwater recharge. Climate change has further elevated current drought conditions in California bringing record high temperatures (2014) and the lowest annual rainfall on record (2013). California’s snowpack hit an all-time low in 2015 creating a significant water deficit and unexpected longer-term recovery times. It is imperative to preserve what local water resources remain, protect native habitat, and restore watersheds.

The Council For Watershed Health is leading efforts to target the eradication of Arundo donax, a highly non-native invasive and high-water use riparian plant, within the Upper Los Angeles River Watershed. Arundo (commonly referred to as giant reed) has significant negative impacts on water availability, water quality (i.e. sediment loads, temperature, pathogens, nutrient loading, flow modification), habitat, fires, and infrastructure. Arundo transpires water at a rate that is 5x higher than native vegetation. Invasive Arundo populations that negatively impact local water resources have been identified, both in the City of Los Angeles and upstream in the surrounding San Gabriel, Santa Susana, and Santa Monica Mountains.

The eradication of Arundo and re-establishment of native plants will improve water availability and water quality downstream.