The Los Angeles River.
What is a Watershed?
Where does pollution go when it rains in Los Angeles?
Learn about how stormwater flows through the Los Angeles River watershed from our recent summer intern, Jake Tanda. Jake is a senior at USC and was one of USC Wrigley Institute’s 2026 Summer Environmental Communications Interns. He was co-mentored by USC Sea Grant’s Dr. Amalia Almada and Sydney Rilum, and worked on promoting healthy watersheds through public education.
Across much of the highly urbanized city of Los Angeles, rainwater flows over streets and into storm drains and waterways, including the LA River, before eventually reaching the Pacific Ocean. Along the way, it can pick up litter, oil, bacteria, and other pollutants.
The good news? We can all help protect our shared watershed by reducing waste, properly disposing of pollutants, and keeping our streets and waterways clean. Small actions upstream can make a big difference downstream.
Watch his video “What is a watershed?” below to learn more.