Smuggler's Gulch sits at the westernmost edge of the San Diego Tijuana border.
It was a main thoroughfare for illegal crossings. But traffic has dwindled during the last decade. The majority of migrants try their luck further east.
Nevertheless, in 2005, Congress allowed the Secretary of Homeland Security to waive any laws that stood in the way of filling in Smuggler's Gulch to build a taller, stronger border fence, and to pave over parts of the canyon for roads.
Josh Gough, who's a Border Patrol supervisor, says it used to take five agents to patrol Smuggler's Gulch. He says now, "If you could cut an agent in half, you can patrol this area with one-point-five."
Environmentalists say even though the new fence may make Border Patrol agents' work less taxing, the project is environmentally costly. They say sediment from the project could further damage the estuary below.
