Lopez Dam, also known as Lopez Reservoir, is a federal-owned structure located in Los Angeles, California. Completed in 1954, the dam's primary purpose is debris control, with the additional benefit of flood risk reduction. Standing at a height of 50 feet with a hydraulic height of 44 feet, the dam has a storage capacity of 209 acre-feet and a maximum discharge of 32,000 cubic feet per second. It spans 1,300 feet across the Pacoima Wash, serving as a vital component of water resource management in the region.

Despite being classified as high risk in a 2009 assessment by the US Army Corps of Engineers (USACE), efforts are in place to mitigate potential hazards associated with the dam. USACE actively engages with state and local emergency managers, conducts emergency exercises, and closely monitors rainfall forecasts to provide timely flood warnings. Continuous inspections, monitoring, maintenance, and repair work are conducted to ensure the dam's structural integrity and performance. Risk communication activities, including updates to the Emergency Action Plan and coordination with first responders, are also ongoing. Further studies of the dam are planned for 2023 to enhance its safety and resilience for the surrounding urbanized and densely populated areas of Los Angeles and San Fernando, California.