This episode is on site where a beautiful desert mountain river flows through an estuary and into the Pacific Ocean. Before the Tijuana River meets the ocean, it navigates through a dense urban border region with 5 million people. The outcome is a river that is carrying toxic sewage and pollution to the ocean, closing beaches and creating illness in the river and beach communities. This is the first episode in a series about this beautiful place, the epic pollution, and the incredible people who are engaged in the work to clean up this river and ocean.