A guerrilla gardener installed a pop-up wetland in the LA River. Here's how — and why

Artist Doug Rosenberg (center) leads a group of volunteers to his guerrilla wetland in the Los Angeles River.

Well-meaning city dwellers forgo permits and official procedure to rewild urban areas across the country. In downtown LA, artist Doug Rosenberg is trying to push the grassroots movement forward.

(Image credit: Courtney Theophin/NPR)