U.S. Environmental Protection Agency Administrator Michael Regan got a first-hand look Friday at the Tijuana River Valley, where hundreds of millions of gallons of water laced with raw sewage, trash and industrial chemicals regularly foul San Diego shorelines, shuttering beaches as far north as Coronado.

“You know, you can read about these things and have your own visualization, but seeing it first-hand really is impactful,” said Regan, the first EPA administrator to tour the local border region.